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* Merge tag 'for-5.5-rc8-tag' of ↵Linus Torvalds2020-01-252-9/+29
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs fix from David Sterba: "Here's a last minute fix for a regression introduced in this development cycle. There's a small chance of a silent corruption when device replace and NOCOW data writes happen at the same time in one block group. Metadata or COW data writes are unaffected. The extra fixup patch is there to silence an unnecessary warning" * tag 'for-5.5-rc8-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: btrfs: dev-replace: remove warning for unknown return codes when finished btrfs: scrub: Require mandatory block group RO for dev-replace
| * btrfs: dev-replace: remove warning for unknown return codes when finishedDavid Sterba2020-01-251-4/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The fstests btrfs/011 triggered a warning at the end of device replace, [ 1891.998975] BTRFS warning (device vdd): failed setting block group ro: -28 [ 1892.038338] BTRFS error (device vdd): btrfs_scrub_dev(/dev/vdd, 1, /dev/vdb) failed -28 [ 1892.059993] ------------[ cut here ]------------ [ 1892.063032] WARNING: CPU: 2 PID: 2244 at fs/btrfs/dev-replace.c:506 btrfs_dev_replace_start.cold+0xf9/0x140 [btrfs] [ 1892.074346] CPU: 2 PID: 2244 Comm: btrfs Not tainted 5.5.0-rc7-default+ #942 [ 1892.079956] RIP: 0010:btrfs_dev_replace_start.cold+0xf9/0x140 [btrfs] [ 1892.096576] RSP: 0018:ffffbb58c7b3fd10 EFLAGS: 00010286 [ 1892.098311] RAX: 00000000ffffffe4 RBX: 0000000000000001 RCX: 8888888888888889 [ 1892.100342] RDX: 0000000000000001 RSI: ffff9e889645f5d8 RDI: ffffffff92821080 [ 1892.102291] RBP: ffff9e889645c000 R08: 000001b8878fe1f6 R09: 0000000000000000 [ 1892.104239] R10: ffffbb58c7b3fd08 R11: 0000000000000000 R12: ffff9e88a0017000 [ 1892.106434] R13: ffff9e889645f608 R14: ffff9e88794e1000 R15: ffff9e88a07b5200 [ 1892.108642] FS: 00007fcaed3f18c0(0000) GS:ffff9e88bda00000(0000) knlGS:0000000000000000 [ 1892.111558] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1892.113492] CR2: 00007f52509ff420 CR3: 00000000603dd002 CR4: 0000000000160ee0 [ 1892.115814] Call Trace: [ 1892.116896] btrfs_dev_replace_by_ioctl+0x35/0x60 [btrfs] [ 1892.118962] btrfs_ioctl+0x1d62/0x2550 [btrfs] caused by the previous patch ("btrfs: scrub: Require mandatory block group RO for dev-replace"). Hitting ENOSPC is possible and could happen when the block group is set read-only, preventing NOCOW writes to the area that's being accessed by dev-replace. This has happend with scratch devices of size 12G but not with 5G and 20G, so this is depends on timing and other activity on the filesystem. The whole replace operation is restartable, the space state should be examined by the user in any case. The error code is propagated back to the ioctl caller so the kernel warning is causing false alerts. Signed-off-by: David Sterba <dsterba@suse.com>
| * btrfs: scrub: Require mandatory block group RO for dev-replaceQu Wenruo2020-01-241-5/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [BUG] For dev-replace test cases with fsstress, like btrfs/06[45] btrfs/071, looped runs can lead to random failure, where scrub finds csum error. The possibility is not high, around 1/20 to 1/100, but it's causing data corruption. The bug is observable after commit b12de52896c0 ("btrfs: scrub: Don't check free space before marking a block group RO") [CAUSE] Dev-replace has two source of writes: - Write duplication All writes to source device will also be duplicated to target device. Content: Not yet persisted data/meta - Scrub copy Dev-replace reused scrub code to iterate through existing extents, and copy the verified data to target device. Content: Previously persisted data and metadata The difference in contents makes the following race possible: Regular Writer | Dev-replace ----------------------------------------------------------------- ^ | | Preallocate one data extent | | at bytenr X, len 1M | v | ^ Commit transaction | | Now extent [X, X+1M) is in | v commit root | ================== Dev replace starts ========================= | ^ | | Scrub extent [X, X+1M) | | Read [X, X+1M) | | (The content are mostly garbage | | since it's preallocated) ^ | v | Write back happens for | | extent [X, X+512K) | | New data writes to both | | source and target dev. | v | | ^ | | Scrub writes back extent [X, X+1M) | | to target device. | | This will over write the new data in | | [X, X+512K) | v This race can only happen for nocow writes. Thus metadata and data cow writes are safe, as COW will never overwrite extents of previous transaction (in commit root). This behavior can be confirmed by disabling all fallocate related calls in fsstress (*), then all related tests can pass a 2000 run loop. *: FSSTRESS_AVOID="-f fallocate=0 -f allocsp=0 -f zero=0 -f insert=0 \ -f collapse=0 -f punch=0 -f resvsp=0" I didn't expect resvsp ioctl will fallback to fallocate in VFS... [FIX] Make dev-replace to require mandatory block group RO, and wait for current nocow writes before calling scrub_chunk(). This patch will mostly revert commit 76a8efa171bf ("btrfs: Continue replace when set_block_ro failed") for dev-replace path. The side effect is, dev-replace can be more strict on avaialble space, but definitely worth to avoid data corruption. Reported-by: Filipe Manana <fdmanana@suse.com> Fixes: 76a8efa171bf ("btrfs: Continue replace when set_block_ro failed") Fixes: b12de52896c0 ("btrfs: scrub: Don't check free space before marking a block group RO") Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* | Merge tag 'ceph-for-5.5-rc8' of https://github.com/ceph/ceph-clientLinus Torvalds2020-01-231-2/+6
|\ \ | | | | | | | | | | | | | | | | | | | | | Pull ceph fix from Ilya Dryomov: "A fix for a potential use-after-free from Jeff, marked for stable" * tag 'ceph-for-5.5-rc8' of https://github.com/ceph/ceph-client: ceph: hold extra reference to r_parent over life of request
| * | ceph: hold extra reference to r_parent over life of requestJeff Layton2020-01-211-2/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, we just assume that it will stick around by virtue of the submitter's reference, but later patches will allow the syscall to return early and we can't rely on that reference at that point. While I'm not aware of any reports of it, Xiubo pointed out that this may fix a use-after-free. If the wait for a reply times out or is canceled via signal, and then the reply comes in after the syscall returns, the client can end up trying to access r_parent without a reference. Take an extra reference to the inode when setting r_parent and release it when releasing the request. Cc: stable@vger.kernel.org Signed-off-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: "Yan, Zheng" <zyan@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
* | | readdir: make user_access_begin() use the real access rangeLinus Torvalds2020-01-231-38/+35
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In commit 9f79b78ef744 ("Convert filldir[64]() from __put_user() to unsafe_put_user()") I changed filldir to not do individual __put_user() accesses, but instead use unsafe_put_user() surrounded by the proper user_access_begin/end() pair. That make them enormously faster on modern x86, where the STAC/CLAC games make individual user accesses fairly heavy-weight. However, the user_access_begin() range was not really the exact right one, since filldir() has the unfortunate problem that it needs to not only fill out the new directory entry, it also needs to fix up the previous one to contain the proper file offset. It's unfortunate, but the "d_off" field in "struct dirent" is _not_ the file offset of the directory entry itself - it's the offset of the next one. So we end up backfilling the offset in the previous entry as we walk along. But since x86 didn't really care about the exact range, and used to be the only architecture that did anything fancy in user_access_begin() to begin with, the filldir[64]() changes did something lazy, and even commented on it: /* * Note! This range-checks 'previous' (which may be NULL). * The real range was checked in getdents */ if (!user_access_begin(dirent, sizeof(*dirent))) goto efault; and it all worked fine. But now 32-bit ppc is starting to also implement user_access_begin(), and the fact that we faked the range to only be the (possibly not even valid) previous directory entry becomes a problem, because ppc32 will actually be using the range that is passed in for more than just "check that it's user space". This is a complete rewrite of Christophe's original patch. By saving off the record length of the previous entry instead of a pointer to it in the filldir data structures, we can simplify the range check and the writing of the previous entry d_off field. No need for any conditionals in the user accesses themselves, although we retain the conditional EINTR checking for the "was this the first directory entry" signal handling latency logic. Fixes: 9f79b78ef744 ("Convert filldir[64]() from __put_user() to unsafe_put_user()") Link: https://lore.kernel.org/lkml/a02d3426f93f7eb04960a4d9140902d278cab0bb.1579697910.git.christophe.leroy@c-s.fr/ Link: https://lore.kernel.org/lkml/408c90c4068b00ea8f1c41cca45b84ec23d4946b.1579783936.git.christophe.leroy@c-s.fr/ Reported-and-tested-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | readdir: be more conservative with directory entry namesLinus Torvalds2020-01-231-1/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 8a23eb804ca4 ("Make filldir[64]() verify the directory entry filename is valid") added some minimal validity checks on the directory entries passed to filldir[64](). But they really were pretty minimal. This fleshes out at least the name length check: we used to disallow zero-length names, but really, negative lengths or oevr-long names aren't ok either. Both could happen if there is some filesystem corruption going on. Now, most filesystems tend to use just an "unsigned char" or similar for the length of a directory entry name, so even with a corrupt filesystem you should never see anything odd like that. But since we then use the name length to create the directory entry record length, let's make sure it actually is half-way sensible. Note how POSIX states that the size of a path component is limited by NAME_MAX, but we actually use PATH_MAX for the check here. That's because while NAME_MAX is generally the correct maximum name length (it's 255, for the same old "name length is usually just a byte on disk"), there's nothing in the VFS layer that really cares. So the real limitation at a VFS layer is the total pathname length you can pass as a filename: PATH_MAX. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | Merge tag 'io_uring-5.5-2020-01-22' of git://git.kernel.dk/linux-blockLinus Torvalds2020-01-221-1/+3
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull io_uring fix from Jens Axboe: "This was supposed to have gone in last week, but due to a brain fart on my part, I forgot that we made this struct addition in the 5.5 cycle. So here it is for 5.5, to prevent having a 32 vs 64-bit compatability issue with the files_update command" * tag 'io_uring-5.5-2020-01-22' of git://git.kernel.dk/linux-block: io_uring: fix compat for IORING_REGISTER_FILES_UPDATE
| * | | io_uring: fix compat for IORING_REGISTER_FILES_UPDATEEugene Syromiatnikov2020-01-211-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | fds field of struct io_uring_files_update is problematic with regards to compat user space, as pointer size is different in 32-bit, 32-on-64-bit, and 64-bit user space. In order to avoid custom handling of compat in the syscall implementation, make fds __u64 and use u64_to_user_ptr in order to retrieve it. Also, align the field naturally and check that no garbage is passed there. Fixes: c3a31e605620c279 ("io_uring: add support for IORING_REGISTER_FILES_UPDATE") Signed-off-by: Eugene Syromiatnikov <esyr@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
* | | | Merge tag 'fixes_for_v5.5-rc8' of ↵Linus Torvalds2020-01-201-2/+6
|\ \ \ \ | |_|/ / |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs Pull reiserfs fix from Jan Kara: "A fixup of a recently merged reiserfs fix which has caused problem when xattrs were not compiled in" * tag 'fixes_for_v5.5-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs: reiserfs: fix handling of -EOPNOTSUPP in reiserfs_for_each_xattr
| * | | reiserfs: fix handling of -EOPNOTSUPP in reiserfs_for_each_xattrJeff Mahoney2020-01-161-2/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 60e4cf67a58 (reiserfs: fix extended attributes on the root directory) introduced a regression open_xa_root started returning -EOPNOTSUPP but it was not handled properly in reiserfs_for_each_xattr. When the reiserfs module is built without CONFIG_REISERFS_FS_XATTR, deleting an inode would result in a warning and chowning an inode would also result in a warning and then fail to complete. With CONFIG_REISERFS_FS_XATTR enabled, the xattr root would always be present for read-write operations. This commit handles -EOPNOSUPP in the same way -ENODATA is handled. Fixes: 60e4cf67a582 ("reiserfs: fix extended attributes on the root directory") CC: stable@vger.kernel.org # Commit 60e4cf67a58 was picked up by stable Link: https://lore.kernel.org/r/20200115180059.6935-1-jeffm@suse.com Reported-by: Michael Brunnbauer <brunni@netestate.de> Signed-off-by: Jeff Mahoney <jeffm@suse.com> Signed-off-by: Jan Kara <jack@suse.cz>
* | | | Merge tag 'io_uring-5.5-2020-01-16' of git://git.kernel.dk/linux-blockLinus Torvalds2020-01-172-28/+56
|\ \ \ \ | | |/ / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull io_uring fixes form Jens Axboe: - Ensure ->result is always set when IO is retried (Bijan) - In conjunction with the above, fix a regression in polled IO issue when retried (me/Bijan) - Don't setup async context for read/write fixed, otherwise we may wrongly map the iovec on retry (me) - Cancel io-wq work if we fail getting mm reference (me) - Ensure dependent work is always initialized correctly (me) - Only allow original task to submit IO, don't allow it from a passed ring fd (me) * tag 'io_uring-5.5-2020-01-16' of git://git.kernel.dk/linux-block: io_uring: only allow submit from owning task io_uring: ensure workqueue offload grabs ring mutex for poll list io_uring: clear req->result always before issuing a read/write request io_uring: be consistent in assigning next work from handler io-wq: cancel work if we fail getting a mm reference io_uring: don't setup async context for read/write fixed
| * | | io_uring: only allow submit from owning taskJens Axboe2020-01-171-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If the credentials or the mm doesn't match, don't allow the task to submit anything on behalf of this ring. The task that owns the ring can pass the file descriptor to another task, but we don't want to allow that task to submit an SQE that then assumes the ring mm and creds if it needs to go async. Cc: stable@vger.kernel.org Suggested-by: Stefan Metzmacher <metze@samba.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | io_uring: ensure workqueue offload grabs ring mutex for poll listJens Axboe2020-01-161-0/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A previous commit moved the locking for the async sqthread, but didn't take into account that the io-wq workers still need it. We can't use req->in_async for this anymore as both the sqthread and io-wq workers set it, gate the need for locking on io_wq_current_is_worker() instead. Fixes: 8a4955ff1cca ("io_uring: sqthread should grab ctx->uring_lock for submissions") Reported-by: Bijan Mottahedeh <bijan.mottahedeh@oracle.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | io_uring: clear req->result always before issuing a read/write requestBijan Mottahedeh2020-01-161-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | req->result is cleared when io_issue_sqe() calls io_read/write_pre() routines. Those routines however are not called when the sqe argument is NULL, which is the case when io_issue_sqe() is called from io_wq_submit_work(). io_issue_sqe() may then examine a stale result if a polled request had previously failed with -EAGAIN: if (ctx->flags & IORING_SETUP_IOPOLL) { if (req->result == -EAGAIN) return -EAGAIN; io_iopoll_req_issued(req); } and in turn cause a subsequently completed request to be re-issued in io_wq_submit_work(). Signed-off-by: Bijan Mottahedeh <bijan.mottahedeh@oracle.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | io_uring: be consistent in assigning next work from handlerJens Axboe2020-01-151-24/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If we pass back dependent work in case of links, we need to always ensure that we call the link setup and work prep handler. If not, we might be missing some setup for the next work item. Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | io-wq: cancel work if we fail getting a mm referenceJens Axboe2020-01-151-4/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | If we require mm and user context, mark the request for cancellation if we fail to acquire the desired mm. Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | io_uring: don't setup async context for read/write fixedJens Axboe2020-01-141-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We don't need it, and if we have it, then the retry handler will attempt to copy the non-existent iovec with the inline iovec, with a segment count that doesn't make sense. Fixes: f67676d160c6 ("io_uring: ensure async punted read/write requests copy iovec") Reported-by: Jonathan Lemon <jonathan.lemon@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
* | | | Merge tag 'for-5.5-rc6-tag' of ↵Linus Torvalds2020-01-176-46/+114
|\ \ \ \ | | |_|/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs fixes from David Sterba: "A few more fixes that have been in the works during last twp weeks. All have a user visible effect and are stable material: - scrub: properly update progress after calling cancel ioctl, calling 'resume' would start from the beginning otherwise - fix subvolume reference removal, after moving out of the original path the reference is not recognized and will lead to transaction abort - fix reloc root lifetime checks, could lead to crashes when there's subvolume cleaning running in parallel - fix memory leak when quotas get disabled in the middle of extent accounting - fix transaction abort in case of balance being started on degraded mount on eg. RAID1" * tag 'for-5.5-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: btrfs: check rw_devices, not num_devices for balance Btrfs: always copy scrub arguments back to user space btrfs: relocation: fix reloc_root lifespan and access btrfs: fix memory leak in qgroup accounting btrfs: do not delete mismatched root refs btrfs: fix invalid removal of root ref btrfs: rework arguments of btrfs_unlink_subvol
| * | | btrfs: check rw_devices, not num_devices for balanceJosef Bacik2020-01-171-1/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The fstest btrfs/154 reports [ 8675.381709] BTRFS: Transaction aborted (error -28) [ 8675.383302] WARNING: CPU: 1 PID: 31900 at fs/btrfs/block-group.c:2038 btrfs_create_pending_block_groups+0x1e0/0x1f0 [btrfs] [ 8675.390925] CPU: 1 PID: 31900 Comm: btrfs Not tainted 5.5.0-rc6-default+ #935 [ 8675.392780] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-59-gc9ba527-rebuilt.opensuse.org 04/01/2014 [ 8675.395452] RIP: 0010:btrfs_create_pending_block_groups+0x1e0/0x1f0 [btrfs] [ 8675.402672] RSP: 0018:ffffb2090888fb00 EFLAGS: 00010286 [ 8675.404413] RAX: 0000000000000000 RBX: ffff92026dfa91c8 RCX: 0000000000000001 [ 8675.406609] RDX: 0000000000000000 RSI: ffffffff8e100899 RDI: ffffffff8e100971 [ 8675.408775] RBP: ffff920247c61660 R08: 0000000000000000 R09: 0000000000000000 [ 8675.410978] R10: 0000000000000000 R11: 0000000000000000 R12: 00000000ffffffe4 [ 8675.412647] R13: ffff92026db74000 R14: ffff920247c616b8 R15: ffff92026dfbc000 [ 8675.413994] FS: 00007fd5e57248c0(0000) GS:ffff92027d800000(0000) knlGS:0000000000000000 [ 8675.416146] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 8675.417833] CR2: 0000564aa51682d8 CR3: 000000006dcbc004 CR4: 0000000000160ee0 [ 8675.419801] Call Trace: [ 8675.420742] btrfs_start_dirty_block_groups+0x355/0x480 [btrfs] [ 8675.422600] btrfs_commit_transaction+0xc8/0xaf0 [btrfs] [ 8675.424335] reset_balance_state+0x14a/0x190 [btrfs] [ 8675.425824] btrfs_balance.cold+0xe7/0x154 [btrfs] [ 8675.427313] ? kmem_cache_alloc_trace+0x235/0x2c0 [ 8675.428663] btrfs_ioctl_balance+0x298/0x350 [btrfs] [ 8675.430285] btrfs_ioctl+0x466/0x2550 [btrfs] [ 8675.431788] ? mem_cgroup_charge_statistics+0x51/0xf0 [ 8675.433487] ? mem_cgroup_commit_charge+0x56/0x400 [ 8675.435122] ? do_raw_spin_unlock+0x4b/0xc0 [ 8675.436618] ? _raw_spin_unlock+0x1f/0x30 [ 8675.438093] ? __handle_mm_fault+0x499/0x740 [ 8675.439619] ? do_vfs_ioctl+0x56e/0x770 [ 8675.441034] do_vfs_ioctl+0x56e/0x770 [ 8675.442411] ksys_ioctl+0x3a/0x70 [ 8675.443718] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 8675.445333] __x64_sys_ioctl+0x16/0x20 [ 8675.446705] do_syscall_64+0x50/0x210 [ 8675.448059] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 8675.479187] BTRFS: error (device vdb) in btrfs_create_pending_block_groups:2038: errno=-28 No space left We now use btrfs_can_overcommit() to see if we can flip a block group read only. Before this would fail because we weren't taking into account the usable un-allocated space for allocating chunks. With my patches we were allowed to do the balance, which is technically correct. The test is trying to start balance on degraded mount. So now we're trying to allocate a chunk and cannot because we want to allocate a RAID1 chunk, but there's only 1 device that's available for usage. This results in an ENOSPC. But we shouldn't even be making it this far, we don't have enough devices to restripe. The problem is we're using btrfs_num_devices(), that also includes missing devices. That's not actually what we want, we need to use rw_devices. The chunk_mutex is not needed here, rw_devices changes only in device add, remove or replace, all are excluded by EXCL_OP mechanism. Fixes: e4d8ec0f65b9 ("Btrfs: implement online profile changing") CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> [ add stacktrace, update changelog, drop chunk_mutex ] Signed-off-by: David Sterba <dsterba@suse.com>
| * | | Btrfs: always copy scrub arguments back to user spaceFilipe Manana2020-01-171-1/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If scrub returns an error we are not copying back the scrub arguments structure to user space. This prevents user space to know how much progress scrub has done if an error happened - this includes -ECANCELED which is returned when users ask for scrub to stop. A particular use case, which is used in btrfs-progs, is to resume scrub after it is canceled, in that case it relies on checking the progress from the scrub arguments structure and then use that progress in a call to resume scrub. So fix this by always copying the scrub arguments structure to user space, overwriting the value returned to user space with -EFAULT only if copying the structure failed to let user space know that either that copying did not happen, and therefore the structure is stale, or it happened partially and the structure is probably not valid and corrupt due to the partial copy. Reported-by: Graham Cobb <g.btrfs@cobb.uk.net> Link: https://lore.kernel.org/linux-btrfs/d0a97688-78be-08de-ca7d-bcb4c7fb397e@cobb.uk.net/ Fixes: 06fe39ab15a6a4 ("Btrfs: do not overwrite scrub error with fault error in scrub ioctl") CC: stable@vger.kernel.org # 5.1+ Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Qu Wenruo <wqu@suse.com> Tested-by: Graham Cobb <g.btrfs@cobb.uk.net> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * | | btrfs: relocation: fix reloc_root lifespan and accessQu Wenruo2020-01-131-5/+46
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [BUG] There are several different KASAN reports for balance + snapshot workloads. Involved call paths include: should_ignore_root+0x54/0xb0 [btrfs] build_backref_tree+0x11af/0x2280 [btrfs] relocate_tree_blocks+0x391/0xb80 [btrfs] relocate_block_group+0x3e5/0xa00 [btrfs] btrfs_relocate_block_group+0x240/0x4d0 [btrfs] btrfs_relocate_chunk+0x53/0xf0 [btrfs] btrfs_balance+0xc91/0x1840 [btrfs] btrfs_ioctl_balance+0x416/0x4e0 [btrfs] btrfs_ioctl+0x8af/0x3e60 [btrfs] do_vfs_ioctl+0x831/0xb10 create_reloc_root+0x9f/0x460 [btrfs] btrfs_reloc_post_snapshot+0xff/0x6c0 [btrfs] create_pending_snapshot+0xa9b/0x15f0 [btrfs] create_pending_snapshots+0x111/0x140 [btrfs] btrfs_commit_transaction+0x7a6/0x1360 [btrfs] btrfs_mksubvol+0x915/0x960 [btrfs] btrfs_ioctl_snap_create_transid+0x1d5/0x1e0 [btrfs] btrfs_ioctl_snap_create_v2+0x1d3/0x270 [btrfs] btrfs_ioctl+0x241b/0x3e60 [btrfs] do_vfs_ioctl+0x831/0xb10 btrfs_reloc_pre_snapshot+0x85/0xc0 [btrfs] create_pending_snapshot+0x209/0x15f0 [btrfs] create_pending_snapshots+0x111/0x140 [btrfs] btrfs_commit_transaction+0x7a6/0x1360 [btrfs] btrfs_mksubvol+0x915/0x960 [btrfs] btrfs_ioctl_snap_create_transid+0x1d5/0x1e0 [btrfs] btrfs_ioctl_snap_create_v2+0x1d3/0x270 [btrfs] btrfs_ioctl+0x241b/0x3e60 [btrfs] do_vfs_ioctl+0x831/0xb10 [CAUSE] All these call sites are only relying on root->reloc_root, which can undergo btrfs_drop_snapshot(), and since we don't have real refcount based protection to reloc roots, we can reach already dropped reloc root, triggering KASAN. [FIX] To avoid such access to unstable root->reloc_root, we should check BTRFS_ROOT_DEAD_RELOC_TREE bit first. This patch introduces wrappers that provide the correct way to check the bit with memory barriers protection. Most callers don't distinguish merged reloc tree and no reloc tree. The only exception is should_ignore_root(), as merged reloc tree can be ignored, while no reloc tree shouldn't. [CRITICAL SECTION ANALYSIS] Although test_bit()/set_bit()/clear_bit() doesn't imply a barrier, the DEAD_RELOC_TREE bit has extra help from transaction as a higher level barrier, the lifespan of root::reloc_root and DEAD_RELOC_TREE bit are: NULL: reloc_root is NULL PTR: reloc_root is not NULL 0: DEAD_RELOC_ROOT bit not set DEAD: DEAD_RELOC_ROOT bit set (NULL, 0) Initial state __ | /\ Section A btrfs_init_reloc_root() \/ | __ (PTR, 0) reloc_root initialized /\ | | btrfs_update_reloc_root() | Section B | | (PTR, DEAD) reloc_root has been merged \/ | __ === btrfs_commit_transaction() ==================== | /\ clean_dirty_subvols() | | | Section C (NULL, DEAD) reloc_root cleanup starts \/ | __ btrfs_drop_snapshot() /\ | | Section D (NULL, 0) Back to initial state \/ Every have_reloc_root() or test_bit(DEAD_RELOC_ROOT) caller holds transaction handle, so none of such caller can cross transaction boundary. In Section A, every caller just found no DEAD bit, and grab reloc_root. In the cross section A-B, caller may get no DEAD bit, but since reloc_root is still completely valid thus accessing reloc_root is completely safe. No test_bit() caller can cross the boundary of Section B and Section C. In Section C, every caller found the DEAD bit, so no one will access reloc_root. In the cross section C-D, either caller gets the DEAD bit set, avoiding access reloc_root no matter if it's safe or not. Or caller get the DEAD bit cleared, then access reloc_root, which is already NULL, nothing will be wrong. The memory write barriers are between the reloc_root updates and bit set/clear, the pairing read side is before test_bit. Reported-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org> Fixes: d2311e698578 ("btrfs: relocation: Delay reloc tree deletion after merge_reloc_roots") CC: stable@vger.kernel.org # 5.4+ Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> [ barriers ] Signed-off-by: David Sterba <dsterba@suse.com>
| * | | btrfs: fix memory leak in qgroup accountingJohannes Thumshirn2020-01-081-1/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When running xfstests on the current btrfs I get the following splat from kmemleak: unreferenced object 0xffff88821b2404e0 (size 32): comm "kworker/u4:7", pid 26663, jiffies 4295283698 (age 8.776s) hex dump (first 32 bytes): 01 00 00 00 00 00 00 00 10 ff fd 26 82 88 ff ff ...........&.... 10 ff fd 26 82 88 ff ff 20 ff fd 26 82 88 ff ff ...&.... ..&.... backtrace: [<00000000f94fd43f>] ulist_alloc+0x25/0x60 [btrfs] [<00000000fd023d99>] btrfs_find_all_roots_safe+0x41/0x100 [btrfs] [<000000008f17bd32>] btrfs_find_all_roots+0x52/0x70 [btrfs] [<00000000b7660afb>] btrfs_qgroup_rescan_worker+0x343/0x680 [btrfs] [<0000000058e66778>] btrfs_work_helper+0xac/0x1e0 [btrfs] [<00000000f0188930>] process_one_work+0x1cf/0x350 [<00000000af5f2f8e>] worker_thread+0x28/0x3c0 [<00000000b55a1add>] kthread+0x109/0x120 [<00000000f88cbd17>] ret_from_fork+0x35/0x40 This corresponds to: (gdb) l *(btrfs_find_all_roots_safe+0x41) 0x8d7e1 is in btrfs_find_all_roots_safe (fs/btrfs/backref.c:1413). 1408 1409 tmp = ulist_alloc(GFP_NOFS); 1410 if (!tmp) 1411 return -ENOMEM; 1412 *roots = ulist_alloc(GFP_NOFS); 1413 if (!*roots) { 1414 ulist_free(tmp); 1415 return -ENOMEM; 1416 } 1417 Following the lifetime of the allocated 'roots' ulist, it gets freed again in btrfs_qgroup_account_extent(). But this does not happen if the function is called with the 'BTRFS_FS_QUOTA_ENABLED' flag cleared, then btrfs_qgroup_account_extent() does a short leave and directly returns. Instead of directly returning we should jump to the 'out_free' in order to free all resources as expected. CC: stable@vger.kernel.org # 4.14+ Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> [ add comment ] Signed-off-by: David Sterba <dsterba@suse.com>
| * | | btrfs: do not delete mismatched root refsJosef Bacik2020-01-081-4/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | btrfs_del_root_ref() will simply WARN_ON() if the ref doesn't match in any way, and then continue to delete the reference. This shouldn't happen, we have these values because there's more to the reference than the original root and the sub root. If any of these checks fail, return -ENOENT. CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * | | btrfs: fix invalid removal of root refJosef Bacik2020-01-081-8/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If we have the following sequence of events btrfs sub create A btrfs sub create A/B btrfs sub snap A C mkdir C/foo mv A/B C/foo rm -rf * We will end up with a transaction abort. The reason for this is because we create a root ref for B pointing to A. When we create a snapshot of C we still have B in our tree, but because the root ref points to A and not C we will make it appear to be empty. The problem happens when we move B into C. This removes the root ref for B pointing to A and adds a ref of B pointing to C. When we rmdir C we'll see that we have a ref to our root and remove the root ref, despite not actually matching our reference name. Now btrfs_del_root_ref() allowing this to work is a bug as well, however we know that this inode does not actually point to a root ref in the first place, so we shouldn't be calling btrfs_del_root_ref() in the first place and instead simply look up our dir index for this item and do the rest of the removal. CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * | | btrfs: rework arguments of btrfs_unlink_subvolJosef Bacik2020-01-081-26/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | btrfs_unlink_subvol takes the name of the dentry and the root objectid based on what kind of inode this is, either a real subvolume link or a empty one that we inherited as a snapshot. We need to fix how we unlink in the case for BTRFS_EMPTY_SUBVOL_DIR_OBJECTID in the future, so rework btrfs_unlink_subvol to just take the dentry and handle getting the right objectid given the type of inode this is. There is no functional change here, simply pushing the work into btrfs_unlink_subvol() proper. Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* | | | Merge tag 'fuse-fixes-5.5-rc7' of ↵Linus Torvalds2020-01-171-1/+3
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse Pull fuse fix from Miklos Szeredi: "Fix a regression in the last release affecting the ftp module of the gvfs filesystem" * tag 'fuse-fixes-5.5-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse: fuse: fix fuse_send_readpages() in the syncronous read case
| * | | | fuse: fix fuse_send_readpages() in the syncronous read caseMiklos Szeredi2020-01-161-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Buffered read in fuse normally goes via: -> generic_file_buffered_read() -> fuse_readpages() -> fuse_send_readpages() ->fuse_simple_request() [called since v5.4] In the case of a read request, fuse_simple_request() will return a non-negative bytecount on success or a negative error value. A positive bytecount was taken to be an error and the PG_error flag set on the page. This resulted in generic_file_buffered_read() falling back to ->readpage(), which would repeat the read request and succeed. Because of the repeated read succeeding the bug was not detected with regression tests or other use cases. The FTP module in GVFS however fails the second read due to the non-seekable nature of FTP downloads. Fix by checking and ignoring positive return value from fuse_simple_request(). Reported-by: Ondrej Holy <oholy@redhat.com> Link: https://gitlab.gnome.org/GNOME/gvfs/issues/441 Fixes: 134831e36bbd ("fuse: convert readpages to simple api") Cc: <stable@vger.kernel.org> # v5.4 Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* | | | | Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfsLinus Torvalds2020-01-152-79/+13
|\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull vfs fixes from Al Viro: "Fixes for mountpoint_last() bugs (by converting to use of lookup_last()) and an autofs regression fix from this cycle (caused by follow_managed() breakage introduced in barrier fixes series)" * 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: fix autofs regression caused by follow_managed() changes reimplement path_mountpoint() with less magic
| * | | | | fix autofs regression caused by follow_managed() changesAl Viro2020-01-151-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | we need to reload ->d_flags after the call of ->d_manage() - the thing might've been called with dentry still negative and have the damn thing turned positive while we'd waited. Fixes: d41efb522e90 "fs/namei.c: pull positivity check into follow_managed()" Reported-by: Ian Kent <raven@themaw.net> Tested-by: Ian Kent <raven@themaw.net> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| * | | | | reimplement path_mountpoint() with less magicAl Viro2020-01-152-79/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ... and get rid of a bunch of bugs in it. Background: the reason for path_mountpoint() is that umount() really doesn't want attempts to revalidate the root of what it's trying to umount. The thing we want to avoid actually happen from complete_walk(); solution was to do something parallel to normal path_lookupat() and it both went overboard and got the boilerplate subtly (and not so subtly) wrong. A better solution is to do pretty much what the normal path_lookupat() does, but instead of complete_walk() do unlazy_walk(). All it takes to avoid that ->d_weak_revalidate() call... mountpoint_last() goes away, along with everything it got wrong, and so does the magic around LOOKUP_NO_REVAL. Another source of bugs is that when we traverse mounts at the final location (and we need to do that - umount . expects to get whatever's overmounting ., if any, out of the lookup) we really ought to take care of ->d_manage() - as it is, manual umount of autofs automount in progress can lead to unpleasant surprises for the daemon. Easily solved by using handle_lookup_down() instead of follow_mount(). Tested-by: Ian Kent <raven@themaw.net> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | | | | | Merge branch 'dhowells' (patches from DavidH)Linus Torvalds2020-01-141-10/+8
|\ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Merge misc fixes from David Howells. Two afs fixes and a key refcounting fix. * dhowells: afs: Fix afs_lookup() to not clobber the version on a new dentry afs: Fix use-after-loss-of-ref keys: Fix request_key() cache
| * | | | | | afs: Fix afs_lookup() to not clobber the version on a new dentryDavid Howells2020-01-141-5/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix afs_lookup() to not clobber the version set on a new dentry by afs_do_lookup() - especially as it's using the wrong version of the version (we need to use the one given to us by whatever op the dir contents correspond to rather than what's in the afs_vnode). Fixes: 9dd0b82ef530 ("afs: Fix missing dentry data version updating") Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | | | | afs: Fix use-after-loss-of-refDavid Howells2020-01-141-5/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | afs_lookup() has a tracepoint to indicate the outcome of d_splice_alias(), passing it the inode to retrieve the fid from. However, the function gave up its ref on that inode when it called d_splice_alias(), which may have failed and dropped the inode. Fix this by caching the fid. Fixes: 80548b03991f ("afs: Add more tracepoints") Reported-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | | | | | Merge tag 'char-misc-5.5-rc6' of ↵Linus Torvalds2020-01-101-1/+1
|\ \ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc Pull char/misc fix from Greg KH: "Here is a single fix, for the chrdev core, for 5.5-rc6 There's been a long-standing race condition triggered by syzbot, and occasionally real people, in the chrdev open() path. Will finally took the time to track it down and fix it for real before the holidays. Here's that one patch, it's been in linux-next for a while with no reported issues and it does fix the reported problem" * tag 'char-misc-5.5-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: chardev: Avoid potential use-after-free in 'chrdev_open()'
| * | | | | | | chardev: Avoid potential use-after-free in 'chrdev_open()'Will Deacon2020-01-061-1/+1
| | |_|_|_|_|/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 'chrdev_open()' calls 'cdev_get()' to obtain a reference to the 'struct cdev *' stashed in the 'i_cdev' field of the target inode structure. If the pointer is NULL, then it is initialised lazily by looking up the kobject in the 'cdev_map' and so the whole procedure is protected by the 'cdev_lock' spinlock to serialise initialisation of the shared pointer. Unfortunately, it is possible for the initialising thread to fail *after* installing the new pointer, for example if the subsequent '->open()' call on the file fails. In this case, 'cdev_put()' is called, the reference count on the kobject is dropped and, if nobody else has taken a reference, the release function is called which finally clears 'inode->i_cdev' from 'cdev_purge()' before potentially freeing the object. The problem here is that a racing thread can happily take the 'cdev_lock' and see the non-NULL pointer in the inode, which can result in a refcount increment from zero and a warning: | ------------[ cut here ]------------ | refcount_t: addition on 0; use-after-free. | WARNING: CPU: 2 PID: 6385 at lib/refcount.c:25 refcount_warn_saturate+0x6d/0xf0 | Modules linked in: | CPU: 2 PID: 6385 Comm: repro Not tainted 5.5.0-rc2+ #22 | Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 | RIP: 0010:refcount_warn_saturate+0x6d/0xf0 | Code: 05 55 9a 15 01 01 e8 9d aa c8 ff 0f 0b c3 80 3d 45 9a 15 01 00 75 ce 48 c7 c7 00 9c 62 b3 c6 08 | RSP: 0018:ffffb524c1b9bc70 EFLAGS: 00010282 | RAX: 0000000000000000 RBX: ffff9e9da1f71390 RCX: 0000000000000000 | RDX: ffff9e9dbbd27618 RSI: ffff9e9dbbd18798 RDI: ffff9e9dbbd18798 | RBP: 0000000000000000 R08: 000000000000095f R09: 0000000000000039 | R10: 0000000000000000 R11: ffffb524c1b9bb20 R12: ffff9e9da1e8c700 | R13: ffffffffb25ee8b0 R14: 0000000000000000 R15: ffff9e9da1e8c700 | FS: 00007f3b87d26700(0000) GS:ffff9e9dbbd00000(0000) knlGS:0000000000000000 | CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 | CR2: 00007fc16909c000 CR3: 000000012df9c000 CR4: 00000000000006e0 | DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 | DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 | Call Trace: | kobject_get+0x5c/0x60 | cdev_get+0x2b/0x60 | chrdev_open+0x55/0x220 | ? cdev_put.part.3+0x20/0x20 | do_dentry_open+0x13a/0x390 | path_openat+0x2c8/0x1470 | do_filp_open+0x93/0x100 | ? selinux_file_ioctl+0x17f/0x220 | do_sys_open+0x186/0x220 | do_syscall_64+0x48/0x150 | entry_SYSCALL_64_after_hwframe+0x44/0xa9 | RIP: 0033:0x7f3b87efcd0e | Code: 89 54 24 08 e8 a3 f4 ff ff 8b 74 24 0c 48 8b 3c 24 41 89 c0 44 8b 54 24 08 b8 01 01 00 00 89 f4 | RSP: 002b:00007f3b87d259f0 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 | RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f3b87efcd0e | RDX: 0000000000000000 RSI: 00007f3b87d25a80 RDI: 00000000ffffff9c | RBP: 00007f3b87d25e90 R08: 0000000000000000 R09: 0000000000000000 | R10: 0000000000000000 R11: 0000000000000293 R12: 00007ffe188f504e | R13: 00007ffe188f504f R14: 00007f3b87d26700 R15: 0000000000000000 | ---[ end trace 24f53ca58db8180a ]--- Since 'cdev_get()' can already fail to obtain a reference, simply move it over to use 'kobject_get_unless_zero()' instead of 'kobject_get()', which will cause the racing thread to return -ENXIO if the initialising thread fails unexpectedly. Cc: Hillf Danton <hdanton@sina.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Reported-by: syzbot+82defefbbd8527e1c2cb@syzkaller.appspotmail.com Signed-off-by: Will Deacon <will@kernel.org> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20191219120203.32691-1-will@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | | | | | | Merge tag 'block-5.5-2020-01-10' of git://git.kernel.dk/linux-blockLinus Torvalds2020-01-103-6/+6
|\ \ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull block fixes from Jens Axboe: "A few fixes that should go into this round. This pull request contains two NVMe fixes via Keith, removal of a dead function, and a fix for the bio op for read truncates (Ming)" * tag 'block-5.5-2020-01-10' of git://git.kernel.dk/linux-block: nvmet: fix per feat data len for get_feature nvme: Translate more status codes to blk_status_t fs: move guard_bio_eod() after bio_set_op_attrs block: remove unused mp_bvec_last_segment
| * | | | | | | fs: move guard_bio_eod() after bio_set_op_attrsMing Lei2020-01-093-6/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 85a8ce62c2ea ("block: add bio_truncate to fix guard_bio_eod") adds bio_truncate() for handling bio EOD. However, bio_truncate() doesn't use the passed 'op' parameter from guard_bio_eod's callers. So bio_trunacate() may retrieve wrong 'op', and zering pages may not be done for READ bio. Fixes this issue by moving guard_bio_eod() after bio_set_op_attrs() in submit_bh_wbc() so that bio_truncate() can always retrieve correct op info. Meantime remove the 'op' parameter from guard_bio_eod() because it isn't used any more. Cc: Carlos Maiolino <cmaiolino@redhat.com> Cc: linux-fsdevel@vger.kernel.org Fixes: 85a8ce62c2ea ("block: add bio_truncate to fix guard_bio_eod") Signed-off-by: Ming Lei <ming.lei@redhat.com> Fold in kerneldoc and bio_op() change. Signed-off-by: Jens Axboe <axboe@kernel.dk>
* | | | | | | | Merge tag 'io_uring-5.5-2020-01-10' of git://git.kernel.dk/linux-blockLinus Torvalds2020-01-101-12/+0
|\ \ \ \ \ \ \ \ | | |_|_|_|_|_|/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull io_uring fix from Jens Axboe: "Single fix for this series, fixing a regression with the short read handling. This just removes it, as it cannot safely be done for all cases" * tag 'io_uring-5.5-2020-01-10' of git://git.kernel.dk/linux-block: io_uring: remove punt of short reads to async context
| * | | | | | | io_uring: remove punt of short reads to async contextJens Axboe2020-01-071-12/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We currently punt any short read on a regular file to async context, but this fails if the short read is due to running into EOF. This is especially problematic since we only do the single prep for commands now, as we don't reset kiocb->ki_pos. This can result in a 4k read on a 1k file returning zero, as we detect the short read and then retry from async context. At the time of retry, the position is now 1k, and we end up reading nothing, and hence return 0. Instead of trying to patch around the fact that short reads can be legitimate and won't succeed in case of retry, remove the logic to punt a short read to async context. Simply return it. Signed-off-by: Jens Axboe <axboe@kernel.dk>
* | | | | | | | Merge tag 'pstore-v5.5-rc6' of ↵Linus Torvalds2020-01-102-3/+3
|\ \ \ \ \ \ \ \ | |_|_|/ / / / / |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull pstore fix from Kees Cook: "Cengiz Can forwarded a Coverity report about more problems with a rare pstore initialization error path, so the allocation lifetime was rearranged to avoid needing to share the kfree() responsibilities between caller and callee" * tag 'pstore-v5.5-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: pstore/ram: Regularize prz label allocation lifetime
| * | | | | | | pstore/ram: Regularize prz label allocation lifetimeKees Cook2020-01-092-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In my attempt to fix a memory leak, I introduced a double-free in the pstore error path. Instead of trying to manage the allocation lifetime between persistent_ram_new() and its callers, adjust the logic so persistent_ram_new() always takes a kstrdup() copy, and leaves the caller's allocation lifetime up to the caller. Therefore callers are _always_ responsible for freeing their label. Before, it only needed freeing when the prz itself failed to allocate, and not in any of the other prz failure cases, which callers would have no visibility into, which is the root design problem that lead to both the leak and now double-free bugs. Reported-by: Cengiz Can <cengiz@kernel.wtf> Link: https://lore.kernel.org/lkml/d4ec59002ede4aaf9928c7f7526da87c@kernel.wtf Fixes: 8df955a32a73 ("pstore/ram: Fix error-path memory leak in persistent_ram_new() callers") Cc: stable@vger.kernel.org Signed-off-by: Kees Cook <keescook@chromium.org>
* | | | | | | | ocfs2: fix the crash due to call ocfs2_get_dlm_debug once lessGang He2020-01-041-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Because ocfs2_get_dlm_debug() function is called once less here, ocfs2 file system will trigger the system crash, usually after ocfs2 file system is unmounted. This system crash is caused by a generic memory corruption, these crash backtraces are not always the same, for exapmle, ocfs2: Unmounting device (253,16) on (node 172167785) general protection fault: 0000 [#1] SMP PTI CPU: 3 PID: 14107 Comm: fence_legacy Kdump: Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) RIP: 0010:__kmalloc+0xa5/0x2a0 Code: 00 00 4d 8b 07 65 4d 8b RSP: 0018:ffffaa1fc094bbe8 EFLAGS: 00010286 RAX: 0000000000000000 RBX: d310a8800d7a3faf RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000dc0 RDI: ffff96e68fc036c0 RBP: d310a8800d7a3faf R08: ffff96e6ffdb10a0 R09: 00000000752e7079 R10: 000000000001c513 R11: 0000000004091041 R12: 0000000000000dc0 R13: 0000000000000039 R14: ffff96e68fc036c0 R15: ffff96e68fc036c0 FS: 00007f699dfba540(0000) GS:ffff96e6ffd80000(0000) knlGS:00000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055f3a9d9b768 CR3: 000000002cd1c000 CR4: 00000000000006e0 Call Trace: ext4_htree_store_dirent+0x35/0x100 [ext4] htree_dirblock_to_tree+0xea/0x290 [ext4] ext4_htree_fill_tree+0x1c1/0x2d0 [ext4] ext4_readdir+0x67c/0x9d0 [ext4] iterate_dir+0x8d/0x1a0 __x64_sys_getdents+0xab/0x130 do_syscall_64+0x60/0x1f0 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f699d33a9fb This regression problem was introduced by commit e581595ea29c ("ocfs: no need to check return value of debugfs_create functions"). Link: http://lkml.kernel.org/r/20191225061501.13587-1-ghe@suse.com Fixes: e581595ea29c ("ocfs: no need to check return value of debugfs_create functions") Signed-off-by: Gang He <ghe@suse.com> Acked-by: Joseph Qi <joseph.qi@linux.alibaba.com> Cc: Mark Fasheh <mark@fasheh.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Changwei Ge <gechangwei@live.cn> Cc: Gang He <ghe@suse.com> Cc: Jun Piao <piaojun@huawei.com> Cc: <stable@vger.kernel.org> [5.3+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | | | | | | ocfs2: call journal flush to mark journal as empty after journal recovery ↵Kai Li2020-01-041-0/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | when mount If journal is dirty when mount, it will be replayed but jbd2 sb log tail cannot be updated to mark a new start because journal->j_flag has already been set with JBD2_ABORT first in journal_init_common. When a new transaction is committed, it will be recored in block 1 first(journal->j_tail is set to 1 in journal_reset). If emergency restart happens again before journal super block is updated unfortunately, the new recorded trans will not be replayed in the next mount. The following steps describe this procedure in detail. 1. mount and touch some files 2. these transactions are committed to journal area but not checkpointed 3. emergency restart 4. mount again and its journals are replayed 5. journal super block's first s_start is 1, but its s_seq is not updated 6. touch a new file and its trans is committed but not checkpointed 7. emergency restart again 8. mount and journal is dirty, but trans committed in 6 will not be replayed. This exception happens easily when this lun is used by only one node. If it is used by multi-nodes, other node will replay its journal and its journal super block will be updated after recovery like what this patch does. ocfs2_recover_node->ocfs2_replay_journal. The following jbd2 journal can be generated by touching a new file after journal is replayed, and seq 15 is the first valid commit, but first seq is 13 in journal super block. logdump: Block 0: Journal Superblock Seq: 0 Type: 4 (JBD2_SUPERBLOCK_V2) Blocksize: 4096 Total Blocks: 32768 First Block: 1 First Commit ID: 13 Start Log Blknum: 1 Error: 0 Feature Compat: 0 Feature Incompat: 2 block64 Feature RO compat: 0 Journal UUID: 4ED3822C54294467A4F8E87D2BA4BC36 FS Share Cnt: 1 Dynamic Superblk Blknum: 0 Per Txn Block Limit Journal: 0 Data: 0 Block 1: Journal Commit Block Seq: 14 Type: 2 (JBD2_COMMIT_BLOCK) Block 2: Journal Descriptor Seq: 15 Type: 1 (JBD2_DESCRIPTOR_BLOCK) No. Blocknum Flags 0. 587 none UUID: 00000000000000000000000000000000 1. 8257792 JBD2_FLAG_SAME_UUID 2. 619 JBD2_FLAG_SAME_UUID 3. 24772864 JBD2_FLAG_SAME_UUID 4. 8257802 JBD2_FLAG_SAME_UUID 5. 513 JBD2_FLAG_SAME_UUID JBD2_FLAG_LAST_TAG ... Block 7: Inode Inode: 8257802 Mode: 0640 Generation: 57157641 (0x3682809) FS Generation: 2839773110 (0xa9437fb6) CRC32: 00000000 ECC: 0000 Type: Regular Attr: 0x0 Flags: Valid Dynamic Features: (0x1) InlineData User: 0 (root) Group: 0 (root) Size: 7 Links: 1 Clusters: 0 ctime: 0x5de5d870 0x11104c61 -- Tue Dec 3 11:37:20.286280801 2019 atime: 0x5de5d870 0x113181a1 -- Tue Dec 3 11:37:20.288457121 2019 mtime: 0x5de5d870 0x11104c61 -- Tue Dec 3 11:37:20.286280801 2019 dtime: 0x0 -- Thu Jan 1 08:00:00 1970 ... Block 9: Journal Commit Block Seq: 15 Type: 2 (JBD2_COMMIT_BLOCK) The following is journal recovery log when recovering the upper jbd2 journal when mount again. syslog: ocfs2: File system on device (252,1) was not unmounted cleanly, recovering it. fs/jbd2/recovery.c:(do_one_pass, 449): Starting recovery pass 0 fs/jbd2/recovery.c:(do_one_pass, 449): Starting recovery pass 1 fs/jbd2/recovery.c:(do_one_pass, 449): Starting recovery pass 2 fs/jbd2/recovery.c:(jbd2_journal_recover, 278): JBD2: recovery, exit status 0, recovered transactions 13 to 13 Due to first commit seq 13 recorded in journal super is not consistent with the value recorded in block 1(seq is 14), journal recovery will be terminated before seq 15 even though it is an unbroken commit, inode 8257802 is a new file and it will be lost. Link: http://lkml.kernel.org/r/20191217020140.2197-1-li.kai4@h3c.com Signed-off-by: Kai Li <li.kai4@h3c.com> Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com> Reviewed-by: Changwei Ge <gechangwei@live.cn> Cc: Mark Fasheh <mark@fasheh.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Gang He <ghe@suse.com> Cc: Jun Piao <piaojun@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | | | | | | fs/posix_acl.c: fix kernel-doc warningsRandy Dunlap2020-01-041-2/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix kernel-doc warnings in fs/posix_acl.c. Also fix one typo (setgit -> setgid). fs/posix_acl.c:647: warning: Function parameter or member 'inode' not described in 'posix_acl_update_mode' fs/posix_acl.c:647: warning: Function parameter or member 'mode_p' not described in 'posix_acl_update_mode' fs/posix_acl.c:647: warning: Function parameter or member 'acl' not described in 'posix_acl_update_mode' Link: http://lkml.kernel.org/r/29b0dc46-1f28-a4e5-b1d0-ba2b65629779@infradead.org Fixes: 073931017b49d ("posix_acl: Clear SGID bit when setting file permissions") Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Acked-by: Andreas Gruenbacher <agruenba@redhat.com> Reviewed-by: Jan Kara <jack@suse.cz> Cc: Jan Kara <jack@suse.cz> Cc: Andreas Gruenbacher <agruenba@redhat.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | | | | | | fs/namespace.c: make to_mnt_ns() staticEric Biggers2020-01-041-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make to_mnt_ns() static to address the following 'sparse' warning: fs/namespace.c:1731:22: warning: symbol 'to_mnt_ns' was not declared. Should it be static? Link: http://lkml.kernel.org/r/20191209234830.156260-1-ebiggers@kernel.org Signed-off-by: Eric Biggers <ebiggers@google.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | | | | | | fs/nsfs.c: include headers for missing declarationsEric Biggers2020-01-041-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Include linux/proc_fs.h and fs/internal.h to address the following 'sparse' warnings: fs/nsfs.c:41:32: warning: symbol 'ns_dentry_operations' was not declared. Should it be static? fs/nsfs.c:145:5: warning: symbol 'open_related_ns' was not declared. Should it be static? Link: http://lkml.kernel.org/r/20191209234822.156179-1-ebiggers@kernel.org Signed-off-by: Eric Biggers <ebiggers@google.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | | | | | | fs/direct-io.c: include fs/internal.h for missing prototypeEric Biggers2020-01-041-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Include fs/internal.h to address the following 'sparse' warning: fs/direct-io.c:591:5: warning: symbol 'sb_init_dio_done_wq' was not declared. Should it be static? Link: http://lkml.kernel.org/r/20191209234544.128302-1-ebiggers@kernel.org Signed-off-by: Eric Biggers <ebiggers@google.com> Reviewed-by: Jan Kara <jack@suse.cz> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | | | | | | Merge tag 'for-5.5-rc4-tag' of ↵Linus Torvalds2020-01-032-4/+9
|\ \ \ \ \ \ \ \ | | |_|_|_|_|_|/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs fixes from David Sterba: "A few fixes for btrfs: - blkcg accounting problem with compression that could stall writes - setting up blkcg bio for compression crashes due to NULL bdev pointer - fix possible infinite loop in writeback for nocow files (here possible means almost impossible, 13 things that need to happen to trigger it)" * tag 'for-5.5-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: Btrfs: fix infinite loop during nocow writeback due to race btrfs: fix compressed write bio blkcg attribution btrfs: punt all bios created in btrfs_submit_compressed_write()
| * | | | | | | Btrfs: fix infinite loop during nocow writeback due to raceFilipe Manana2019-12-301-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When starting writeback for a range that covers part of a preallocated extent, due to a race with writeback for another range that also covers another part of the same preallocated extent, we can end up in an infinite loop. Consider the following example where for inode 280 we have two dirty ranges: range A, from 294912 to 303103, 8192 bytes range B, from 348160 to 438271, 90112 bytes and we have the following file extent item layout for our inode: leaf 38895616 gen 24544 total ptrs 29 free space 13820 owner 5 (...) item 27 key (280 108 200704) itemoff 14598 itemsize 53 extent data disk bytenr 0 nr 0 type 1 (regular) extent data offset 0 nr 94208 ram 94208 item 28 key (280 108 294912) itemoff 14545 itemsize 53 extent data disk bytenr 10433052672 nr 81920 type 2 (prealloc) extent data offset 0 nr 81920 ram 81920 Then the following happens: 1) Writeback starts for range B (from 348160 to 438271), execution of run_delalloc_nocow() starts; 2) The first iteration of run_delalloc_nocow()'s whil loop leaves us at the extent item at slot 28, pointing to the prealloc extent item covering the range from 294912 to 376831. This extent covers part of our range; 3) An ordered extent is created against that extent, covering the file range from 348160 to 376831 (28672 bytes); 4) We adjust 'cur_offset' to 376832 and move on to the next iteration of the while loop; 5) The call to btrfs_lookup_file_extent() leaves us at the same leaf, pointing to slot 29, 1 slot after the last item (the extent item we processed in the previous iteration); 6) Because we are a slot beyond the last item, we call btrfs_next_leaf(), which releases the search path before doing a another search for the last key of the leaf (280 108 294912); 7) Right after btrfs_next_leaf() released the path, and before it did another search for the last key of the leaf, writeback for the range A (from 294912 to 303103) completes (it was previously started at some point); 8) Upon completion of the ordered extent for range A, the prealloc extent we previously found got split into two extent items, one covering the range from 294912 to 303103 (8192 bytes), with a type of regular extent (and no longer prealloc) and another covering the range from 303104 to 376831 (73728 bytes), with a type of prealloc and an offset of 8192 bytes. So our leaf now has the following layout: leaf 38895616 gen 24544 total ptrs 31 free space 13664 owner 5 (...) item 27 key (280 108 200704) itemoff 14598 itemsize 53 extent data disk bytenr 0 nr 0 type 1 extent data offset 0 nr 8192 ram 94208 item 28 key (280 108 208896) itemoff 14545 itemsize 53 extent data disk bytenr 10433142784 nr 86016 type 1 extent data offset 0 nr 86016 ram 86016 item 29 key (280 108 294912) itemoff 14492 itemsize 53 extent data disk bytenr 10433052672 nr 81920 type 1 extent data offset 0 nr 8192 ram 81920 item 30 key (280 108 303104) itemoff 14439 itemsize 53 extent data disk bytenr 10433052672 nr 81920 type 2 extent data offset 8192 nr 73728 ram 81920 9) After btrfs_next_leaf() returns, we have our path pointing to that same leaf and at slot 30, since it has a key we didn't have before and it's the first key greater then the key that was previously the last key of the leaf (key (280 108 294912)); 10) The extent item at slot 30 covers the range from 303104 to 376831 which is in our target range, so we process it, despite having already created an ordered extent against this extent for the file range from 348160 to 376831. This is because we skip to the next extent item only if its end is less than or equals to the start of our delalloc range, and not less than or equals to the current offset ('cur_offset'); 11) As a result we compute 'num_bytes' as: num_bytes = min(end + 1, extent_end) - cur_offset; = min(438271 + 1, 376832) - 376832 = 0 12) We then call create_io_em() for a 0 bytes range starting at offset 376832; 13) Then create_io_em() enters an infinite loop because its calls to btrfs_drop_extent_cache() do nothing due to the 0 length range passed to it. So no existing extent maps that cover the offset 376832 get removed, and therefore calls to add_extent_mapping() return -EEXIST, resulting in an infinite loop. This loop from create_io_em() is the following: do { btrfs_drop_extent_cache(BTRFS_I(inode), em->start, em->start + em->len - 1, 0); write_lock(&em_tree->lock); ret = add_extent_mapping(em_tree, em, 1); write_unlock(&em_tree->lock); /* * The caller has taken lock_extent(), who could race with us * to add em? */ } while (ret == -EEXIST); Also, each call to btrfs_drop_extent_cache() triggers a warning because the start offset passed to it (376832) is smaller then the end offset (376832 - 1) passed to it by -1, due to the 0 length: [258532.052621] ------------[ cut here ]------------ [258532.052643] WARNING: CPU: 0 PID: 9987 at fs/btrfs/file.c:602 btrfs_drop_extent_cache+0x3f4/0x590 [btrfs] (...) [258532.052672] CPU: 0 PID: 9987 Comm: fsx Tainted: G W 5.4.0-rc7-btrfs-next-64 #1 [258532.052673] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-0-ga698c8995f-prebuilt.qemu.org 04/01/2014 [258532.052691] RIP: 0010:btrfs_drop_extent_cache+0x3f4/0x590 [btrfs] (...) [258532.052695] RSP: 0018:ffffb4be0153f860 EFLAGS: 00010287 [258532.052700] RAX: ffff975b445ee360 RBX: ffff975b44eb3e08 RCX: 0000000000000000 [258532.052700] RDX: 0000000000038fff RSI: 0000000000039000 RDI: ffff975b445ee308 [258532.052700] RBP: 0000000000038fff R08: 0000000000000000 R09: 0000000000000001 [258532.052701] R10: ffff975b513c5c10 R11: 00000000e3c0cfa9 R12: 0000000000039000 [258532.052703] R13: ffff975b445ee360 R14: 00000000ffffffef R15: ffff975b445ee308 [258532.052705] FS: 00007f86a821de80(0000) GS:ffff975b76a00000(0000) knlGS:0000000000000000 [258532.052707] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [258532.052708] CR2: 00007fdacf0f3ab4 CR3: 00000001f9d26002 CR4: 00000000003606f0 [258532.052712] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [258532.052717] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [258532.052717] Call Trace: [258532.052718] ? preempt_schedule_common+0x32/0x70 [258532.052722] ? ___preempt_schedule+0x16/0x20 [258532.052741] create_io_em+0xff/0x180 [btrfs] [258532.052767] run_delalloc_nocow+0x942/0xb10 [btrfs] [258532.052791] btrfs_run_delalloc_range+0x30b/0x520 [btrfs] [258532.052812] ? find_lock_delalloc_range+0x221/0x250 [btrfs] [258532.052834] writepage_delalloc+0xe4/0x140 [btrfs] [258532.052855] __extent_writepage+0x110/0x4e0 [btrfs] [258532.052876] extent_write_cache_pages+0x21c/0x480 [btrfs] [258532.052906] extent_writepages+0x52/0xb0 [btrfs] [258532.052911] do_writepages+0x23/0x80 [258532.052915] __filemap_fdatawrite_range+0xd2/0x110 [258532.052938] btrfs_fdatawrite_range+0x1b/0x50 [btrfs] [258532.052954] start_ordered_ops+0x57/0xa0 [btrfs] [258532.052973] ? btrfs_sync_file+0x225/0x490 [btrfs] [258532.052988] btrfs_sync_file+0x225/0x490 [btrfs] [258532.052997] __x64_sys_msync+0x199/0x200 [258532.053004] do_syscall_64+0x5c/0x250 [258532.053007] entry_SYSCALL_64_after_hwframe+0x49/0xbe [258532.053010] RIP: 0033:0x7f86a7dfd760 (...) [258532.053014] RSP: 002b:00007ffd99af0368 EFLAGS: 00000246 ORIG_RAX: 000000000000001a [258532.053016] RAX: ffffffffffffffda RBX: 0000000000000ec9 RCX: 00007f86a7dfd760 [258532.053017] RDX: 0000000000000004 RSI: 000000000000836c RDI: 00007f86a8221000 [258532.053019] RBP: 0000000000021ec9 R08: 0000000000000003 R09: 00007f86a812037c [258532.053020] R10: 0000000000000001 R11: 0000000000000246 R12: 00000000000074a3 [258532.053021] R13: 00007f86a8221000 R14: 000000000000836c R15: 0000000000000001 [258532.053032] irq event stamp: 1653450494 [258532.053035] hardirqs last enabled at (1653450493): [<ffffffff9dec69f9>] _raw_spin_unlock_irq+0x29/0x50 [258532.053037] hardirqs last disabled at (1653450494): [<ffffffff9d4048ea>] trace_hardirqs_off_thunk+0x1a/0x20 [258532.053039] softirqs last enabled at (1653449852): [<ffffffff9e200466>] __do_softirq+0x466/0x6bd [258532.053042] softirqs last disabled at (1653449845): [<ffffffff9d4c8a0c>] irq_exit+0xec/0x120 [258532.053043] ---[ end trace 8476fce13d9ce20a ]--- Which results in flooding dmesg/syslog since btrfs_drop_extent_cache() uses WARN_ON() and not WARN_ON_ONCE(). So fix this issue by changing run_delalloc_nocow()'s loop to move to the next extent item when the current extent item ends at at offset less than or equals to the current offset instead of the start offset. Fixes: 80ff385665b7fc ("Btrfs: update nodatacow code v2") CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>