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* ARM: ep93xx: remove MaverickCrunch supportArnd Bergmann2021-08-0425-557/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The MaverickCrunch support for ep93xx never made it into glibc and was removed from gcc in its 4.8 release in 2012. It is now one of the last parts of arch/arm/ that fails to build with the clang integrated assembler, which is unlikely to ever want to support it. The two alternatives are to force the use of binutils/gas when building the crunch support, or to remove it entirely. According to Hartley Sweeten: "Martin Guy did a lot of work trying to get the maverick crunch working but I was never able to successfully use it for anything. It "kind" of works but depending on the EP93xx silicon revision there are still a number of hardware bugs that either give imprecise or garbage results. I have no problem with removing the kernel support for the maverick crunch." Unless someone else comes up with a good reason to keep it around, remove it now. This touches mostly the ep93xx platform, but removes a bit of code from ARM common ptrace and signal frame handling as well. If there are remaining users of MaverickCrunch, they can use LTS kernels for at least another five years before kernel support ends. Link: https://lore.kernel.org/linux-arm-kernel/20210802141245.1146772-1-arnd@kernel.org/ Link: https://lore.kernel.org/linux-arm-kernel/20210226164345.3889993-1-arnd@kernel.org/ Link: https://github.com/ClangBuiltLinux/linux/issues/1272 Link: https://gcc.gnu.org/legacy-ml/gcc/2008-03/msg01063.html Cc: "Martin Guy" <martinwguy@martinwguy@gmail.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
* Linux 5.14-rc4v5.14-rc4Linus Torvalds2021-08-021-1/+1
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* Merge tag 'perf-tools-fixes-for-v5.14-2021-08-01' of ↵Linus Torvalds2021-08-013-13/+42
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux Pull perf tools fixes from Arnaldo Carvalho de Melo: - Revert "perf map: Fix dso->nsinfo refcounting", this makes 'perf top' abort, uncovering a design flaw on how namespace information is kept. The fix for that is more than we can do right now, leave it for the next merge window. - Split --dump-raw-trace by AUX records for ARM's CoreSight, fixing up the decoding of some records. - Fix PMU alias matching. Thanks to James Clark and John Garry for these fixes. * tag 'perf-tools-fixes-for-v5.14-2021-08-01' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux: Revert "perf map: Fix dso->nsinfo refcounting" perf pmu: Fix alias matching perf cs-etm: Split --dump-raw-trace by AUX records
| * Revert "perf map: Fix dso->nsinfo refcounting"Arnaldo Carvalho de Melo2021-07-301-2/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This makes 'perf top' abort in some cases, and the right fix will involve surgery that is too much to do at this stage, so revert for now and fix it in the next merge window. This reverts commit 2d6b74baa7147251c30a46c4996e8cc224aa2dc5. Cc: Riccardo Mancini <rickyman7@gmail.com> Cc: Ian Rogers <irogers@google.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Krister Johansen <kjlx@templeofstupid.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| * perf pmu: Fix alias matchingJohn Garry2021-07-271-9/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit c47a5599eda324ba ("perf tools: Fix pattern matching for same substring in different PMU type"), may have fixed some alias matching, but has broken some others. Firstly it cannot handle the simple scenario of PMU name in form pmu_name{digits} - it can only handle pmu_name_{digits}. Secondly it cannot handle more complex matching in the case where we have multiple tokens. In this scenario, the code failed to realise that we may examine multiple substrings in the PMU name. Fix in two ways: - Change perf_pmu__valid_suffix() to accept a PMU name without '_' in the suffix - Only pay attention to perf_pmu__valid_suffix() for the final token Also add const qualifiers as necessary to avoid casting. Fixes: c47a5599eda324ba ("perf tools: Fix pattern matching for same substring in different PMU type") Signed-off-by: John Garry <john.garry@huawei.com> Tested-by: Jin Yao <yao.jin@linux.intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kajol Jain <kjain@linux.ibm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lore.kernel.org/lkml/1626793819-79090-1-git-send-email-john.garry@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| * perf cs-etm: Split --dump-raw-trace by AUX recordsJames Clark2021-07-271-2/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently --dump-raw-trace skips queueing and splitting buffers because of an early exit condition in cs_etm__process_auxtrace_info(). Once that is removed we can print the split data by using the queues and searching for split buffers with the same reference as the one that is currently being processed. This keeps the same behaviour of dumping in file order when an AUXTRACE event appears, rather than moving trace dump to where AUX records are in the file. There will be a newline and size printout for each fragment. For example this buffer is comprised of two AUX records, but was printed as one: 0 0 0x8098 [0x30]: PERF_RECORD_AUXTRACE size: 0xa0 offset: 0 ref: 0x491a4dfc52fc0e6e idx: 0 t . ... CoreSight ETM Trace data: size 160 bytes Idx:0; ID:10; I_ASYNC : Alignment Synchronisation. Idx:12; ID:10; I_TRACE_INFO : Trace Info.; INFO=0x0 { CC.0 } Idx:17; ID:10; I_ADDR_L_64IS0 : Address, Long, 64 bit, IS0.; Addr=0x0000000000000000; Idx:80; ID:10; I_ASYNC : Alignment Synchronisation. Idx:92; ID:10; I_TRACE_INFO : Trace Info.; INFO=0x0 { CC.0 } Idx:97; ID:10; I_ADDR_L_64IS0 : Address, Long, 64 bit, IS0.; Addr=0xFFFFDE2AD3FD76D4; But is now printed as two fragments: 0 0 0x8098 [0x30]: PERF_RECORD_AUXTRACE size: 0xa0 offset: 0 ref: 0x491a4dfc52fc0e6e idx: 0 t . ... CoreSight ETM Trace data: size 80 bytes Idx:0; ID:10; I_ASYNC : Alignment Synchronisation. Idx:12; ID:10; I_TRACE_INFO : Trace Info.; INFO=0x0 { CC.0 } Idx:17; ID:10; I_ADDR_L_64IS0 : Address, Long, 64 bit, IS0.; Addr=0x0000000000000000; . ... CoreSight ETM Trace data: size 80 bytes Idx:80; ID:10; I_ASYNC : Alignment Synchronisation. Idx:92; ID:10; I_TRACE_INFO : Trace Info.; INFO=0x0 { CC.0 } Idx:97; ID:10; I_ADDR_L_64IS0 : Address, Long, 64 bit, IS0.; Addr=0xFFFFDE2AD3FD76D4; Decoding errors that appeared in problematic files are now not present, for example: Idx:808; ID:1c; I_BAD_SEQUENCE : Invalid Sequence in packet.[I_ASYNC] ... PKTP_ETMV4I_0016 : 0x0014 (OCSD_ERR_INVALID_PCKT_HDR) [Invalid packet header]; TrcIdx=822 Signed-off-by: James Clark <james.clark@arm.com> Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org> Tested-by: Leo Yan <leo.yan@linaro.org> Cc: Al Grant <al.grant@arm.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Branislav Rankov <branislav.rankov@arm.com> Cc: Denis Nikitin <denik@chromium.org> Cc: Jiri Olsa <jolsa@redhat.com> Cc: John Garry <john.garry@huawei.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mike Leach <mike.leach@linaro.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Suzuki Poulouse <suzuki.poulose@arm.com> Cc: Will Deacon <will@kernel.org> Cc: coresight@lists.linaro.org Cc: linux-arm-kernel@lists.infradead.org Link: http://lore.kernel.org/lkml/20210624164303.28632-3-james.clark@arm.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* | Merge tag 'powerpc-5.14-4' of ↵Linus Torvalds2021-08-012-1/+8
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc fixes from Michael Ellerman: - Don't use r30 in VDSO code, to avoid breaking existing Go lang programs. - Change an export symbol to allow non-GPL modules to use spinlocks again. Thanks to Paul Menzel, and Srikar Dronamraju. * tag 'powerpc-5.14-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: powerpc/vdso: Don't use r30 to avoid breaking Go lang powerpc/pseries: Fix regression while building external modules
| * | powerpc/vdso: Don't use r30 to avoid breaking Go langMichael Ellerman2021-07-291-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The Go runtime uses r30 for some special value called 'g'. It assumes that value will remain unchanged even when calling VDSO functions. Although r30 is non-volatile across function calls, the callee is free to use it, as long as the callee saves the value and restores it before returning. It used to be true by accident that the VDSO didn't use r30, because the VDSO was hand-written asm. When we switched to building the VDSO from C the compiler started using r30, at least in some builds, leading to crashes in Go. eg: ~/go/src$ ./all.bash Building Go cmd/dist using /usr/lib/go-1.16. (go1.16.2 linux/ppc64le) Building Go toolchain1 using /usr/lib/go-1.16. go build os/exec: /usr/lib/go-1.16/pkg/tool/linux_ppc64le/compile: signal: segmentation fault go build reflect: /usr/lib/go-1.16/pkg/tool/linux_ppc64le/compile: signal: segmentation fault go tool dist: FAILED: /usr/lib/go-1.16/bin/go install -gcflags=-l -tags=math_big_pure_go compiler_bootstrap bootstrap/cmd/...: exit status 1 There are patches in flight to fix Go[1], but until they are released and widely deployed we can workaround it in the VDSO by avoiding use of r30. Note this only works with GCC, clang does not support -ffixed-rN. 1: https://go-review.googlesource.com/c/go/+/328110 Fixes: ab037dd87a2f ("powerpc/vdso: Switch VDSO to generic C implementation.") Cc: stable@vger.kernel.org # v5.11+ Reported-by: Paul Menzel <pmenzel@molgen.mpg.de> Tested-by: Paul Menzel <pmenzel@molgen.mpg.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210729131244.2595519-1-mpe@ellerman.id.au
| * | powerpc/pseries: Fix regression while building external modulesSrikar Dronamraju2021-07-291-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With commit c9f3401313a5 ("powerpc: Always enable queued spinlocks for 64s, disable for others") CONFIG_PPC_QUEUED_SPINLOCKS is always enabled on ppc64le, external modules that use spinlock APIs are failing. ERROR: modpost: GPL-incompatible module XXX.ko uses GPL-only symbol 'shared_processor' Before the above commit, modules were able to build without any issues. Also this problem is not seen on other architectures. This problem can be workaround if CONFIG_UNINLINE_SPIN_UNLOCK is enabled in the config. However CONFIG_UNINLINE_SPIN_UNLOCK is not enabled by default and only enabled in certain conditions like CONFIG_DEBUG_SPINLOCKS is set in the kernel config. #include <linux/module.h> spinlock_t spLock; static int __init spinlock_test_init(void) { spin_lock_init(&spLock); spin_lock(&spLock); spin_unlock(&spLock); return 0; } static void __exit spinlock_test_exit(void) { printk("spinlock_test unloaded\n"); } module_init(spinlock_test_init); module_exit(spinlock_test_exit); MODULE_DESCRIPTION ("spinlock_test"); MODULE_LICENSE ("non-GPL"); MODULE_AUTHOR ("Srikar Dronamraju"); Given that spin locks are one of the basic facilities for module code, this effectively makes it impossible to build/load almost any non GPL modules on ppc64le. This was first reported at https://github.com/openzfs/zfs/issues/11172 Currently shared_processor is exported as GPL only symbol. Fix this for parity with other architectures by exposing shared_processor to non-GPL modules too. Fixes: 14c73bd344da ("powerpc/vcpu: Assume dedicated processors as non-preempt") Cc: stable@vger.kernel.org # v5.5+ Reported-by: marc.c.dionne@gmail.com Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210729060449.292780-1-srikar@linux.vnet.ibm.com
| * | Merge branch 'fixes' into nextMichael Ellerman2021-07-265-8/+68
| |\ \ | | | | | | | | | | | | | | | | Merge our fixes branch, which contains some fixes that didn't make it into rc2 but which we'd like in next.
* | \ \ Merge tag 'xfs-5.14-fixes-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linuxLinus Torvalds2021-08-017-106/+244
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull xfs fixes from Darrick Wong: "This contains a bunch of bug fixes in XFS. Dave and I have been busy the last couple of weeks to find and fix as many log recovery bugs as we can find; here are the results so far. Go fstests -g recoveryloop! ;) - Fix a number of coordination bugs relating to cache flushes for metadata writeback, cache flushes for multi-buffer log writes, and FUA writes for single-buffer log writes - Fix a bug with incorrect replay of attr3 blocks - Fix unnecessary stalls when flushing logs to disk - Fix spoofing problems when recovering realtime bitmap blocks" * tag 'xfs-5.14-fixes-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: xfs: prevent spoofing of rtbitmap blocks when recovering buffers xfs: limit iclog tail updates xfs: need to see iclog flags in tracing xfs: Enforce attr3 buffer recovery order xfs: logging the on disk inode LSN can make it go backwards xfs: avoid unnecessary waits in xfs_log_force_lsn() xfs: log forces imply data device cache flushes xfs: factor out forced iclog flushes xfs: fix ordering violation between cache flushes and tail updates xfs: fold __xlog_state_release_iclog into xlog_state_release_iclog xfs: external logs need to flush data device xfs: flush data dev on external log write
| * | | | xfs: prevent spoofing of rtbitmap blocks when recovering buffersDarrick J. Wong2021-07-291-2/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | While reviewing the buffer item recovery code, the thought occurred to me: in V5 filesystems we use log sequence number (LSN) tracking to avoid replaying older metadata updates against newer log items. However, we use the magic number of the ondisk buffer to find the LSN of the ondisk metadata, which means that if an attacker can control the layout of the realtime device precisely enough that the start of an rt bitmap block matches the magic and UUID of some other kind of block, they can control the purported LSN of that spoofed block and thereby break log replay. Since realtime bitmap and summary blocks don't have headers at all, we have no way to tell if a block really should be replayed. The best we can do is replay unconditionally and hope for the best. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
| * | | | xfs: limit iclog tail updatesDave Chinner2021-07-291-13/+37
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | From the department of "generic/482 keeps on giving", we bring you another tail update race condition: iclog: S1 C1 +-----------------------+-----------------------+ S2 EOIC Two checkpoints in a single iclog. One is complete, the other just contains the start record and overruns into a new iclog. Timeline: Before S1: Cache flush, log tail = X At S1: Metadata stable, write start record and checkpoint At C1: Write commit record, set NEED_FUA Single iclog checkpoint, so no need for NEED_FLUSH Log tail still = X, so no need for NEED_FLUSH After C1, Before S2: Cache flush, log tail = X At S2: Metadata stable, write start record and checkpoint After S2: Log tail moves to X+1 At EOIC: End of iclog, more journal data to write Releases iclog Not a commit iclog, so no need for NEED_FLUSH Writes log tail X+1 into iclog. At this point, the iclog has tail X+1 and NEED_FUA set. There has been no cache flush for the metadata between X and X+1, and the iclog writes the new tail permanently to the log. THis is sufficient to violate on disk metadata/journal ordering. We have two options here. The first is to detect this case in some manner and ensure that the partial checkpoint write sets NEED_FLUSH when the iclog is already marked NEED_FUA and the log tail changes. This seems somewhat fragile and quite complex to get right, and it doesn't actually make it obvious what underlying problem it is actually addressing from reading the code. The second option seems much cleaner to me, because it is derived directly from the requirements of the C1 commit record in the iclog. That is, when we write this commit record to the iclog, we've guaranteed that the metadata/data ordering is correct for tail update purposes. Hence if we only write the log tail into the iclog for the *first* commit record rather than the log tail at the last release, we guarantee that the log tail does not move past where the the first commit record in the log expects it to be. IOWs, taking the first option means that replay of C1 becomes dependent on future operations doing the right thing, not just the C1 checkpoint itself doing the right thing. This makes log recovery almost impossible to reason about because now we have to take into account what might or might not have happened in the future when looking at checkpoints in the log rather than just having to reconstruct the past... Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
| * | | | xfs: need to see iclog flags in tracingDave Chinner2021-07-292-4/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Because I cannot tell if the NEED_FLUSH flag is being set correctly by the log force and CIL push machinery without it. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
| * | | | xfs: Enforce attr3 buffer recovery orderDave Chinner2021-07-291-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | From the department of "WTAF? How did we miss that!?"... When we are recovering a buffer, the first thing we do is check the buffer magic number and extract the LSN from the buffer. If the LSN is older than the current LSN, we replay the modification to it. If the metadata on disk is newer than the transaction in the log, we skip it. This is a fundamental v5 filesystem metadata recovery behaviour. generic/482 failed with an attribute writeback failure during log recovery. The write verifier caught the corruption before it got written to disk, and the attr buffer dump looked like: XFS (dm-3): Metadata corruption detected at xfs_attr3_leaf_verify+0x275/0x2e0, xfs_attr3_leaf block 0x19be8 XFS (dm-3): Unmount and run xfs_repair XFS (dm-3): First 128 bytes of corrupted metadata buffer: 00000000: 00 00 00 00 00 00 00 00 3b ee 00 00 4d 2a 01 e1 ........;...M*.. 00000010: 00 00 00 00 00 01 9b e8 00 00 00 01 00 00 05 38 ...............8 ^^^^^^^^^^^^^^^^^^^^^^^ 00000020: df 39 5e 51 58 ac 44 b6 8d c5 e7 10 44 09 bc 17 .9^QX.D.....D... 00000030: 00 00 00 00 00 02 00 83 00 03 00 cc 0f 24 01 00 .............$.. 00000040: 00 68 0e bc 0f c8 00 10 00 00 00 00 00 00 00 00 .h.............. 00000050: 00 00 3c 31 0f 24 01 00 00 00 3c 32 0f 88 01 00 ..<1.$....<2.... 00000060: 00 00 3c 33 0f d8 01 00 00 00 00 00 00 00 00 00 ..<3............ 00000070: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ ..... The highlighted bytes are the LSN that was replayed into the buffer: 0x100000538. This is cycle 1, block 0x538. Prior to replay, that block on disk looks like this: $ sudo xfs_db -c "fsb 0x417d" -c "type attr3" -c p /dev/mapper/thin-vol hdr.info.hdr.forw = 0 hdr.info.hdr.back = 0 hdr.info.hdr.magic = 0x3bee hdr.info.crc = 0xb5af0bc6 (correct) hdr.info.bno = 105448 hdr.info.lsn = 0x100000900 ^^^^^^^^^^^ hdr.info.uuid = df395e51-58ac-44b6-8dc5-e7104409bc17 hdr.info.owner = 131203 hdr.count = 2 hdr.usedbytes = 120 hdr.firstused = 3796 hdr.holes = 1 hdr.freemap[0-2] = [base,size] Note the LSN stamped into the buffer on disk: 1/0x900. The version on disk is much newer than the log transaction that was being replayed. That's a bug, and should -never- happen. So I immediately went to look at xlog_recover_get_buf_lsn() to check that we handled the LSN correctly. I was wondering if there was a similar "two commits with the same start LSN skips the second replay" problem with buffers. I didn't get that far, because I found a much more basic, rudimentary bug: xlog_recover_get_buf_lsn() doesn't recognise buffers with XFS_ATTR3_LEAF_MAGIC set in them!!! IOWs, attr3 leaf buffers fall through the magic number checks unrecognised, so trigger the "recover immediately" behaviour instead of undergoing an LSN check. IOWs, we incorrectly replay ATTR3 leaf buffers and that causes silent on disk corruption of inode attribute forks and potentially other things.... Git history shows this is *another* zero day bug, this time introduced in commit 50d5c8d8e938 ("xfs: check LSN ordering for v5 superblocks during recovery") which failed to handle the attr3 leaf buffers in recovery. And we've failed to handle them ever since... Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
| * | | | xfs: logging the on disk inode LSN can make it go backwardsDave Chinner2021-07-292-11/+39
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When we log an inode, we format the "log inode" core and set an LSN in that inode core. We do that via xfs_inode_item_format_core(), which calls: xfs_inode_to_log_dinode(ip, dic, ip->i_itemp->ili_item.li_lsn); to format the log inode. It writes the LSN from the inode item into the log inode, and if recovery decides the inode item needs to be replayed, it recovers the log inode LSN field and writes it into the on disk inode LSN field. Now this might seem like a reasonable thing to do, but it is wrong on multiple levels. Firstly, if the item is not yet in the AIL, item->li_lsn is zero. i.e. the first time the inode it is logged and formatted, the LSN we write into the log inode will be zero. If we only log it once, recovery will run and can write this zero LSN into the inode. This means that the next time the inode is logged and log recovery runs, it will *always* replay changes to the inode regardless of whether the inode is newer on disk than the version in the log and that violates the entire purpose of recording the LSN in the inode at writeback time (i.e. to stop it going backwards in time on disk during recovery). Secondly, if we commit the CIL to the journal so the inode item moves to the AIL, and then relog the inode, the LSN that gets stamped into the log inode will be the LSN of the inode's current location in the AIL, not it's age on disk. And it's not the LSN that will be associated with the current change. That means when log recovery replays this inode item, the LSN that ends up on disk is the LSN for the previous changes in the log, not the current changes being replayed. IOWs, after recovery the LSN on disk is not in sync with the LSN of the modifications that were replayed into the inode. This, again, violates the recovery ordering semantics that on-disk writeback LSNs provide. Hence the inode LSN in the log dinode is -always- invalid. Thirdly, recovery actually has the LSN of the log transaction it is replaying right at hand - it uses it to determine if it should replay the inode by comparing it to the on-disk inode's LSN. But it doesn't use that LSN to stamp the LSN into the inode which will be written back when the transaction is fully replayed. It uses the one in the log dinode, which we know is always going to be incorrect. Looking back at the change history, the inode logging was broken by commit 93f958f9c41f ("xfs: cull unnecessary icdinode fields") way back in 2016 by a stupid idiot who thought he knew how this code worked. i.e. me. That commit replaced an in memory di_lsn field that was updated only at inode writeback time from the inode item.li_lsn value - and hence always contained the same LSN that appeared in the on-disk inode - with a read of the inode item LSN at inode format time. CLearly these are not the same thing. Before 93f958f9c41f, the log recovery behaviour was irrelevant, because the LSN in the log inode always matched the on-disk LSN at the time the inode was logged, hence recovery of the transaction would never make the on-disk LSN in the inode go backwards or get out of sync. A symptom of the problem is this, caught from a failure of generic/482. Before log recovery, the inode has been allocated but never used: xfs_db> inode 393388 xfs_db> p core.magic = 0x494e core.mode = 0 .... v3.crc = 0x99126961 (correct) v3.change_count = 0 v3.lsn = 0 v3.flags2 = 0 v3.cowextsize = 0 v3.crtime.sec = Thu Jan 1 10:00:00 1970 v3.crtime.nsec = 0 After log recovery: xfs_db> p core.magic = 0x494e core.mode = 020444 .... v3.crc = 0x23e68f23 (correct) v3.change_count = 2 v3.lsn = 0 v3.flags2 = 0 v3.cowextsize = 0 v3.crtime.sec = Thu Jul 22 17:03:03 2021 v3.crtime.nsec = 751000000 ... You can see that the LSN of the on-disk inode is 0, even though it clearly has been written to disk. I point out this inode, because the generic/482 failure occurred because several adjacent inodes in this specific inode cluster were not replayed correctly and still appeared to be zero on disk when all the other metadata (inobt, finobt, directories, etc) indicated they should be allocated and written back. The fix for this is two-fold. The first is that we need to either revert the LSN changes in 93f958f9c41f or stop logging the inode LSN altogether. If we do the former, log recovery does not need to change but we add 8 bytes of memory per inode to store what is largely a write-only inode field. If we do the latter, log recovery needs to stamp the on-disk inode in the same manner that inode writeback does. I prefer the latter, because we shouldn't really be trying to log and replay changes to the on disk LSN as the on-disk value is the canonical source of the on-disk version of the inode. It also matches the way we recover buffer items - we create a buf_log_item that carries the current recovery transaction LSN that gets stamped into the buffer by the write verifier when it gets written back when the transaction is fully recovered. However, this might break log recovery on older kernels even more, so I'm going to simply ignore the logged value in recovery and stamp the on-disk inode with the LSN of the transaction being recovered that will trigger writeback on transaction recovery completion. This will ensure that the on-disk inode LSN always reflects the LSN of the last change that was written to disk, regardless of whether it comes from log recovery or runtime writeback. Fixes: 93f958f9c41f ("xfs: cull unnecessary icdinode fields") Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
| * | | | xfs: avoid unnecessary waits in xfs_log_force_lsn()Dave Chinner2021-07-291-5/+37
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Before waiting on a iclog in xfs_log_force_lsn(), we don't check to see if the iclog has already been completed and the contents on stable storage. We check for completed iclogs in xfs_log_force(), so we should do the same thing for xfs_log_force_lsn(). This fixed some random up-to-30s pauses seen in unmounting filesystems in some tests. A log force ends up waiting on completed iclog, and that doesn't then get flushed (and hence the log force get completed) until the background log worker issues a log force that flushes the iclog in question. Then the unmount unblocks and continues. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
| * | | | xfs: log forces imply data device cache flushesDave Chinner2021-07-291-13/+34
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | After fixing the tail_lsn vs cache flush race, generic/482 continued to fail in a similar way where cache flushes were missing before iclog FUA writes. Tracing of iclog state changes during the fsstress workload portion of the test (via xlog_iclog* events) indicated that iclog writes were coming from two sources - CIL pushes and log forces (due to fsync/O_SYNC operations). All of the cases where a recovery problem was triggered indicated that the log force was the source of the iclog write that was not preceeded by a cache flush. This was an oversight in the modifications made in commit eef983ffeae7 ("xfs: journal IO cache flush reductions"). Log forces for fsync imply a data device cache flush has been issued if an iclog was flushed to disk and is indicated to the caller via the log_flushed parameter so they can elide the device cache flush if the journal issued one. The change in eef983ffeae7 results in iclogs only issuing a cache flush if XLOG_ICL_NEED_FLUSH is set on the iclog, but this was not added to the iclogs that the log force code flushes to disk. Hence log forces are no longer guaranteeing that a cache flush is issued, hence opening up a potential on-disk ordering failure. Log forces should also set XLOG_ICL_NEED_FUA as well to ensure that the actual iclogs it forces to the journal are also on stable storage before it returns to the caller. This patch introduces the xlog_force_iclog() helper function to encapsulate the process of taking a reference to an iclog, switching its state if WANT_SYNC and flushing it to stable storage correctly. Both xfs_log_force() and xfs_log_force_lsn() are converted to use it, as is xlog_unmount_write() which has an elaborate method of doing exactly the same "write this iclog to stable storage" operation. Further, if the log force code needs to wait on a iclog in the WANT_SYNC state, it needs to ensure that iclog also results in a cache flush being issued. This covers the case where the iclog contains the commit record of the CIL flush that the log force triggered, but it hasn't been written yet because there is still an active reference to the iclog. Note: this whole cache flush whack-a-mole patch is a result of log forces still being iclog state centric rather than being CIL sequence centric. Most of this nasty code will go away in future when log forces are converted to wait on CIL sequence push completion rather than iclog completion. With the CIL push algorithm guaranteeing that the CIL checkpoint is fully on stable storage when it completes, we no longer need to iterate iclogs and push them to ensure a CIL sequence push has completed and so all this nasty iclog iteration and flushing code will go away. Fixes: eef983ffeae7 ("xfs: journal IO cache flush reductions") Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
| * | | | xfs: factor out forced iclog flushesDave Chinner2021-07-291-24/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We force iclogs in several places - we need them all to have the same cache flush semantics, so start by factoring out the iclog force into a common helper. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
| * | | | xfs: fix ordering violation between cache flushes and tail updatesDave Chinner2021-07-293-13/+39
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There is a race between the new CIL async data device metadata IO completion cache flush and the log tail in the iclog the flush covers being updated. This can be seen by repeating generic/482 in a loop and eventually log recovery fails with a failures such as this: XFS (dm-3): Starting recovery (logdev: internal) XFS (dm-3): bad inode magic/vsn daddr 228352 #0 (magic=0) XFS (dm-3): Metadata corruption detected at xfs_inode_buf_verify+0x180/0x190, xfs_inode block 0x37c00 xfs_inode_buf_verify XFS (dm-3): Unmount and run xfs_repair XFS (dm-3): First 128 bytes of corrupted metadata buffer: 00000000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000010: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000020: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000030: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000040: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000050: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000060: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000070: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ XFS (dm-3): metadata I/O error in "xlog_recover_items_pass2+0x55/0xc0" at daddr 0x37c00 len 32 error 117 Analysis of the logwrite replay shows that there were no writes to the data device between the FUA @ write 124 and the FUA at write @ 125, but log recovery @ 125 failed. The difference was the one log write @ 125 moved the tail of the log forwards from (1,8) to (1,32) and so the inode create intent in (1,8) was not replayed and so the inode cluster was zero on disk when replay of the first inode item in (1,32) was attempted. What this meant was that the journal write that occurred at @ 125 did not ensure that metadata completed before the iclog was written was correctly on stable storage. The tail of the log moved forward, so IO must have been completed between the two iclog writes. This means that there is a race condition between the unconditional async cache flush in the CIL push work and the tail LSN that is written to the iclog. This happens like so: CIL push work AIL push work ------------- ------------- Add to committing list start async data dev cache flush ..... <flush completes> <all writes to old tail lsn are stable> xlog_write .... push inode create buffer <start IO> ..... xlog_write(commit record) .... <IO completes> log tail moves xlog_assign_tail_lsn() start_lsn == commit_lsn <no iclog preflush!> xlog_state_release_iclog __xlog_state_release_iclog() <writes *new* tail_lsn into iclog> xlog_sync() .... submit_bio() <tail in log moves forward without flushing written metadata> Essentially, this can only occur if the commit iclog is issued without a cache flush. If the iclog bio is submitted with REQ_PREFLUSH, then it will guarantee that all the completed IO is one stable storage before the iclog bio with the new tail LSN in it is written to the log. IOWs, the tail lsn that is written to the iclog needs to be sampled *before* we issue the cache flush that guarantees all IO up to that LSN has been completed. To fix this without giving up the performance advantage of the flush/FUA optimisations (e.g. g/482 runtime halves with 5.14-rc1 compared to 5.13), we need to ensure that we always issue a cache flush if the tail LSN changes between the initial async flush and the commit record being written. THis requires sampling the tail_lsn before we start the flush, and then passing the sampled tail LSN to xlog_state_release_iclog() so it can determine if the the tail LSN has changed while writing the checkpoint. If the tail LSN has changed, then it needs to set the NEED_FLUSH flag on the iclog and we'll issue another cache flush before writing the iclog. Fixes: eef983ffeae7 ("xfs: journal IO cache flush reductions") Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
| * | | | xfs: fold __xlog_state_release_iclog into xlog_state_release_iclogDave Chinner2021-07-291-28/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fold __xlog_state_release_iclog into its only caller to prepare make an upcoming fix easier. Signed-off-by: Dave Chinner <dchinner@redhat.com> [hch: split from a larger patch] Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
| * | | | xfs: external logs need to flush data deviceDave Chinner2021-07-291-8/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The recent journal flush/FUA changes replaced the flushing of the data device on every iclog write with an up-front async data device cache flush. Unfortunately, the assumption of which this was based on has been proven incorrect by the flush vs log tail update ordering issue. As the fix for that issue uses the XLOG_ICL_NEED_FLUSH flag to indicate that data device needs a cache flush, we now need to (once again) ensure that an iclog write to external logs that need a cache flush to be issued actually issue a cache flush to the data device as well as the log device. Fixes: eef983ffeae7 ("xfs: journal IO cache flush reductions") Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
| * | | | xfs: flush data dev on external log writeDave Chinner2021-07-291-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We incorrectly flush the log device instead of the data device when trying to ensure metadata is correctly on disk before writing the unmount record. Fixes: eef983ffeae7 ("xfs: journal IO cache flush reductions") Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
* | | | | Merge tag '5.14-rc3-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6Linus Torvalds2021-07-313-2/+10
|\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull cifs fixes from Steve French: "Three cifs/smb3 fixes, including two for stable, and a fix for an fallocate problem noticed by Clang" * tag '5.14-rc3-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6: cifs: add missing parsing of backupuid smb3: rc uninitialized in one fallocate path SMB3: fix readpage for large swap cache
| * | | | | cifs: add missing parsing of backupuidRonnie Sahlberg2021-07-291-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We lost parsing of backupuid in the switch to new mount API. Add it back. Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Reviewed-by: Shyam Prasad N <sprasad@microsoft.com> Cc: <stable@vger.kernel.org> # v5.11+ Reported-by: Xiaoli Feng <xifeng@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com>
| * | | | | smb3: rc uninitialized in one fallocate pathSteve French2021-07-271-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Clang detected a problem with rc possibly being unitialized (when length is zero) in a recently added fallocate code path. Reported-by: kernel test robot <lkp@intel.com> Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz> Signed-off-by: Steve French <stfrench@microsoft.com>
| * | | | | SMB3: fix readpage for large swap cacheSteve French2021-07-271-1/+1
| | |_|_|/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | readpage was calculating the offset of the page incorrectly for the case of large swapcaches. loff_t offset = (loff_t)page->index << PAGE_SHIFT; As pointed out by Matthew Wilcox, this needs to use page_file_offset() to calculate the offset instead. Pages coming from the swap cache have page->index set to their index within the swapcache, not within the backing file. For a sufficiently large swapcache, we could have overlapping values of page->index within the same backing file. Suggested by: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: <stable@vger.kernel.org> # v5.7+ Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com>
* | | | | Merge tag 'net-5.14-rc4' of ↵Linus Torvalds2021-07-31104-547/+1230
|\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net Pull networking fixes from Jakub Kicinski: "Networking fixes for 5.14-rc4, including fixes from bpf, can, WiFi (mac80211) and netfilter trees. Current release - regressions: - mac80211: fix starting aggregation sessions on mesh interfaces Current release - new code bugs: - sctp: send pmtu probe only if packet loss in Search Complete state - bnxt_en: add missing periodic PHC overflow check - devlink: fix phys_port_name of virtual port and merge error - hns3: change the method of obtaining default ptp cycle - can: mcba_usb_start(): add missing urb->transfer_dma initialization Previous releases - regressions: - set true network header for ECN decapsulation - mlx5e: RX, avoid possible data corruption w/ relaxed ordering and LRO - phy: re-add check for PHY_BRCM_DIS_TXCRXC_NOENRGY on the BCM54811 PHY - sctp: fix return value check in __sctp_rcv_asconf_lookup Previous releases - always broken: - bpf: - more spectre corner case fixes, introduce a BPF nospec instruction for mitigating Spectre v4 - fix OOB read when printing XDP link fdinfo - sockmap: fix cleanup related races - mac80211: fix enabling 4-address mode on a sta vif after assoc - can: - raw: raw_setsockopt(): fix raw_rcv panic for sock UAF - j1939: j1939_session_deactivate(): clarify lifetime of session object, avoid UAF - fix number of identical memory leaks in USB drivers - tipc: - do not blindly write skb_shinfo frags when doing decryption - fix sleeping in tipc accept routine" * tag 'net-5.14-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (91 commits) gve: Update MAINTAINERS list can: esd_usb2: fix memory leak can: ems_usb: fix memory leak can: usb_8dev: fix memory leak can: mcba_usb_start(): add missing urb->transfer_dma initialization can: hi311x: fix a signedness bug in hi3110_cmd() MAINTAINERS: add Yasushi SHOJI as reviewer for the Microchip CAN BUS Analyzer Tool driver bpf: Fix leakage due to insufficient speculative store bypass mitigation bpf: Introduce BPF nospec instruction for mitigating Spectre v4 sis900: Fix missing pci_disable_device() in probe and remove net: let flow have same hash in two directions nfc: nfcsim: fix use after free during module unload tulip: windbond-840: Fix missing pci_disable_device() in probe and remove sctp: fix return value check in __sctp_rcv_asconf_lookup nfc: s3fwrn5: fix undefined parameter values in dev_err() net/mlx5: Fix mlx5_vport_tbl_attr chain from u16 to u32 net/mlx5e: Fix nullptr in mlx5e_hairpin_get_mdev() net/mlx5: Unload device upon firmware fatal error net/mlx5e: Fix page allocation failure for ptp-RQ over SF net/mlx5e: Fix page allocation failure for trap-RQ over SF ...
| * \ \ \ \ Merge tag 'linux-can-fixes-for-5.14-20210730' of ↵Jakub Kicinski2021-07-306-5/+50
| |\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can Marc Kleine-Budde says: ==================== pull-request: can 2021-07-30 The first patch is by me and adds Yasushi SHOJI as a reviewer for the Microchip CAN BUS Analyzer Tool driver. Dan Carpenter's patch fixes a signedness bug in the hi311x driver. Pavel Skripkin provides 4 patches, the first targets the mcba_usb driver by adding the missing urb->transfer_dma initialization, which was broken in a previous commit. The last 3 patches fix a memory leak in the usb_8dev, ems_usb and esd_usb2 driver. * tag 'linux-can-fixes-for-5.14-20210730' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can: can: esd_usb2: fix memory leak can: ems_usb: fix memory leak can: usb_8dev: fix memory leak can: mcba_usb_start(): add missing urb->transfer_dma initialization can: hi311x: fix a signedness bug in hi3110_cmd() MAINTAINERS: add Yasushi SHOJI as reviewer for the Microchip CAN BUS Analyzer Tool driver ==================== Link: https://lore.kernel.org/r/20210730070526.1699867-1-mkl@pengutronix.de Signed-off-by: Jakub Kicinski <kuba@kernel.org>
| | * | | | | can: esd_usb2: fix memory leakPavel Skripkin2021-07-301-1/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In esd_usb2_setup_rx_urbs() MAX_RX_URBS coherent buffers are allocated and there is nothing, that frees them: 1) In callback function the urb is resubmitted and that's all 2) In disconnect function urbs are simply killed, but URB_FREE_BUFFER is not set (see esd_usb2_setup_rx_urbs) and this flag cannot be used with coherent buffers. So, all allocated buffers should be freed with usb_free_coherent() explicitly. Side note: This code looks like a copy-paste of other can drivers. The same patch was applied to mcba_usb driver and it works nice with real hardware. There is no change in functionality, only clean-up code for coherent buffers. Fixes: 96d8e90382dc ("can: Add driver for esd CAN-USB/2 device") Link: https://lore.kernel.org/r/b31b096926dcb35998ad0271aac4b51770ca7cc8.1627404470.git.paskripkin@gmail.com Cc: linux-stable <stable@vger.kernel.org> Signed-off-by: Pavel Skripkin <paskripkin@gmail.com> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
| | * | | | | can: ems_usb: fix memory leakPavel Skripkin2021-07-301-1/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In ems_usb_start() MAX_RX_URBS coherent buffers are allocated and there is nothing, that frees them: 1) In callback function the urb is resubmitted and that's all 2) In disconnect function urbs are simply killed, but URB_FREE_BUFFER is not set (see ems_usb_start) and this flag cannot be used with coherent buffers. So, all allocated buffers should be freed with usb_free_coherent() explicitly. Side note: This code looks like a copy-paste of other can drivers. The same patch was applied to mcba_usb driver and it works nice with real hardware. There is no change in functionality, only clean-up code for coherent buffers. Fixes: 702171adeed3 ("ems_usb: Added support for EMS CPC-USB/ARM7 CAN/USB interface") Link: https://lore.kernel.org/r/59aa9fbc9a8cbf9af2bbd2f61a659c480b415800.1627404470.git.paskripkin@gmail.com Cc: linux-stable <stable@vger.kernel.org> Signed-off-by: Pavel Skripkin <paskripkin@gmail.com> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
| | * | | | | can: usb_8dev: fix memory leakPavel Skripkin2021-07-301-2/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In usb_8dev_start() MAX_RX_URBS coherent buffers are allocated and there is nothing, that frees them: 1) In callback function the urb is resubmitted and that's all 2) In disconnect function urbs are simply killed, but URB_FREE_BUFFER is not set (see usb_8dev_start) and this flag cannot be used with coherent buffers. So, all allocated buffers should be freed with usb_free_coherent() explicitly. Side note: This code looks like a copy-paste of other can drivers. The same patch was applied to mcba_usb driver and it works nice with real hardware. There is no change in functionality, only clean-up code for coherent buffers. Fixes: 0024d8ad1639 ("can: usb_8dev: Add support for USB2CAN interface from 8 devices") Link: https://lore.kernel.org/r/d39b458cd425a1cf7f512f340224e6e9563b07bd.1627404470.git.paskripkin@gmail.com Cc: linux-stable <stable@vger.kernel.org> Signed-off-by: Pavel Skripkin <paskripkin@gmail.com> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
| | * | | | | can: mcba_usb_start(): add missing urb->transfer_dma initializationPavel Skripkin2021-07-301-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Yasushi reported, that his Microchip CAN Analyzer stopped working since commit 91c02557174b ("can: mcba_usb: fix memory leak in mcba_usb"). The problem was in missing urb->transfer_dma initialization. In my previous patch to this driver I refactored mcba_usb_start() code to avoid leaking usb coherent buffers. To archive it, I passed local stack variable to usb_alloc_coherent() and then saved it to private array to correctly free all coherent buffers on ->close() call. But I forgot to initialize urb->transfer_dma with variable passed to usb_alloc_coherent(). All of this was causing device to not work, since dma addr 0 is not valid and following log can be found on bug report page, which points exactly to problem described above. | DMAR: [DMA Write] Request device [00:14.0] PASID ffffffff fault addr 0 [fault reason 05] PTE Write access is not set Fixes: 91c02557174b ("can: mcba_usb: fix memory leak in mcba_usb") Link: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=990850 Link: https://lore.kernel.org/r/20210725103630.23864-1-paskripkin@gmail.com Cc: linux-stable <stable@vger.kernel.org> Reported-by: Yasushi SHOJI <yasushi.shoji@gmail.com> Signed-off-by: Pavel Skripkin <paskripkin@gmail.com> Tested-by: Yasushi SHOJI <yashi@spacecubics.com> [mkl: fixed typos in commit message - thanks Yasushi SHOJI] Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
| | * | | | | can: hi311x: fix a signedness bug in hi3110_cmd()Dan Carpenter2021-07-301-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The hi3110_cmd() is supposed to return zero on success and negative error codes on failure, but it was accidentally declared as a u8 when it needs to be an int type. Fixes: 57e83fb9b746 ("can: hi311x: Add Holt HI-311x CAN driver") Link: https://lore.kernel.org/r/20210729141246.GA1267@kili Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
| | * | | | | MAINTAINERS: add Yasushi SHOJI as reviewer for the Microchip CAN BUS ↵Marc Kleine-Budde2021-07-301-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Analyzer Tool driver This patch adds Yasushi SHOJI as a reviewer for the Microchip CAN BUS Analyzer Tool driver. Link: https://lore.kernel.org/r/20210726111619.1023991-1-mkl@pengutronix.de Acked-by: Yasushi SHOJI <yashi@spacecubics.com> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
| * | | | | | gve: Update MAINTAINERS listCatherine Sullivan2021-07-301-3/+3
| |/ / / / / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The team maintaining the gve driver has undergone some changes, this updates the MAINTAINERS file accordingly. Signed-off-by: Catherine Sullivan <csully@google.com> Signed-off-by: Jon Olson <jonolson@google.com> Signed-off-by: David Awogbemila <awogbemila@google.com> Signed-off-by: Jeroen de Borst <jeroendb@google.com> Link: https://lore.kernel.org/r/20210729155258.442650-1-csully@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
| * | | | | Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpfDavid S. Miller2021-07-2920-138/+446
| |\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Daniel Borkmann says: ==================== pull-request: bpf 2021-07-29 The following pull-request contains BPF updates for your *net* tree. We've added 9 non-merge commits during the last 14 day(s) which contain a total of 20 files changed, 446 insertions(+), 138 deletions(-). The main changes are: 1) Fix UBSAN out-of-bounds splat for showing XDP link fdinfo, from Lorenz Bauer. 2) Fix insufficient Spectre v4 mitigation in BPF runtime, from Daniel Borkmann, Piotr Krysiuk and Benedict Schlueter. 3) Batch of fixes for BPF sockmap found under stress testing, from John Fastabend. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
| | * | | | | bpf: Fix leakage due to insufficient speculative store bypass mitigationDaniel Borkmann2021-07-292-56/+33
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Spectre v4 gadgets make use of memory disambiguation, which is a set of techniques that execute memory access instructions, that is, loads and stores, out of program order; Intel's optimization manual, section 2.4.4.5: A load instruction micro-op may depend on a preceding store. Many microarchitectures block loads until all preceding store addresses are known. The memory disambiguator predicts which loads will not depend on any previous stores. When the disambiguator predicts that a load does not have such a dependency, the load takes its data from the L1 data cache. Eventually, the prediction is verified. If an actual conflict is detected, the load and all succeeding instructions are re-executed. af86ca4e3088 ("bpf: Prevent memory disambiguation attack") tried to mitigate this attack by sanitizing the memory locations through preemptive "fast" (low latency) stores of zero prior to the actual "slow" (high latency) store of a pointer value such that upon dependency misprediction the CPU then speculatively executes the load of the pointer value and retrieves the zero value instead of the attacker controlled scalar value previously stored at that location, meaning, subsequent access in the speculative domain is then redirected to the "zero page". The sanitized preemptive store of zero prior to the actual "slow" store is done through a simple ST instruction based on r10 (frame pointer) with relative offset to the stack location that the verifier has been tracking on the original used register for STX, which does not have to be r10. Thus, there are no memory dependencies for this store, since it's only using r10 and immediate constant of zero; hence af86ca4e3088 /assumed/ a low latency operation. However, a recent attack demonstrated that this mitigation is not sufficient since the preemptive store of zero could also be turned into a "slow" store and is thus bypassed as well: [...] // r2 = oob address (e.g. scalar) // r7 = pointer to map value 31: (7b) *(u64 *)(r10 -16) = r2 // r9 will remain "fast" register, r10 will become "slow" register below 32: (bf) r9 = r10 // JIT maps BPF reg to x86 reg: // r9 -> r15 (callee saved) // r10 -> rbp // train store forward prediction to break dependency link between both r9 // and r10 by evicting them from the predictor's LRU table. 33: (61) r0 = *(u32 *)(r7 +24576) 34: (63) *(u32 *)(r7 +29696) = r0 35: (61) r0 = *(u32 *)(r7 +24580) 36: (63) *(u32 *)(r7 +29700) = r0 37: (61) r0 = *(u32 *)(r7 +24584) 38: (63) *(u32 *)(r7 +29704) = r0 39: (61) r0 = *(u32 *)(r7 +24588) 40: (63) *(u32 *)(r7 +29708) = r0 [...] 543: (61) r0 = *(u32 *)(r7 +25596) 544: (63) *(u32 *)(r7 +30716) = r0 // prepare call to bpf_ringbuf_output() helper. the latter will cause rbp // to spill to stack memory while r13/r14/r15 (all callee saved regs) remain // in hardware registers. rbp becomes slow due to push/pop latency. below is // disasm of bpf_ringbuf_output() helper for better visual context: // // ffffffff8117ee20: 41 54 push r12 // ffffffff8117ee22: 55 push rbp // ffffffff8117ee23: 53 push rbx // ffffffff8117ee24: 48 f7 c1 fc ff ff ff test rcx,0xfffffffffffffffc // ffffffff8117ee2b: 0f 85 af 00 00 00 jne ffffffff8117eee0 <-- jump taken // [...] // ffffffff8117eee0: 49 c7 c4 ea ff ff ff mov r12,0xffffffffffffffea // ffffffff8117eee7: 5b pop rbx // ffffffff8117eee8: 5d pop rbp // ffffffff8117eee9: 4c 89 e0 mov rax,r12 // ffffffff8117eeec: 41 5c pop r12 // ffffffff8117eeee: c3 ret 545: (18) r1 = map[id:4] 547: (bf) r2 = r7 548: (b7) r3 = 0 549: (b7) r4 = 4 550: (85) call bpf_ringbuf_output#194288 // instruction 551 inserted by verifier \ 551: (7a) *(u64 *)(r10 -16) = 0 | /both/ are now slow stores here // storing map value pointer r7 at fp-16 | since value of r10 is "slow". 552: (7b) *(u64 *)(r10 -16) = r7 / // following "fast" read to the same memory location, but due to dependency // misprediction it will speculatively execute before insn 551/552 completes. 553: (79) r2 = *(u64 *)(r9 -16) // in speculative domain contains attacker controlled r2. in non-speculative // domain this contains r7, and thus accesses r7 +0 below. 554: (71) r3 = *(u8 *)(r2 +0) // leak r3 As can be seen, the current speculative store bypass mitigation which the verifier inserts at line 551 is insufficient since /both/, the write of the zero sanitation as well as the map value pointer are a high latency instruction due to prior memory access via push/pop of r10 (rbp) in contrast to the low latency read in line 553 as r9 (r15) which stays in hardware registers. Thus, architecturally, fp-16 is r7, however, microarchitecturally, fp-16 can still be r2. Initial thoughts to address this issue was to track spilled pointer loads from stack and enforce their load via LDX through r10 as well so that /both/ the preemptive store of zero /as well as/ the load use the /same/ register such that a dependency is created between the store and load. However, this option is not sufficient either since it can be bypassed as well under speculation. An updated attack with pointer spill/fills now _all_ based on r10 would look as follows: [...] // r2 = oob address (e.g. scalar) // r7 = pointer to map value [...] // longer store forward prediction training sequence than before. 2062: (61) r0 = *(u32 *)(r7 +25588) 2063: (63) *(u32 *)(r7 +30708) = r0 2064: (61) r0 = *(u32 *)(r7 +25592) 2065: (63) *(u32 *)(r7 +30712) = r0 2066: (61) r0 = *(u32 *)(r7 +25596) 2067: (63) *(u32 *)(r7 +30716) = r0 // store the speculative load address (scalar) this time after the store // forward prediction training. 2068: (7b) *(u64 *)(r10 -16) = r2 // preoccupy the CPU store port by running sequence of dummy stores. 2069: (63) *(u32 *)(r7 +29696) = r0 2070: (63) *(u32 *)(r7 +29700) = r0 2071: (63) *(u32 *)(r7 +29704) = r0 2072: (63) *(u32 *)(r7 +29708) = r0 2073: (63) *(u32 *)(r7 +29712) = r0 2074: (63) *(u32 *)(r7 +29716) = r0 2075: (63) *(u32 *)(r7 +29720) = r0 2076: (63) *(u32 *)(r7 +29724) = r0 2077: (63) *(u32 *)(r7 +29728) = r0 2078: (63) *(u32 *)(r7 +29732) = r0 2079: (63) *(u32 *)(r7 +29736) = r0 2080: (63) *(u32 *)(r7 +29740) = r0 2081: (63) *(u32 *)(r7 +29744) = r0 2082: (63) *(u32 *)(r7 +29748) = r0 2083: (63) *(u32 *)(r7 +29752) = r0 2084: (63) *(u32 *)(r7 +29756) = r0 2085: (63) *(u32 *)(r7 +29760) = r0 2086: (63) *(u32 *)(r7 +29764) = r0 2087: (63) *(u32 *)(r7 +29768) = r0 2088: (63) *(u32 *)(r7 +29772) = r0 2089: (63) *(u32 *)(r7 +29776) = r0 2090: (63) *(u32 *)(r7 +29780) = r0 2091: (63) *(u32 *)(r7 +29784) = r0 2092: (63) *(u32 *)(r7 +29788) = r0 2093: (63) *(u32 *)(r7 +29792) = r0 2094: (63) *(u32 *)(r7 +29796) = r0 2095: (63) *(u32 *)(r7 +29800) = r0 2096: (63) *(u32 *)(r7 +29804) = r0 2097: (63) *(u32 *)(r7 +29808) = r0 2098: (63) *(u32 *)(r7 +29812) = r0 // overwrite scalar with dummy pointer; same as before, also including the // sanitation store with 0 from the current mitigation by the verifier. 2099: (7a) *(u64 *)(r10 -16) = 0 | /both/ are now slow stores here 2100: (7b) *(u64 *)(r10 -16) = r7 | since store unit is still busy. // load from stack intended to bypass stores. 2101: (79) r2 = *(u64 *)(r10 -16) 2102: (71) r3 = *(u8 *)(r2 +0) // leak r3 [...] Looking at the CPU microarchitecture, the scheduler might issue loads (such as seen in line 2101) before stores (line 2099,2100) because the load execution units become available while the store execution unit is still busy with the sequence of dummy stores (line 2069-2098). And so the load may use the prior stored scalar from r2 at address r10 -16 for speculation. The updated attack may work less reliable on CPU microarchitectures where loads and stores share execution resources. This concludes that the sanitizing with zero stores from af86ca4e3088 ("bpf: Prevent memory disambiguation attack") is insufficient. Moreover, the detection of stack reuse from af86ca4e3088 where previously data (STACK_MISC) has been written to a given stack slot where a pointer value is now to be stored does not have sufficient coverage as precondition for the mitigation either; for several reasons outlined as follows: 1) Stack content from prior program runs could still be preserved and is therefore not "random", best example is to split a speculative store bypass attack between tail calls, program A would prepare and store the oob address at a given stack slot and then tail call into program B which does the "slow" store of a pointer to the stack with subsequent "fast" read. From program B PoV such stack slot type is STACK_INVALID, and therefore also must be subject to mitigation. 2) The STACK_SPILL must not be coupled to register_is_const(&stack->spilled_ptr) condition, for example, the previous content of that memory location could also be a pointer to map or map value. Without the fix, a speculative store bypass is not mitigated in such precondition and can then lead to a type confusion in the speculative domain leaking kernel memory near these pointer types. While brainstorming on various alternative mitigation possibilities, we also stumbled upon a retrospective from Chrome developers [0]: [...] For variant 4, we implemented a mitigation to zero the unused memory of the heap prior to allocation, which cost about 1% when done concurrently and 4% for scavenging. Variant 4 defeats everything we could think of. We explored more mitigations for variant 4 but the threat proved to be more pervasive and dangerous than we anticipated. For example, stack slots used by the register allocator in the optimizing compiler could be subject to type confusion, leading to pointer crafting. Mitigating type confusion for stack slots alone would have required a complete redesign of the backend of the optimizing compiler, perhaps man years of work, without a guarantee of completeness. [...] From BPF side, the problem space is reduced, however, options are rather limited. One idea that has been explored was to xor-obfuscate pointer spills to the BPF stack: [...] // preoccupy the CPU store port by running sequence of dummy stores. [...] 2106: (63) *(u32 *)(r7 +29796) = r0 2107: (63) *(u32 *)(r7 +29800) = r0 2108: (63) *(u32 *)(r7 +29804) = r0 2109: (63) *(u32 *)(r7 +29808) = r0 2110: (63) *(u32 *)(r7 +29812) = r0 // overwrite scalar with dummy pointer; xored with random 'secret' value // of 943576462 before store ... 2111: (b4) w11 = 943576462 2112: (af) r11 ^= r7 2113: (7b) *(u64 *)(r10 -16) = r11 2114: (79) r11 = *(u64 *)(r10 -16) 2115: (b4) w2 = 943576462 2116: (af) r2 ^= r11 // ... and restored with the same 'secret' value with the help of AX reg. 2117: (71) r3 = *(u8 *)(r2 +0) [...] While the above would not prevent speculation, it would make data leakage infeasible by directing it to random locations. In order to be effective and prevent type confusion under speculation, such random secret would have to be regenerated for each store. The additional complexity involved for a tracking mechanism that prevents jumps such that restoring spilled pointers would not get corrupted is not worth the gain for unprivileged. Hence, the fix in here eventually opted for emitting a non-public BPF_ST | BPF_NOSPEC instruction which the x86 JIT translates into a lfence opcode. Inserting the latter in between the store and load instruction is one of the mitigations options [1]. The x86 instruction manual notes: [...] An LFENCE that follows an instruction that stores to memory might complete before the data being stored have become globally visible. [...] The latter meaning that the preceding store instruction finished execution and the store is at minimum guaranteed to be in the CPU's store queue, but it's not guaranteed to be in that CPU's L1 cache at that point (globally visible). The latter would only be guaranteed via sfence. So the load which is guaranteed to execute after the lfence for that local CPU would have to rely on store-to-load forwarding. [2], in section 2.3 on store buffers says: [...] For every store operation that is added to the ROB, an entry is allocated in the store buffer. This entry requires both the virtual and physical address of the target. Only if there is no free entry in the store buffer, the frontend stalls until there is an empty slot available in the store buffer again. Otherwise, the CPU can immediately continue adding subsequent instructions to the ROB and execute them out of order. On Intel CPUs, the store buffer has up to 56 entries. [...] One small upside on the fix is that it lifts constraints from af86ca4e3088 where the sanitize_stack_off relative to r10 must be the same when coming from different paths. The BPF_ST | BPF_NOSPEC gets emitted after a BPF_STX or BPF_ST instruction. This happens either when we store a pointer or data value to the BPF stack for the first time, or upon later pointer spills. The former needs to be enforced since otherwise stale stack data could be leaked under speculation as outlined earlier. For non-x86 JITs the BPF_ST | BPF_NOSPEC mapping is currently optimized away, but others could emit a speculation barrier as well if necessary. For real-world unprivileged programs e.g. generated by LLVM, pointer spill/fill is only generated upon register pressure and LLVM only tries to do that for pointers which are not used often. The program main impact will be the initial BPF_ST | BPF_NOSPEC sanitation for the STACK_INVALID case when the first write to a stack slot occurs e.g. upon map lookup. In future we might refine ways to mitigate the latter cost. [0] https://arxiv.org/pdf/1902.05178.pdf [1] https://msrc-blog.microsoft.com/2018/05/21/analysis-and-mitigation-of-speculative-store-bypass-cve-2018-3639/ [2] https://arxiv.org/pdf/1905.05725.pdf Fixes: af86ca4e3088 ("bpf: Prevent memory disambiguation attack") Fixes: f7cf25b2026d ("bpf: track spill/fill of constants") Co-developed-by: Piotr Krysiuk <piotras@gmail.com> Co-developed-by: Benedict Schlueter <benedict.schlueter@rub.de> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Piotr Krysiuk <piotras@gmail.com> Signed-off-by: Benedict Schlueter <benedict.schlueter@rub.de> Acked-by: Alexei Starovoitov <ast@kernel.org>
| | * | | | | bpf: Introduce BPF nospec instruction for mitigating Spectre v4Daniel Borkmann2021-07-2914-8/+102
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In case of JITs, each of the JIT backends compiles the BPF nospec instruction /either/ to a machine instruction which emits a speculation barrier /or/ to /no/ machine instruction in case the underlying architecture is not affected by Speculative Store Bypass or has different mitigations in place already. This covers both x86 and (implicitly) arm64: In case of x86, we use 'lfence' instruction for mitigation. In case of arm64, we rely on the firmware mitigation as controlled via the ssbd kernel parameter. Whenever the mitigation is enabled, it works for all of the kernel code with no need to provide any additional instructions here (hence only comment in arm64 JIT). Other archs can follow as needed. The BPF nospec instruction is specifically targeting Spectre v4 since i) we don't use a serialization barrier for the Spectre v1 case, and ii) mitigation instructions for v1 and v4 might be different on some archs. The BPF nospec is required for a future commit, where the BPF verifier does annotate intermediate BPF programs with speculation barriers. Co-developed-by: Piotr Krysiuk <piotras@gmail.com> Co-developed-by: Benedict Schlueter <benedict.schlueter@rub.de> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Piotr Krysiuk <piotras@gmail.com> Signed-off-by: Benedict Schlueter <benedict.schlueter@rub.de> Acked-by: Alexei Starovoitov <ast@kernel.org>
| | * | | | | Merge branch 'sockmap fixes picked up by stress tests'Andrii Nakryiko2021-07-272-30/+63
| | |\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | John Fastabend says: ==================== Running stress tests with recent patch to remove an extra lock in sockmap resulted in a couple new issues popping up. It seems only one of them is actually related to the patch: 799aa7f98d53 ("skmsg: Avoid lock_sock() in sk_psock_backlog()") The other two issues had existed long before, but I guess the timing with the serialization we had before was too tight to get any of our tests or deployments to hit it. With attached series stress testing sockmap+TCP with workloads that create lots of short-lived connections no more splats like below were seen on upstream bpf branch. [224913.935822] WARNING: CPU: 3 PID: 32100 at net/core/stream.c:208 sk_stream_kill_queues+0x212/0x220 [224913.935841] Modules linked in: fuse overlay bpf_preload x86_pkg_temp_thermal intel_uncore wmi_bmof squashfs sch_fq_codel efivarfs ip_tables x_tables uas xhci_pci ixgbe mdio xfrm_algo xhci_hcd wmi [224913.935897] CPU: 3 PID: 32100 Comm: fgs-bench Tainted: G I 5.14.0-rc1alu+ #181 [224913.935908] Hardware name: Dell Inc. Precision 5820 Tower/002KVM, BIOS 1.9.2 01/24/2019 [224913.935914] RIP: 0010:sk_stream_kill_queues+0x212/0x220 [224913.935923] Code: 8b 83 20 02 00 00 85 c0 75 20 5b 5d 41 5c 41 5d 41 5e 41 5f c3 48 89 df e8 2b 11 fe ff eb c3 0f 0b e9 7c ff ff ff 0f 0b eb ce <0f> 0b 5b 5d 41 5c 41 5d 41 5e 41 5f c3 90 0f 1f 44 00 00 41 57 41 [224913.935932] RSP: 0018:ffff88816271fd38 EFLAGS: 00010206 [224913.935941] RAX: 0000000000000ae8 RBX: ffff88815acd5240 RCX: dffffc0000000000 [224913.935948] RDX: 0000000000000003 RSI: 0000000000000ae8 RDI: ffff88815acd5460 [224913.935954] RBP: ffff88815acd5460 R08: ffffffff955c0ae8 R09: fffffbfff2e6f543 [224913.935961] R10: ffffffff9737aa17 R11: fffffbfff2e6f542 R12: ffff88815acd5390 [224913.935967] R13: ffff88815acd5480 R14: ffffffff98d0c080 R15: ffffffff96267500 [224913.935974] FS: 00007f86e6bd1700(0000) GS:ffff888451cc0000(0000) knlGS:0000000000000000 [224913.935981] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [224913.935988] CR2: 000000c0008eb000 CR3: 00000001020e0005 CR4: 00000000003706e0 [224913.935994] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [224913.936000] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [224913.936007] Call Trace: [224913.936016] inet_csk_destroy_sock+0xba/0x1f0 [224913.936033] __tcp_close+0x620/0x790 [224913.936047] tcp_close+0x20/0x80 [224913.936056] inet_release+0x8f/0xf0 [224913.936070] __sock_release+0x72/0x120 v3: make sock_drop inline in skmsg.h v2: init skb to null and fix a space/tab issue. Added Jakub's acks. ==================== Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
| | | * | | | | bpf, sockmap: Fix memleak on ingress msg enqueueJohn Fastabend2021-07-272-25/+35
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If backlog handler is running during a tear down operation we may enqueue data on the ingress msg queue while tear down is trying to free it. sk_psock_backlog() sk_psock_handle_skb() skb_psock_skb_ingress() sk_psock_skb_ingress_enqueue() sk_psock_queue_msg(psock,msg) spin_lock(ingress_lock) sk_psock_zap_ingress() _sk_psock_purge_ingerss_msg() _sk_psock_purge_ingress_msg() -- free ingress_msg list -- spin_unlock(ingress_lock) spin_lock(ingress_lock) list_add_tail(msg,ingress_msg) <- entry on list with no one left to free it. spin_unlock(ingress_lock) To fix we only enqueue from backlog if the ENABLED bit is set. The tear down logic clears the bit with ingress_lock set so we wont enqueue the msg in the last step. Fixes: 799aa7f98d53 ("skmsg: Avoid lock_sock() in sk_psock_backlog()") Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Jakub Sitnicki <jakub@cloudflare.com> Acked-by: Martin KaFai Lau <kafai@fb.com> Link: https://lore.kernel.org/bpf/20210727160500.1713554-4-john.fastabend@gmail.com
| | | * | | | | bpf, sockmap: On cleanup we additionally need to remove cached skbJohn Fastabend2021-07-271-6/+29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Its possible if a socket is closed and the receive thread is under memory pressure it may have cached a skb. We need to ensure these skbs are free'd along with the normal ingress_skb queue. Before 799aa7f98d53 ("skmsg: Avoid lock_sock() in sk_psock_backlog()") tear down and backlog processing both had sock_lock for the common case of socket close or unhash. So it was not possible to have both running in parrallel so all we would need is the kfree in those kernels. But, latest kernels include the commit 799aa7f98d5e and this requires a bit more work. Without the ingress_lock guarding reading/writing the state->skb case its possible the tear down could run before the state update causing it to leak memory or worse when the backlog reads the state it could potentially run interleaved with the tear down and we might end up free'ing the state->skb from tear down side but already have the reference from backlog side. To resolve such races we wrap accesses in ingress_lock on both sides serializing tear down and backlog case. In both cases this only happens after an EAGAIN error case so having an extra lock in place is likely fine. The normal path will skip the locks. Note, we check state->skb before grabbing lock. This works because we can only enqueue with the mutex we hold already. Avoiding a race on adding state->skb after the check. And if tear down path is running that is also fine if the tear down path then removes state->skb we will simply set skb=NULL and the subsequent goto is skipped. This slight complication avoids locking in normal case. With this fix we no longer see this warning splat from tcp side on socket close when we hit the above case with redirect to ingress self. [224913.935822] WARNING: CPU: 3 PID: 32100 at net/core/stream.c:208 sk_stream_kill_queues+0x212/0x220 [224913.935841] Modules linked in: fuse overlay bpf_preload x86_pkg_temp_thermal intel_uncore wmi_bmof squashfs sch_fq_codel efivarfs ip_tables x_tables uas xhci_pci ixgbe mdio xfrm_algo xhci_hcd wmi [224913.935897] CPU: 3 PID: 32100 Comm: fgs-bench Tainted: G I 5.14.0-rc1alu+ #181 [224913.935908] Hardware name: Dell Inc. Precision 5820 Tower/002KVM, BIOS 1.9.2 01/24/2019 [224913.935914] RIP: 0010:sk_stream_kill_queues+0x212/0x220 [224913.935923] Code: 8b 83 20 02 00 00 85 c0 75 20 5b 5d 41 5c 41 5d 41 5e 41 5f c3 48 89 df e8 2b 11 fe ff eb c3 0f 0b e9 7c ff ff ff 0f 0b eb ce <0f> 0b 5b 5d 41 5c 41 5d 41 5e 41 5f c3 90 0f 1f 44 00 00 41 57 41 [224913.935932] RSP: 0018:ffff88816271fd38 EFLAGS: 00010206 [224913.935941] RAX: 0000000000000ae8 RBX: ffff88815acd5240 RCX: dffffc0000000000 [224913.935948] RDX: 0000000000000003 RSI: 0000000000000ae8 RDI: ffff88815acd5460 [224913.935954] RBP: ffff88815acd5460 R08: ffffffff955c0ae8 R09: fffffbfff2e6f543 [224913.935961] R10: ffffffff9737aa17 R11: fffffbfff2e6f542 R12: ffff88815acd5390 [224913.935967] R13: ffff88815acd5480 R14: ffffffff98d0c080 R15: ffffffff96267500 [224913.935974] FS: 00007f86e6bd1700(0000) GS:ffff888451cc0000(0000) knlGS:0000000000000000 [224913.935981] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [224913.935988] CR2: 000000c0008eb000 CR3: 00000001020e0005 CR4: 00000000003706e0 [224913.935994] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [224913.936000] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [224913.936007] Call Trace: [224913.936016] inet_csk_destroy_sock+0xba/0x1f0 [224913.936033] __tcp_close+0x620/0x790 [224913.936047] tcp_close+0x20/0x80 [224913.936056] inet_release+0x8f/0xf0 [224913.936070] __sock_release+0x72/0x120 [224913.936083] sock_close+0x14/0x20 Fixes: a136678c0bdbb ("bpf: sk_msg, zap ingress queue on psock down") Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Jakub Sitnicki <jakub@cloudflare.com> Acked-by: Martin KaFai Lau <kafai@fb.com> Link: https://lore.kernel.org/bpf/20210727160500.1713554-3-john.fastabend@gmail.com
| | | * | | | | bpf, sockmap: Zap ingress queues after stopping strparserJohn Fastabend2021-07-271-2/+2
| | |/ / / / / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We don't want strparser to run and pass skbs into skmsg handlers when the psock is null. We just sk_drop them in this case. When removing a live socket from map it means extra drops that we do not need to incur. Move the zap below strparser close to avoid this condition. This way we stop the stream parser first stopping it from processing packets and then delete the psock. Fixes: a136678c0bdbb ("bpf: sk_msg, zap ingress queue on psock down") Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Jakub Sitnicki <jakub@cloudflare.com> Acked-by: Martin KaFai Lau <kafai@fb.com> Link: https://lore.kernel.org/bpf/20210727160500.1713554-2-john.fastabend@gmail.com
| | * | | | | bpf: Fix OOB read when printing XDP link fdinfoLorenz Bauer2021-07-201-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We got the following UBSAN report on one of our testing machines: ================================================================================ UBSAN: array-index-out-of-bounds in kernel/bpf/syscall.c:2389:24 index 6 is out of range for type 'char *[6]' CPU: 43 PID: 930921 Comm: systemd-coredum Tainted: G O 5.10.48-cloudflare-kasan-2021.7.0 #1 Hardware name: <snip> Call Trace: dump_stack+0x7d/0xa3 ubsan_epilogue+0x5/0x40 __ubsan_handle_out_of_bounds.cold+0x43/0x48 ? seq_printf+0x17d/0x250 bpf_link_show_fdinfo+0x329/0x380 ? bpf_map_value_size+0xe0/0xe0 ? put_files_struct+0x20/0x2d0 ? __kasan_kmalloc.constprop.0+0xc2/0xd0 seq_show+0x3f7/0x540 seq_read_iter+0x3f8/0x1040 seq_read+0x329/0x500 ? seq_read_iter+0x1040/0x1040 ? __fsnotify_parent+0x80/0x820 ? __fsnotify_update_child_dentry_flags+0x380/0x380 vfs_read+0x123/0x460 ksys_read+0xed/0x1c0 ? __x64_sys_pwrite64+0x1f0/0x1f0 do_syscall_64+0x33/0x40 entry_SYSCALL_64_after_hwframe+0x44/0xa9 <snip> ================================================================================ ================================================================================ UBSAN: object-size-mismatch in kernel/bpf/syscall.c:2384:2 From the report, we can infer that some array access in bpf_link_show_fdinfo at index 6 is out of bounds. The obvious candidate is bpf_link_type_strs[BPF_LINK_TYPE_XDP] with BPF_LINK_TYPE_XDP == 6. It turns out that BPF_LINK_TYPE_XDP is missing from bpf_types.h and therefore doesn't have an entry in bpf_link_type_strs: pos: 0 flags: 02000000 mnt_id: 13 link_type: (null) link_id: 4 prog_tag: bcf7977d3b93787c prog_id: 4 ifindex: 1 Fixes: aa8d3a716b59 ("bpf, xdp: Add bpf_link-based XDP attachment API") Signed-off-by: Lorenz Bauer <lmb@cloudflare.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20210719085134.43325-2-lmb@cloudflare.com
| | * | | | | bpf, selftests: Add test cases for pointer alu from multiple pathsDaniel Borkmann2021-07-161-0/+229
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add several test cases for checking update_alu_sanitation_state() under multiple paths: # ./test_verifier [...] #1061/u map access: known scalar += value_ptr unknown vs const OK #1061/p map access: known scalar += value_ptr unknown vs const OK #1062/u map access: known scalar += value_ptr const vs unknown OK #1062/p map access: known scalar += value_ptr const vs unknown OK #1063/u map access: known scalar += value_ptr const vs const (ne) OK #1063/p map access: known scalar += value_ptr const vs const (ne) OK #1064/u map access: known scalar += value_ptr const vs const (eq) OK #1064/p map access: known scalar += value_ptr const vs const (eq) OK #1065/u map access: known scalar += value_ptr unknown vs unknown (eq) OK #1065/p map access: known scalar += value_ptr unknown vs unknown (eq) OK #1066/u map access: known scalar += value_ptr unknown vs unknown (lt) OK #1066/p map access: known scalar += value_ptr unknown vs unknown (lt) OK #1067/u map access: known scalar += value_ptr unknown vs unknown (gt) OK #1067/p map access: known scalar += value_ptr unknown vs unknown (gt) OK [...] Summary: 1762 PASSED, 0 SKIPPED, 0 FAILED Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org>
| | * | | | | bpf: Fix pointer arithmetic mask tightening under state pruningDaniel Borkmann2021-07-162-10/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In 7fedb63a8307 ("bpf: Tighten speculative pointer arithmetic mask") we narrowed the offset mask for unprivileged pointer arithmetic in order to mitigate a corner case where in the speculative domain it is possible to advance, for example, the map value pointer by up to value_size-1 out-of- bounds in order to leak kernel memory via side-channel to user space. The verifier's state pruning for scalars leaves one corner case open where in the first verification path R_x holds an unknown scalar with an aux->alu_limit of e.g. 7, and in a second verification path that same register R_x, here denoted as R_x', holds an unknown scalar which has tighter bounds and would thus satisfy range_within(R_x, R_x') as well as tnum_in(R_x, R_x') for state pruning, yielding an aux->alu_limit of 3: Given the second path fits the register constraints for pruning, the final generated mask from aux->alu_limit will remain at 7. While technically not wrong for the non-speculative domain, it would however be possible to craft similar cases where the mask would be too wide as in 7fedb63a8307. One way to fix it is to detect the presence of unknown scalar map pointer arithmetic and force a deeper search on unknown scalars to ensure that we do not run into a masking mismatch. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org>
| | * | | | | bpf: Remove superfluous aux sanitation on subprog rejectionDaniel Borkmann2021-07-161-34/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Follow-up to fe9a5ca7e370 ("bpf: Do not mark insn as seen under speculative path verification"). The sanitize_insn_aux_data() helper does not serve a particular purpose in today's code. The original intention for the helper was that if function-by-function verification fails, a given program would be cleared from temporary insn_aux_data[], and then its verification would be re-attempted in the context of the main program a second time. However, a failure in do_check_subprogs() will skip do_check_main() and propagate the error to the user instead, thus such situation can never occur. Given its interaction is not compatible to the Spectre v1 mitigation (due to comparing aux->seen with env->pass_cnt), just remove sanitize_insn_aux_data() to avoid future bugs in this area. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org>
| * | | | | | sis900: Fix missing pci_disable_device() in probe and removeWang Hai2021-07-281-5/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Replace pci_enable_device() with pcim_enable_device(), pci_disable_device() and pci_release_regions() will be called in release automatically. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Wang Hai <wanghai38@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | | | | | net: let flow have same hash in two directionszhang kai2021-07-281-9/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | using same source and destination ip/port for flow hash calculation within the two directions. Signed-off-by: zhang kai <zhangkaiheb@126.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | | | | | nfc: nfcsim: fix use after free during module unloadKrzysztof Kozlowski2021-07-281-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There is a use after free memory corruption during module exit: - nfcsim_exit() - nfcsim_device_free(dev0) - nfc_digital_unregister_device() This iterates over command queue and frees all commands, - dev->up = false - nfcsim_link_shutdown() - nfcsim_link_recv_wake() This wakes the sleeping thread nfcsim_link_recv_skb(). - nfcsim_link_recv_skb() Wake from wait_event_interruptible_timeout(), call directly the deb->cb callback even though (dev->up == false), - digital_send_cmd_complete() Dereference of "struct digital_cmd" cmd which was freed earlier by nfc_digital_unregister_device(). This causes memory corruption shortly after (with unrelated stack trace): nfc nfc0: NFC: nfcsim_recv_wq: Device is down llcp: nfc_llcp_recv: err -19 nfc nfc1: NFC: nfcsim_recv_wq: Device is down BUG: unable to handle page fault for address: ffffffffffffffed Call Trace: fsnotify+0x54b/0x5c0 __fsnotify_parent+0x1fe/0x300 ? vfs_write+0x27c/0x390 vfs_write+0x27c/0x390 ksys_write+0x63/0xe0 do_syscall_64+0x3b/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae KASAN report: BUG: KASAN: use-after-free in digital_send_cmd_complete+0x16/0x50 Write of size 8 at addr ffff88800a05f720 by task kworker/0:2/71 Workqueue: events nfcsim_recv_wq [nfcsim] Call Trace:  dump_stack_lvl+0x45/0x59  print_address_description.constprop.0+0x21/0x140  ? digital_send_cmd_complete+0x16/0x50  ? digital_send_cmd_complete+0x16/0x50  kasan_report.cold+0x7f/0x11b  ? digital_send_cmd_complete+0x16/0x50  ? digital_dep_link_down+0x60/0x60  digital_send_cmd_complete+0x16/0x50  nfcsim_recv_wq+0x38f/0x3d5 [nfcsim]  ? nfcsim_in_send_cmd+0x4a/0x4a [nfcsim]  ? lock_is_held_type+0x98/0x110  ? finish_wait+0x110/0x110  ? rcu_read_lock_sched_held+0x9c/0xd0  ? rcu_read_lock_bh_held+0xb0/0xb0  ? lockdep_hardirqs_on_prepare+0x12e/0x1f0 This flow of calling digital_send_cmd_complete() callback on driver exit is specific to nfcsim which implements reading and sending work queues. Since the NFC digital device was unregistered, the callback should not be called. Fixes: 204bddcb508f ("NFC: nfcsim: Make use of the Digital layer") Cc: <stable@vger.kernel.org> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com> Signed-off-by: David S. Miller <davem@davemloft.net>