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* kernel/resource: move and rename IORESOURCE_MEM_DRIVER_MANAGEDDavid Hildenbrand2020-10-161-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | IORESOURCE_MEM_DRIVER_MANAGED currently uses an unused PnP bit, which is always set to 0 by hardware. This is far from beautiful (and confusing), and the bit only applies to SYSRAM. So let's move it out of the bus-specific (PnP) defined bits. We'll add another SYSRAM specific bit soon. If we ever need more bits for other purposes, we can steal some from "desc", or reshuffle/regroup what we have. Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Kees Cook <keescook@chromium.org> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: Baoquan He <bhe@redhat.com> Cc: Wei Yang <richardw.yang@linux.intel.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Anton Blanchard <anton@ozlabs.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Julien Grall <julien@xen.org> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Len Brown <lenb@kernel.org> Cc: Leonardo Bras <leobras.c@gmail.com> Cc: Libor Pechacek <lpechacek@suse.cz> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Nathan Lynch <nathanl@linux.ibm.com> Cc: "Oliver O'Halloran" <oohall@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Pingfan Liu <kernelfans@gmail.com> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Roger Pau Monné <roger.pau@citrix.com> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: Stephen Hemminger <sthemmin@microsoft.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Wei Liu <wei.liu@kernel.org> Link: https://lkml.kernel.org/r/20200911103459.10306-3-david@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* fs/kernel_file_read: Add "offset" arg for partial readsKees Cook2020-10-051-2/+2
| | | | | | | | | | | | | | To perform partial reads, callers of kernel_read_file*() must have a non-NULL file_size argument and a preallocated buffer. The new "offset" argument can then be used to seek to specific locations in the file to fill the buffer to, at most, "buf_size" per call. Where possible, the LSM hooks can report whether a full file has been read or not so that the contents can be reasoned about. Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20201002173828.2099543-14-keescook@chromium.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* fs/kernel_read_file: Add file_size output argumentKees Cook2020-10-051-2/+2
| | | | | | | | | | | | | | In preparation for adding partial read support, add an optional output argument to kernel_read_file*() that reports the file size so callers can reason more easily about their reading progress. Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com> Reviewed-by: Luis Chamberlain <mcgrof@kernel.org> Reviewed-by: James Morris <jamorris@linux.microsoft.com> Acked-by: Scott Branden <scott.branden@broadcom.com> Link: https://lore.kernel.org/r/20201002173828.2099543-8-keescook@chromium.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* fs/kernel_read_file: Remove redundant size argumentKees Cook2020-10-051-7/+7
| | | | | | | | | | | | | | | In preparation for refactoring kernel_read_file*(), remove the redundant "size" argument which is not needed: it can be included in the return code, with callers adjusted. (VFS reads already cannot be larger than INT_MAX.) Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com> Reviewed-by: Luis Chamberlain <mcgrof@kernel.org> Reviewed-by: James Morris <jamorris@linux.microsoft.com> Acked-by: Scott Branden <scott.branden@broadcom.com> Link: https://lore.kernel.org/r/20201002173828.2099543-6-keescook@chromium.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* fs/kernel_read_file: Split into separate include fileScott Branden2020-10-051-0/+1
| | | | | | | | | | | | | | | | | | Move kernel_read_file* out of linux/fs.h to its own linux/kernel_read_file.h include file. That header gets pulled in just about everywhere and doesn't really need functions not related to the general fs interface. Suggested-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Scott Branden <scott.branden@broadcom.com> Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com> Reviewed-by: Luis Chamberlain <mcgrof@kernel.org> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: James Morris <jamorris@linux.microsoft.com> Link: https://lore.kernel.org/r/20200706232309.12010-2-scott.branden@broadcom.com Link: https://lore.kernel.org/r/20201002173828.2099543-4-keescook@chromium.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Merge tag 'x86-urgent-2020-08-15' of ↵Linus Torvalds2020-08-151-15/+26
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Ingo Molnar: "Misc fixes and small updates all around the place: - Fix mitigation state sysfs output - Fix an FPU xstate/sxave code assumption bug triggered by Architectural LBR support - Fix Lightning Mountain SoC TSC frequency enumeration bug - Fix kexec debug output - Fix kexec memory range assumption bug - Fix a boundary condition in the crash kernel code - Optimize porgatory.ro generation a bit - Enable ACRN guests to use X2APIC mode - Reduce a __text_poke() IRQs-off critical section for the benefit of PREEMPT_RT" * tag 'x86-urgent-2020-08-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/alternatives: Acquire pte lock with interrupts enabled x86/bugs/multihit: Fix mitigation reporting when VMX is not in use x86/fpu/xstate: Fix an xstate size check warning with architectural LBRs x86/purgatory: Don't generate debug info for purgatory.ro x86/tsr: Fix tsc frequency enumeration bug on Lightning Mountain SoC kexec_file: Correctly output debugging information for the PT_LOAD ELF header kexec: Improve & fix crash_exclude_mem_range() to handle overlapping ranges x86/crash: Correct the address boundary of function parameters x86/acrn: Remove redundant chars from ACRN signature x86/acrn: Allow ACRN guest to use X2APIC mode
| * kexec_file: Correctly output debugging information for the PT_LOAD ELF headerLianbo Jiang2020-08-071-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, when we enable the debugging switch to debug kexec_file, we always get the following incorrect results: kexec_file: Crash PT_LOAD elf header. phdr=00000000c988639b vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=51 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=000000003cca69a0 vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=52 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000c584cb9f vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=53 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000cf85d57f vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=54 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000a4a8f847 vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=55 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000272ec49f vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=56 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000ea0b65de vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=57 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=000000001f5e490c vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=58 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000dfe4109e vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=59 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000480ed2b6 vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=60 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=0000000080b65151 vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=61 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=0000000024e31c5e vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=62 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000332e0385 vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=63 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=000000002754d5da vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=64 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000783320dd vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=65 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=0000000076fe5b64 vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=66 p_offset=0x0 The reason is that kernel always prints the values of the next PT_LOAD instead of the current PT_LOAD. Change it to ensure that we can get the correct debugging information. [ mingo: Amended changelog, capitalized "ELF". ] Signed-off-by: Lianbo Jiang <lijiang@redhat.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Dave Young <dyoung@redhat.com> Link: https://lore.kernel.org/r/20200804044933.1973-4-lijiang@redhat.com
| * kexec: Improve & fix crash_exclude_mem_range() to handle overlapping rangesLianbo Jiang2020-08-071-12/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The crash_exclude_mem_range() function can only handle one memory region a time. It will fail in the case in which the passed in area covers several memory regions. In this case, it will only exclude the first region, then return, but leave the later regions unsolved. E.g in a NEC system with two usable RAM regions inside the low 1M: ... BIOS-e820: [mem 0x0000000000000000-0x000000000003efff] usable BIOS-e820: [mem 0x000000000003f000-0x000000000003ffff] reserved BIOS-e820: [mem 0x0000000000040000-0x000000000009ffff] usable It will only exclude the memory region [0, 0x3efff], the memory region [0x40000, 0x9ffff] will still be added into /proc/vmcore, which may cause the following failure when dumping vmcore: ioremap on RAM at 0x0000000000040000 - 0x0000000000040fff WARNING: CPU: 0 PID: 665 at arch/x86/mm/ioremap.c:186 __ioremap_caller+0x2c7/0x2e0 ... RIP: 0010:__ioremap_caller+0x2c7/0x2e0 ... cp: error reading '/proc/vmcore': Cannot allocate memory kdump: saving vmcore failed In order to fix this bug, let's extend the crash_exclude_mem_range() to handle the overlapping ranges. [ mingo: Amended the changelog. ] Signed-off-by: Lianbo Jiang <lijiang@redhat.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Dave Young <dyoung@redhat.com> Link: https://lore.kernel.org/r/20200804044933.1973-3-lijiang@redhat.com
* | Merge tag 'powerpc-5.9-1' of ↵Linus Torvalds2020-08-071-2/+14
|\ \ | |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: - Add support for (optionally) using queued spinlocks & rwlocks. - Support for a new faster system call ABI using the scv instruction on Power9 or later. - Drop support for the PROT_SAO mmap/mprotect flag as it will be unsupported on Power10 and future processors, leaving us with no way to implement the functionality it requests. This risks breaking userspace, though we believe it is unused in practice. - A bug fix for, and then the removal of, our custom stack expansion checking. We now allow stack expansion up to the rlimit, like other architectures. - Remove the remnants of our (previously disabled) topology update code, which tried to react to NUMA layout changes on virtualised systems, but was prone to crashes and other problems. - Add PMU support for Power10 CPUs. - A change to our signal trampoline so that we don't unbalance the link stack (branch return predictor) in the signal delivery path. - Lots of other cleanups, refactorings, smaller features and so on as usual. Thanks to: Abhishek Goel, Alastair D'Silva, Alexander A. Klimov, Alexey Kardashevskiy, Alistair Popple, Andrew Donnellan, Aneesh Kumar K.V, Anju T Sudhakar, Anton Blanchard, Arnd Bergmann, Athira Rajeev, Balamuruhan S, Bharata B Rao, Bill Wendling, Bin Meng, Cédric Le Goater, Chris Packham, Christophe Leroy, Christoph Hellwig, Daniel Axtens, Dan Williams, David Lamparter, Desnes A. Nunes do Rosario, Erhard F., Finn Thain, Frederic Barrat, Ganesh Goudar, Gautham R. Shenoy, Geoff Levand, Greg Kurz, Gustavo A. R. Silva, Hari Bathini, Harish, Imre Kaloz, Joel Stanley, Joe Perches, John Crispin, Jordan Niethe, Kajol Jain, Kamalesh Babulal, Kees Cook, Laurent Dufour, Leonardo Bras, Li RongQing, Madhavan Srinivasan, Mahesh Salgaonkar, Mark Cave-Ayland, Michal Suchanek, Milton Miller, Mimi Zohar, Murilo Opsfelder Araujo, Nathan Chancellor, Nathan Lynch, Naveen N. Rao, Nayna Jain, Nicholas Piggin, Oliver O'Halloran, Palmer Dabbelt, Pedro Miraglia Franco de Carvalho, Philippe Bergheaud, Pingfan Liu, Pratik Rajesh Sampat, Qian Cai, Qinglang Miao, Randy Dunlap, Ravi Bangoria, Sachin Sant, Sam Bobroff, Sandipan Das, Santosh Sivaraj, Satheesh Rajendran, Shirisha Ganta, Sourabh Jain, Srikar Dronamraju, Stan Johnson, Stephen Rothwell, Thadeu Lima de Souza Cascardo, Thiago Jung Bauermann, Tom Lane, Vaibhav Jain, Vladis Dronov, Wei Yongjun, Wen Xiong, YueHaibing. * tag 'powerpc-5.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (337 commits) selftests/powerpc: Fix pkey syscall redefinitions powerpc: Fix circular dependency between percpu.h and mmu.h powerpc/powernv/sriov: Fix use of uninitialised variable selftests/powerpc: Skip vmx/vsx/tar/etc tests on older CPUs powerpc/40x: Fix assembler warning about r0 powerpc/papr_scm: Add support for fetching nvdimm 'fuel-gauge' metric powerpc/papr_scm: Fetch nvdimm performance stats from PHYP cpuidle: pseries: Fixup exit latency for CEDE(0) cpuidle: pseries: Add function to parse extended CEDE records cpuidle: pseries: Set the latency-hint before entering CEDE selftests/powerpc: Fix online CPU selection powerpc/perf: Consolidate perf_callchain_user_[64|32]() powerpc/pseries/hotplug-cpu: Remove double free in error path powerpc/pseries/mobility: Add pr_debug() for device tree changes powerpc/pseries/mobility: Set pr_fmt() powerpc/cacheinfo: Warn if cache object chain becomes unordered powerpc/cacheinfo: Improve diagnostics about malformed cache lists powerpc/cacheinfo: Use name@unit instead of full DT path in debug messages powerpc/cacheinfo: Set pr_fmt() powerpc: fix function annotations to avoid section mismatch warnings with gcc-10 ...
| * kexec_file: Allow archs to handle special regions while locating memory holeHari Bathini2020-07-291-2/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Some architectures may have special memory regions, within the given memory range, which can't be used for the buffer in a kexec segment. Implement weak arch_kexec_locate_mem_hole() definition which arch code may override, to take care of special regions, while trying to locate a memory hole. Also, add the missing declarations for arch overridable functions and and drop the __weak descriptors in the declarations to avoid non-weak definitions from becoming weak. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Tested-by: Pingfan Liu <piliu@redhat.com> Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com> Acked-by: Dave Young <dyoung@redhat.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/159602273603.575379.17665852963340380839.stgit@hbathini
* | Merge tag 'integrity-v5.9' of ↵Linus Torvalds2020-08-061-1/+1
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity Pull integrity updates from Mimi Zohar: "The nicest change is the IMA policy rule checking. The other changes include allowing the kexec boot cmdline line measure policy rules to be defined in terms of the inode associated with the kexec kernel image, making the IMA_APPRAISE_BOOTPARAM, which governs the IMA appraise mode (log, fix, enforce), a runtime decision based on the secure boot mode of the system, and including errno in the audit log" * tag 'integrity-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity: integrity: remove redundant initialization of variable ret ima: move APPRAISE_BOOTPARAM dependency on ARCH_POLICY to runtime ima: AppArmor satisfies the audit rule requirements ima: Rename internal filter rule functions ima: Support additional conditionals in the KEXEC_CMDLINE hook function ima: Use the common function to detect LSM conditionals in a rule ima: Move comprehensive rule validation checks out of the token parser ima: Use correct type for the args_p member of ima_rule_entry.lsm elements ima: Shallow copy the args_p member of ima_rule_entry.lsm elements ima: Fail rule parsing when appraise_flag=blacklist is unsupportable ima: Fail rule parsing when the KEY_CHECK hook is combined with an invalid cond ima: Fail rule parsing when the KEXEC_CMDLINE hook is combined with an invalid cond ima: Fail rule parsing when buffer hook functions have an invalid action ima: Free the entire rule if it fails to parse ima: Free the entire rule when deleting a list of rules ima: Have the LSM free its audit rule IMA: Add audit log for failure conditions integrity: Add errno field in audit message
| * | ima: Support additional conditionals in the KEXEC_CMDLINE hook functionTyler Hicks2020-07-201-1/+1
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Take the properties of the kexec kernel's inode and the current task ownership into consideration when matching a KEXEC_CMDLINE operation to the rules in the IMA policy. This allows for some uniformity when writing IMA policy rules for KEXEC_KERNEL_CHECK, KEXEC_INITRAMFS_CHECK, and KEXEC_CMDLINE operations. Prior to this patch, it was not possible to write a set of rules like this: dont_measure func=KEXEC_KERNEL_CHECK obj_type=foo_t dont_measure func=KEXEC_INITRAMFS_CHECK obj_type=foo_t dont_measure func=KEXEC_CMDLINE obj_type=foo_t measure func=KEXEC_KERNEL_CHECK measure func=KEXEC_INITRAMFS_CHECK measure func=KEXEC_CMDLINE The inode information associated with the kernel being loaded by a kexec_kernel_load(2) syscall can now be included in the decision to measure or not Additonally, the uid, euid, and subj_* conditionals can also now be used in KEXEC_CMDLINE rules. There was no technical reason as to why those conditionals weren't being considered previously other than ima_match_rules() didn't have a valid inode to use so it immediately bailed out for KEXEC_CMDLINE operations rather than going through the full list of conditional comparisons. Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: kexec@lists.infradead.org Reviewed-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
* / kexec: do not verify the signature without the lockdown or mandatory signatureLianbo Jiang2020-06-261-28/+6
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Signature verification is an important security feature, to protect system from being attacked with a kernel of unknown origin. Kexec rebooting is a way to replace the running kernel, hence need be secured carefully. In the current code of handling signature verification of kexec kernel, the logic is very twisted. It mixes signature verification, IMA signature appraising and kexec lockdown. If there is no KEXEC_SIG_FORCE, kexec kernel image doesn't have one of signature, the supported crypto, and key, we don't think this is wrong, Unless kexec lockdown is executed. IMA is considered as another kind of signature appraising method. If kexec kernel image has signature/crypto/key, it has to go through the signature verification and pass. Otherwise it's seen as verification failure, and won't be loaded. Seems kexec kernel image with an unqualified signature is even worse than those w/o signature at all, this sounds very unreasonable. E.g. If people get a unsigned kernel to load, or a kernel signed with expired key, which one is more dangerous? So, here, let's simplify the logic to improve code readability. If the KEXEC_SIG_FORCE enabled or kexec lockdown enabled, signature verification is mandated. Otherwise, we lift the bar for any kernel image. Link: http://lkml.kernel.org/r/20200602045952.27487-1-lijiang@redhat.com Signed-off-by: Lianbo Jiang <lijiang@redhat.com> Reviewed-by: Jiri Bohac <jbohac@suse.cz> Acked-by: Dave Young <dyoung@redhat.com> Acked-by: Baoquan He <bhe@redhat.com> Cc: James Morris <jmorris@namei.org> Cc: Matthew Garrett <mjg59@google.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kexec_file: don't place kexec images on IORESOURCE_MEM_DRIVER_MANAGEDDavid Hildenbrand2020-06-051-0/+5
| | | | | | | | | | | | | | | | | | | Memory flagged with IORESOURCE_MEM_DRIVER_MANAGED is special - it won't be part of the initial memmap of the kexec kernel and not all memory might be accessible. Don't place any kexec images onto it. Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: Wei Yang <richard.weiyang@gmail.com> Cc: Baoquan He <bhe@redhat.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Dan Williams <dan.j.williams@intel.com> Link: http://lkml.kernel.org/r/20200508084217.9160-4-david@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kexec: add machine_kexec_post_load()Pavel Tatashin2020-01-081-0/+4
| | | | | | | | | | | | It is the same as machine_kexec_prepare(), but is called after segments are loaded. This way, can do processing work with already loaded relocation segments. One such example is arm64: it has to have segments loaded in order to create a page table, but it cannot do it during kexec time, because at that time allocations won't be possible anymore. Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com> Acked-by: Dave Young <dyoung@redhat.com> Signed-off-by: Will Deacon <will@kernel.org>
* kexec: Fix pointer-to-int-cast warningsHelge Deller2019-11-011-2/+2
| | | | | | | | | | | | | | | Fix two pointer-to-int-cast warnings when compiling for the 32-bit parisc platform: kernel/kexec_file.c: In function ‘crash_prepare_elf64_headers’: kernel/kexec_file.c:1307:19: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast] phdr->p_vaddr = (Elf64_Addr)_text; ^ kernel/kexec_file.c:1324:19: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast] phdr->p_vaddr = (unsigned long long) __va(mstart); ^ Signed-off-by: Helge Deller <deller@gmx.de>
* Merge branch 'next-lockdown' of ↵Linus Torvalds2019-09-281-9/+59
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security Pull kernel lockdown mode from James Morris: "This is the latest iteration of the kernel lockdown patchset, from Matthew Garrett, David Howells and others. From the original description: This patchset introduces an optional kernel lockdown feature, intended to strengthen the boundary between UID 0 and the kernel. When enabled, various pieces of kernel functionality are restricted. Applications that rely on low-level access to either hardware or the kernel may cease working as a result - therefore this should not be enabled without appropriate evaluation beforehand. The majority of mainstream distributions have been carrying variants of this patchset for many years now, so there's value in providing a doesn't meet every distribution requirement, but gets us much closer to not requiring external patches. There are two major changes since this was last proposed for mainline: - Separating lockdown from EFI secure boot. Background discussion is covered here: https://lwn.net/Articles/751061/ - Implementation as an LSM, with a default stackable lockdown LSM module. This allows the lockdown feature to be policy-driven, rather than encoding an implicit policy within the mechanism. The new locked_down LSM hook is provided to allow LSMs to make a policy decision around whether kernel functionality that would allow tampering with or examining the runtime state of the kernel should be permitted. The included lockdown LSM provides an implementation with a simple policy intended for general purpose use. This policy provides a coarse level of granularity, controllable via the kernel command line: lockdown={integrity|confidentiality} Enable the kernel lockdown feature. If set to integrity, kernel features that allow userland to modify the running kernel are disabled. If set to confidentiality, kernel features that allow userland to extract confidential information from the kernel are also disabled. This may also be controlled via /sys/kernel/security/lockdown and overriden by kernel configuration. New or existing LSMs may implement finer-grained controls of the lockdown features. Refer to the lockdown_reason documentation in include/linux/security.h for details. The lockdown feature has had signficant design feedback and review across many subsystems. This code has been in linux-next for some weeks, with a few fixes applied along the way. Stephen Rothwell noted that commit 9d1f8be5cf42 ("bpf: Restrict bpf when kernel lockdown is in confidentiality mode") is missing a Signed-off-by from its author. Matthew responded that he is providing this under category (c) of the DCO" * 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (31 commits) kexec: Fix file verification on S390 security: constify some arrays in lockdown LSM lockdown: Print current->comm in restriction messages efi: Restrict efivar_ssdt_load when the kernel is locked down tracefs: Restrict tracefs when the kernel is locked down debugfs: Restrict debugfs when the kernel is locked down kexec: Allow kexec_file() with appropriate IMA policy when locked down lockdown: Lock down perf when in confidentiality mode bpf: Restrict bpf when kernel lockdown is in confidentiality mode lockdown: Lock down tracing and perf kprobes when in confidentiality mode lockdown: Lock down /proc/kcore x86/mmiotrace: Lock down the testmmiotrace module lockdown: Lock down module params that specify hardware parameters (eg. ioport) lockdown: Lock down TIOCSSERIAL lockdown: Prohibit PCMCIA CIS storage when the kernel is locked down acpi: Disable ACPI table override if the kernel is locked down acpi: Ignore acpi_rsdp kernel param when the kernel has been locked down ACPI: Limit access to custom_method when the kernel is locked down x86/msr: Restrict MSR access when the kernel is locked down x86: Lock down IO port access when the kernel is locked down ...
| * kexec: Allow kexec_file() with appropriate IMA policy when locked downMatthew Garrett2019-08-201-1/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Systems in lockdown mode should block the kexec of untrusted kernels. For x86 and ARM we can ensure that a kernel is trustworthy by validating a PE signature, but this isn't possible on other architectures. On those platforms we can use IMA digital signatures instead. Add a function to determine whether IMA has or will verify signatures for a given event type, and if so permit kexec_file() even if the kernel is otherwise locked down. This is restricted to cases where CONFIG_INTEGRITY_TRUSTED_KEYRING is set in order to prevent an attacker from loading additional keys at runtime. Signed-off-by: Matthew Garrett <mjg59@google.com> Acked-by: Mimi Zohar <zohar@linux.ibm.com> Cc: Dmitry Kasatkin <dmitry.kasatkin@gmail.com> Cc: linux-integrity@vger.kernel.org Signed-off-by: James Morris <jmorris@namei.org>
| * kexec_file: Restrict at runtime if the kernel is locked downJiri Bohac2019-08-201-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When KEXEC_SIG is not enabled, kernel should not load images through kexec_file systemcall if the kernel is locked down. [Modified by David Howells to fit with modifications to the previous patch and to return -EPERM if the kernel is locked down for consistency with other lockdowns. Modified by Matthew Garrett to remove the IMA integration, which will be replaced by integrating with the IMA architecture policy patches.] Signed-off-by: Jiri Bohac <jbohac@suse.cz> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Matthew Garrett <mjg59@google.com> cc: kexec@lists.infradead.org Signed-off-by: James Morris <jmorris@namei.org>
| * kexec_file: split KEXEC_VERIFY_SIG into KEXEC_SIG and KEXEC_SIG_FORCEJiri Bohac2019-08-201-9/+51
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is a preparatory patch for kexec_file_load() lockdown. A locked down kernel needs to prevent unsigned kernel images from being loaded with kexec_file_load(). Currently, the only way to force the signature verification is compiling with KEXEC_VERIFY_SIG. This prevents loading usigned images even when the kernel is not locked down at runtime. This patch splits KEXEC_VERIFY_SIG into KEXEC_SIG and KEXEC_SIG_FORCE. Analogous to the MODULE_SIG and MODULE_SIG_FORCE for modules, KEXEC_SIG turns on the signature verification but allows unsigned images to be loaded. KEXEC_SIG_FORCE disallows images without a valid signature. Signed-off-by: Jiri Bohac <jbohac@suse.cz> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Matthew Garrett <mjg59@google.com> cc: kexec@lists.infradead.org Signed-off-by: James Morris <jmorris@namei.org>
* | Merge branch 'next-integrity' of ↵Linus Torvalds2019-07-091-3/+6
|\ \ | |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity Pull integrity updates from Mimi Zohar: "Bug fixes, code clean up, and new features: - IMA policy rules can be defined in terms of LSM labels, making the IMA policy dependent on LSM policy label changes, in particular LSM label deletions. The new environment, in which IMA-appraisal is being used, frequently updates the LSM policy and permits LSM label deletions. - Prevent an mmap'ed shared file opened for write from also being mmap'ed execute. In the long term, making this and other similar changes at the VFS layer would be preferable. - The IMA per policy rule template format support is needed for a couple of new/proposed features (eg. kexec boot command line measurement, appended signatures, and VFS provided file hashes). - Other than the "boot-aggregate" record in the IMA measuremeent list, all other measurements are of file data. Measuring and storing the kexec boot command line in the IMA measurement list is the first buffer based measurement included in the measurement list" * 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity: integrity: Introduce struct evm_xattr ima: Update MAX_TEMPLATE_NAME_LEN to fit largest reasonable definition KEXEC: Call ima_kexec_cmdline to measure the boot command line args IMA: Define a new template field buf IMA: Define a new hook to measure the kexec boot command line arguments IMA: support for per policy rule template formats integrity: Fix __integrity_init_keyring() section mismatch ima: Use designated initializers for struct ima_event_data ima: use the lsm policy update notifier LSM: switch to blocking policy update notifiers x86/ima: fix the Kconfig dependency for IMA_ARCH_POLICY ima: Make arch_policy_entry static ima: prevent a file already mmap'ed write to be mmap'ed execute x86/ima: check EFI SetupMode too
| * KEXEC: Call ima_kexec_cmdline to measure the boot command line argsPrakhar Srivastava2019-06-301-3/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | During soft reboot(kexec_file_load) boot command line arguments are not measured. Call ima hook ima_kexec_cmdline to measure the boot command line arguments into IMA measurement list. - call ima_kexec_cmdline from kexec_file_load. - move the call ima_add_kexec_buffer after the cmdline args have been measured. Signed-off-by: Prakhar Srivastava <prsriva02@gmail.com> Reviewed-by: James Morris <jamorris@linux.microsoft.com> Acked-by: Dave Young <dyoung@redhat.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
* | treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 230Thomas Gleixner2019-06-191-3/+1
|/ | | | | | | | | | | | | | | | | | | | | | | | Based on 2 normalized pattern(s): this source code is licensed under the gnu general public license version 2 see the file copying for more details this source code is licensed under general public license version 2 see extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 52 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190602204653.449021192@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* mm: memblock: make keeping memblock memory opt-in rather than opt-outMike Rapoport2019-05-141-8/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Most architectures do not need the memblock memory after the page allocator is initialized, but only few enable ARCH_DISCARD_MEMBLOCK in the arch Kconfig. Replacing ARCH_DISCARD_MEMBLOCK with ARCH_KEEP_MEMBLOCK and inverting the logic makes it clear which architectures actually use memblock after system initialization and skips the necessity to add ARCH_DISCARD_MEMBLOCK to the architectures that are still missing that option. Link: http://lkml.kernel.org/r/1556102150-32517-1-git-send-email-rppt@linux.ibm.com Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc) Cc: Russell King <linux@armlinux.org.uk> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Richard Kuo <rkuo@codeaurora.org> Cc: Tony Luck <tony.luck@intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Paul Burton <paul.burton@mips.com> Cc: James Hogan <jhogan@kernel.org> Cc: Ley Foon Tan <lftan@altera.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Rich Felker <dalias@libc.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Eric Biederman <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* crypto: shash - remove shash_desc::flagsEric Biggers2019-04-251-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | The flags field in 'struct shash_desc' never actually does anything. The only ostensibly supported flag is CRYPTO_TFM_REQ_MAY_SLEEP. However, no shash algorithm ever sleeps, making this flag a no-op. With this being the case, inevitably some users who can't sleep wrongly pass MAY_SLEEP. These would all need to be fixed if any shash algorithm actually started sleeping. For example, the shash_ahash_*() functions, which wrap a shash algorithm with the ahash API, pass through MAY_SLEEP from the ahash API to the shash API. However, the shash functions are called under kmap_atomic(), so actually they're assumed to never sleep. Even if it turns out that some users do need preemption points while hashing large buffers, we could easily provide a helper function crypto_shash_update_large() which divides the data into smaller chunks and calls crypto_shash_update() and cond_resched() for each chunk. It's not necessary to have a flag in 'struct shash_desc', nor is it necessary to make individual shash algorithms aware of this at all. Therefore, remove shash_desc::flags, and document that the crypto_shash_*() functions can be called from any context. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* kexec_file: kexec_walk_memblock() only walks a dedicated region at kdumpAKASHI Takahiro2018-12-061-3/+6
| | | | | | | | | | | | | | In kdump case, there exists only one dedicated memblock region as usable memory (crashk_res). With this patch, kexec_walk_memblock() runs a given callback function on this region. Cosmetic change: 0 to MEMBLOCK_NONE at for_each_free_mem_range*() Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> Acked-by: Dave Young <dyoung@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Baoquan He <bhe@redhat.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
* powerpc, kexec_file: factor out memblock-based arch_kexec_walk_mem()AKASHI Takahiro2018-12-061-4/+57
| | | | | | | | | | | | | | | | | | | | | | | | Memblock list is another source for usable system memory layout. So move powerpc's arch_kexec_walk_mem() to common code so that other memblock-based architectures, particularly arm64, can also utilise it. A moved function is now renamed to kexec_walk_memblock() and integrated into kexec_locate_mem_hole(), which will now be usable for all architectures with no need for overriding arch_kexec_walk_mem(). With this change, arch_kexec_walk_mem() need no longer be a weak function, and was now renamed to kexec_walk_resources(). Since powerpc doesn't support kdump in its kexec_file_load(), the current kexec_walk_memblock() won't work for kdump either in this form, this will be fixed in the next patch. Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Acked-by: Dave Young <dyoung@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Baoquan He <bhe@redhat.com> Acked-by: James Morse <james.morse@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
* s390, kexec_file: drop arch_kexec_mem_walk()AKASHI Takahiro2018-12-061-0/+4
| | | | | | | | | | | | | | | | | | | | Since s390 already knows where to locate buffers, calling arch_kexec_mem_walk() has no sense. So we can just drop it as kbuf->mem indicates this while all other architectures sets it to 0 initially. This change is a preparatory work for the next patch, where all the variant memory walks, either on system resource or memblock, will be put in one common place so that it will satisfy all the architectures' need. Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> Reviewed-by: Philipp Rudo <prudo@linux.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Dave Young <dyoung@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Baoquan He <bhe@redhat.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
* kexec_file: make kexec_image_post_load_cleanup_default() globalAKASHI Takahiro2018-12-061-1/+1
| | | | | | | | | | | | Change this function from static to global so that arm64 can implement its own arch_kimage_file_post_load_cleanup() later using kexec_image_post_load_cleanup_default(). Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> Acked-by: Dave Young <dyoung@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Baoquan He <bhe@redhat.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
* kernel/kexec_file.c: remove some duplicated includeszhong jiang2018-11-031-2/+0
| | | | | | | | | | | | | We include kexec.h and slab.h twice in kexec_file.c. It's unnecessary. hence just remove them. Link: http://lkml.kernel.org/r/1537498098-19171-1-git-send-email-zhongjiang@huawei.com Signed-off-by: zhong jiang <zhongjiang@huawei.com> Reviewed-by: Bhupesh Sharma <bhsharma@redhat.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Baoquan He <bhe@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* treewide: Use array_size() in vzalloc()Kees Cook2018-06-131-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The vzalloc() function has no 2-factor argument form, so multiplication factors need to be wrapped in array_size(). This patch replaces cases of: vzalloc(a * b) with: vzalloc(array_size(a, b)) as well as handling cases of: vzalloc(a * b * c) with: vzalloc(array3_size(a, b, c)) This does, however, attempt to ignore constant size factors like: vzalloc(4 * 1024) though any constants defined via macros get caught up in the conversion. Any factors with a sizeof() of "unsigned char", "char", and "u8" were dropped, since they're redundant. The Coccinelle script used for this was: // Fix redundant parens around sizeof(). @@ type TYPE; expression THING, E; @@ ( vzalloc( - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | vzalloc( - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression COUNT; typedef u8; typedef __u8; @@ ( vzalloc( - sizeof(u8) * (COUNT) + COUNT , ...) | vzalloc( - sizeof(__u8) * (COUNT) + COUNT , ...) | vzalloc( - sizeof(char) * (COUNT) + COUNT , ...) | vzalloc( - sizeof(unsigned char) * (COUNT) + COUNT , ...) | vzalloc( - sizeof(u8) * COUNT + COUNT , ...) | vzalloc( - sizeof(__u8) * COUNT + COUNT , ...) | vzalloc( - sizeof(char) * COUNT + COUNT , ...) | vzalloc( - sizeof(unsigned char) * COUNT + COUNT , ...) ) // 2-factor product with sizeof(type/expression) and identifier or constant. @@ type TYPE; expression THING; identifier COUNT_ID; constant COUNT_CONST; @@ ( vzalloc( - sizeof(TYPE) * (COUNT_ID) + array_size(COUNT_ID, sizeof(TYPE)) , ...) | vzalloc( - sizeof(TYPE) * COUNT_ID + array_size(COUNT_ID, sizeof(TYPE)) , ...) | vzalloc( - sizeof(TYPE) * (COUNT_CONST) + array_size(COUNT_CONST, sizeof(TYPE)) , ...) | vzalloc( - sizeof(TYPE) * COUNT_CONST + array_size(COUNT_CONST, sizeof(TYPE)) , ...) | vzalloc( - sizeof(THING) * (COUNT_ID) + array_size(COUNT_ID, sizeof(THING)) , ...) | vzalloc( - sizeof(THING) * COUNT_ID + array_size(COUNT_ID, sizeof(THING)) , ...) | vzalloc( - sizeof(THING) * (COUNT_CONST) + array_size(COUNT_CONST, sizeof(THING)) , ...) | vzalloc( - sizeof(THING) * COUNT_CONST + array_size(COUNT_CONST, sizeof(THING)) , ...) ) // 2-factor product, only identifiers. @@ identifier SIZE, COUNT; @@ vzalloc( - SIZE * COUNT + array_size(COUNT, SIZE) , ...) // 3-factor product with 1 sizeof(type) or sizeof(expression), with // redundant parens removed. @@ expression THING; identifier STRIDE, COUNT; type TYPE; @@ ( vzalloc( - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | vzalloc( - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | vzalloc( - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | vzalloc( - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | vzalloc( - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | vzalloc( - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | vzalloc( - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | vzalloc( - sizeof(THING) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) ) // 3-factor product with 2 sizeof(variable), with redundant parens removed. @@ expression THING1, THING2; identifier COUNT; type TYPE1, TYPE2; @@ ( vzalloc( - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | vzalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | vzalloc( - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | vzalloc( - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | vzalloc( - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | vzalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) ) // 3-factor product, only identifiers, with redundant parens removed. @@ identifier STRIDE, SIZE, COUNT; @@ ( vzalloc( - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | vzalloc( - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | vzalloc( - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | vzalloc( - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | vzalloc( - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | vzalloc( - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | vzalloc( - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | vzalloc( - COUNT * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) ) // Any remaining multi-factor products, first at least 3-factor products // when they're not all constants... @@ expression E1, E2, E3; constant C1, C2, C3; @@ ( vzalloc(C1 * C2 * C3, ...) | vzalloc( - E1 * E2 * E3 + array3_size(E1, E2, E3) , ...) ) // And then all remaining 2 factors products when they're not all constants. @@ expression E1, E2; constant C1, C2; @@ ( vzalloc(C1 * C2, ...) | vzalloc( - E1 * E2 + array_size(E1, E2) , ...) ) Signed-off-by: Kees Cook <keescook@chromium.org>
* kernel/kexec_file.c: allow archs to set purgatory load addressPhilipp Rudo2018-04-141-13/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For s390 new kernels are loaded to fixed addresses in memory before they are booted. With the current code this is a problem as it assumes the kernel will be loaded to an 'arbitrary' address. In particular, kexec_locate_mem_hole searches for a large enough memory region and sets the load address (kexec_bufer->mem) to it. Luckily there is a simple workaround for this problem. By returning 1 in arch_kexec_walk_mem, kexec_locate_mem_hole is turned off. This allows the architecture to set kbuf->mem by hand. While the trick works fine for the kernel it does not for the purgatory as here the architectures don't have access to its kexec_buffer. Give architectures access to the purgatories kexec_buffer by changing kexec_load_purgatory to take a pointer to it. With this change architectures have access to the buffer and can edit it as they need. A nice side effect of this change is that we can get rid of the purgatory_info->purgatory_load_address field. As now the information stored there can directly be accessed from kbuf->mem. Link: http://lkml.kernel.org/r/20180321112751.22196-11-prudo@linux.vnet.ibm.com Signed-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com> Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Acked-by: Dave Young <dyoung@redhat.com> Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kernel/kexec_file.c: remove mis-use of sh_offset field during purgatory loadPhilipp Rudo2018-04-141-30/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | The current code uses the sh_offset field in purgatory_info->sechdrs to store a pointer to the current load address of the section. Depending whether the section will be loaded or not this is either a pointer into purgatory_info->purgatory_buf or kexec_purgatory. This is not only a violation of the ELF standard but also makes the code very hard to understand as you cannot tell if the memory you are using is read-only or not. Remove this misuse and store the offset of the section in pugaroty_info->purgatory_buf in sh_offset. Link: http://lkml.kernel.org/r/20180321112751.22196-10-prudo@linux.vnet.ibm.com Signed-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com> Acked-by: Dave Young <dyoung@redhat.com> Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kernel/kexec_file.c: remove unneeded variables in kexec_purgatory_setup_sechdrsPhilipp Rudo2018-04-141-22/+12
| | | | | | | | | | | | | | | | | | | | The main loop currently uses quite a lot of variables to update the section headers. Some of them are unnecessary. So clean them up a little. Link: http://lkml.kernel.org/r/20180321112751.22196-9-prudo@linux.vnet.ibm.com Signed-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com> Acked-by: Dave Young <dyoung@redhat.com> Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kernel/kexec_file.c: remove unneeded for-loop in kexec_purgatory_setup_sechdrsPhilipp Rudo2018-04-141-46/+30
| | | | | | | | | | | | | | | | | | | | | | | | To update the entry point there is an extra loop over all section headers although this can be done in the main loop. So move it there and eliminate the extra loop and variable to store the 'entry section index'. Also, in the main loop, move the usual case, i.e. non-bss section, out of the extra if-block. Link: http://lkml.kernel.org/r/20180321112751.22196-8-prudo@linux.vnet.ibm.com Signed-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com> Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Acked-by: Dave Young <dyoung@redhat.com> Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kernel/kexec_file.c: split up __kexec_load_puragoryPhilipp Rudo2018-04-141-97/+103
| | | | | | | | | | | | | | | | | | | | | | | | | When inspecting __kexec_load_purgatory you find that it has two tasks 1) setting up the kexec_buffer for the new kernel and, 2) setting up pi->sechdrs for the final load address. The two tasks are independent of each other. To improve readability split up __kexec_load_purgatory into two functions, one for each task, and call them directly from kexec_load_purgatory. Link: http://lkml.kernel.org/r/20180321112751.22196-7-prudo@linux.vnet.ibm.com Signed-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com> Acked-by: Dave Young <dyoung@redhat.com> Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kernel/kexec_file.c: use read-only sections in arch_kexec_apply_relocations*Philipp Rudo2018-04-141-21/+42
| | | | | | | | | | | | | | | | | | | | | | | | | | When the relocations are applied to the purgatory only the section the relocations are applied to is writable. The other sections, i.e. the symtab and .rel/.rela, are in read-only kexec_purgatory. Highlight this by marking the corresponding variables as 'const'. While at it also change the signatures of arch_kexec_apply_relocations* to take section pointers instead of just the index of the relocation section. This removes the second lookup and sanity check of the sections in arch code. Link: http://lkml.kernel.org/r/20180321112751.22196-6-prudo@linux.vnet.ibm.com Signed-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com> Acked-by: Dave Young <dyoung@redhat.com> Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kernel/kexec_file.c: search symbols in read-only kexec_purgatoryPhilipp Rudo2018-04-141-16/+22
| | | | | | | | | | | | | | | | | | | | The stripped purgatory does not contain a symtab. So when looking for symbols this is done in read-only kexec_purgatory. Highlight this by marking the corresponding variables as 'const'. Link: http://lkml.kernel.org/r/20180321112751.22196-5-prudo@linux.vnet.ibm.com Signed-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com> Acked-by: Dave Young <dyoung@redhat.com> Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kernel/kexec_file.c: make purgatory_info->ehdr constPhilipp Rudo2018-04-141-2/+2
| | | | | | | | | | | | | | | | | | | | | The kexec_purgatory buffer is read-only. Thus all pointers into kexec_purgatory are read-only, too. Point this out by explicitly marking purgatory_info->ehdr as 'const' and update the comments in purgatory_info. Link: http://lkml.kernel.org/r/20180321112751.22196-4-prudo@linux.vnet.ibm.com Signed-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com> Acked-by: Dave Young <dyoung@redhat.com> Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kernel/kexec_file.c: remove checks in kexec_purgatory_loadPhilipp Rudo2018-04-141-14/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Before the purgatory is loaded several checks are done whether the ELF file in kexec_purgatory is valid or not. These checks are incomplete. For example they don't check for the total size of the sections defined in the section header table or if the entry point actually points into the purgatory. On the other hand the purgatory, although an ELF file on its own, is part of the kernel. Thus not trusting the purgatory means not trusting the kernel build itself. So remove all validity checks on the purgatory and just trust the kernel build. Link: http://lkml.kernel.org/r/20180321112751.22196-3-prudo@linux.vnet.ibm.com Signed-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com> Acked-by: Dave Young <dyoung@redhat.com> Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kexec_file, x86: move re-factored code to generic sideAKASHI Takahiro2018-04-141-0/+175
| | | | | | | | | | | | | | | | In the previous patches, commonly-used routines, exclude_mem_range() and prepare_elf64_headers(), were carved out. Now place them in kexec common code. A prefix "crash_" is given to each of their names to avoid possible name collisions. Link: http://lkml.kernel.org/r/20180306102303.9063-8-takahiro.akashi@linaro.org Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> Acked-by: Dave Young <dyoung@redhat.com> Tested-by: Dave Young <dyoung@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Baoquan He <bhe@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kexec_file,x86,powerpc: factor out kexec_file_ops functionsAKASHI Takahiro2018-04-141-4/+56
| | | | | | | | | | | | | | | | | | As arch_kexec_kernel_image_{probe,load}(), arch_kimage_file_post_load_cleanup() and arch_kexec_kernel_verify_sig() are almost duplicated among architectures, they can be commonalized with an architecture-defined kexec_file_ops array. So let's factor them out. Link: http://lkml.kernel.org/r/20180306102303.9063-3-takahiro.akashi@linaro.org Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> Acked-by: Dave Young <dyoung@redhat.com> Tested-by: Dave Young <dyoung@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Baoquan He <bhe@redhat.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kexec_file: make use of purgatory optionalAKASHI Takahiro2018-04-141-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Patch series "kexec_file, x86, powerpc: refactoring for other architecutres", v2. This is a preparatory patchset for adding kexec_file support on arm64. It was originally included in a arm64 patch set[1], but Philipp is also working on their kexec_file support on s390[2] and some changes are now conflicting. So these common parts were extracted and put into a separate patch set for better integration. What's more, my original patch#4 was split into a few small chunks for easier review after Dave's comment. As such, the resulting code is basically identical with my original, and the only *visible* differences are: - renaming of _kexec_kernel_image_probe() and _kimage_file_post_load_cleanup() - change one of types of arguments at prepare_elf64_headers() Those, unfortunately, require a couple of trivial changes on the rest (#1, #6 to #13) of my arm64 kexec_file patch set[1]. Patch #1 allows making a use of purgatory optional, particularly useful for arm64. Patch #2 commonalizes arch_kexec_kernel_{image_probe, image_load, verify_sig}() and arch_kimage_file_post_load_cleanup() across architectures. Patches #3-#7 are also intended to generalize parse_elf64_headers(), along with exclude_mem_range(), to be made best re-use of. [1] http://lists.infradead.org/pipermail/linux-arm-kernel/2018-February/561182.html [2] http://lkml.iu.edu//hypermail/linux/kernel/1802.1/02596.html This patch (of 7): On arm64, crash dump kernel's usable memory is protected by *unmapping* it from kernel virtual space unlike other architectures where the region is just made read-only. It is highly unlikely that the region is accidentally corrupted and this observation rationalizes that digest check code can also be dropped from purgatory. The resulting code is so simple as it doesn't require a bit ugly re-linking/relocation stuff, i.e. arch_kexec_apply_relocations_add(). Please see: http://lists.infradead.org/pipermail/linux-arm-kernel/2017-December/545428.html All that the purgatory does is to shuffle arguments and jump into a new kernel, while we still need to have some space for a hash value (purgatory_sha256_digest) which is never checked against. As such, it doesn't make sense to have trampline code between old kernel and new kernel on arm64. This patch introduces a new configuration, ARCH_HAS_KEXEC_PURGATORY, and allows related code to be compiled in only if necessary. [takahiro.akashi@linaro.org: fix trivial screwup] Link: http://lkml.kernel.org/r/20180309093346.GF25863@linaro.org Link: http://lkml.kernel.org/r/20180306102303.9063-2-takahiro.akashi@linaro.org Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> Acked-by: Dave Young <dyoung@redhat.com> Tested-by: Dave Young <dyoung@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Baoquan He <bhe@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* resource: Provide resource struct in resource walk callbackTom Lendacky2017-11-071-2/+3
| | | | | | | | | | | | | | | | | | | | | In preperation for a new function that will need additional resource information during the resource walk, update the resource walk callback to pass the resource structure. Since the current callback start and end arguments are pulled from the resource structure, the callback functions can obtain them from the resource structure directly. Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by: Brijesh Singh <brijesh.singh@amd.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Borislav Petkov <bp@suse.de> Tested-by: Borislav Petkov <bp@suse.de> Cc: kvm@vger.kernel.org Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Borislav Petkov <bp@alien8.de> Cc: linuxppc-dev@lists.ozlabs.org Link: https://lkml.kernel.org/r/20171020143059.3291-10-brijesh.singh@amd.com
* kexec_file: adjust declaration of kexec_purgatoryKees Cook2017-07-131-7/+0
| | | | | | | | | | | | | | | | | Defining kexec_purgatory as a zero-length char array upsets compile time size checking. Since this is built on a per-arch basis, define it as an unsized char array (like is done for other similar things, e.g. linker sections). This silences the warning generated by the future CONFIG_FORTIFY_SOURCE, which did not like the memcmp() of a "0 byte" array. This drops the __weak and uses an extern instead, since both users define kexec_purgatory. Link: http://lkml.kernel.org/r/1497903987-21002-4-git-send-email-keescook@chromium.org Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Daniel Micay <danielmicay@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kdump: protect vmcoreinfo data under the crash memoryXunlei Pang2017-07-131-0/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently vmcoreinfo data is updated at boot time subsys_initcall(), it has the risk of being modified by some wrong code during system is running. As a result, vmcore dumped may contain the wrong vmcoreinfo. Later on, when using "crash", "makedumpfile", etc utility to parse this vmcore, we probably will get "Segmentation fault" or other unexpected errors. E.g. 1) wrong code overwrites vmcoreinfo_data; 2) further crashes the system; 3) trigger kdump, then we obviously will fail to recognize the crash context correctly due to the corrupted vmcoreinfo. Now except for vmcoreinfo, all the crash data is well protected(including the cpu note which is fully updated in the crash path, thus its correctness is guaranteed). Given that vmcoreinfo data is a large chunk prepared for kdump, we better protect it as well. To solve this, we relocate and copy vmcoreinfo_data to the crash memory when kdump is loading via kexec syscalls. Because the whole crash memory will be protected by existing arch_kexec_protect_crashkres() mechanism, we naturally protect vmcoreinfo_data from write(even read) access under kernel direct mapping after kdump is loaded. Since kdump is usually loaded at the very early stage after boot, we can trust the correctness of the vmcoreinfo data copied. On the other hand, we still need to operate the vmcoreinfo safe copy when crash happens to generate vmcoreinfo_note again, we rely on vmap() to map out a new kernel virtual address and update to use this new one instead in the following crash_save_vmcoreinfo(). BTW, we do not touch vmcoreinfo_note, because it will be fully updated using the protected vmcoreinfo_data after crash which is surely correct just like the cpu crash note. Link: http://lkml.kernel.org/r/1493281021-20737-3-git-send-email-xlpang@redhat.com Signed-off-by: Xunlei Pang <xlpang@redhat.com> Tested-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Dave Young <dyoung@redhat.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Hari Bathini <hbathini@linux.vnet.ibm.com> Cc: Juergen Gross <jgross@suse.com> Cc: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kimage_file_prepare_segments(): don't open-code memdup_user()Al Viro2017-06-301-10/+4
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* kexec, x86/purgatory: Unbreak it and clean it upThomas Gleixner2017-03-101-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The purgatory code defines global variables which are referenced via a symbol lookup in the kexec code (core and arch). A recent commit addressing sparse warnings made these static and thereby broke kexec_file. Why did this happen? Simply because the whole machinery is undocumented and lacks any form of forward declarations. The variable names are unspecific and lack a prefix, so adding forward declarations creates shadow variables in the core code. Aside of that the code relies on magic constants and duplicate struct definitions with no way to ensure that these things stay in sync. The section placement of the purgatory variables happened by chance and not by design. Unbreak kexec and cleanup the mess: - Add proper forward declarations and document the usage - Use common struct definition - Use the proper common defines instead of magic constants - Add a purgatory_ prefix to have a proper name space - Use ARRAY_SIZE() instead of a homebrewn reimplementation - Add proper sections to the purgatory variables [ From Mike ] Fixes: 72042a8c7b01 ("x86/purgatory: Make functions and variables static") Reported-by: Mike Galbraith <<efault@gmx.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Nicholas Mc Guire <der.herr@hofr.at> Cc: Borislav Petkov <bp@alien8.de> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: "Tobin C. Harding" <me@tobin.cc> Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1703101315140.3681@nanos Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* ima: on soft reboot, save the measurement listMimi Zohar2016-12-201-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | The TPM PCRs are only reset on a hard reboot. In order to validate a TPM's quote after a soft reboot (eg. kexec -e), the IMA measurement list of the running kernel must be saved and restored on boot. This patch uses the kexec buffer passing mechanism to pass the serialized IMA binary_runtime_measurements to the next kernel. Link: http://lkml.kernel.org/r/1480554346-29071-7-git-send-email-zohar@linux.vnet.ibm.com Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Acked-by: Dmitry Kasatkin <dmitry.kasatkin@gmail.com> Cc: Andreas Steffen <andreas.steffen@strongswan.org> Cc: Josh Sklar <sklar@linux.vnet.ibm.com> Cc: Dave Young <dyoung@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Baoquan He <bhe@redhat.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Stewart Smith <stewart@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kexec_file: Factor out kexec_locate_mem_hole from kexec_add_buffer.Thiago Jung Bauermann2016-11-301-5/+20
| | | | | | | | | kexec_locate_mem_hole will be used by the PowerPC kexec_file_load implementation to find free memory for the purgatory stack. Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Acked-by: Dave Young <dyoung@redhat.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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