kernel/linux.git/fs/pstore, branch linux-6.0.y

pstore/zone: Use GFP_ATOMIC to allocate zone buffer

2023-01-04T10:26:28+00:00

commit 99b3b837855b987563bcfb397cf9ddd88262814b upstream. There is a case found when triggering a panic_on_oom, pstore fails to dump kmsg. Because psz_kmsg_write_record can't get the new buffer. Handle this by using GFP_ATOMIC to allocate a buffer at lower watermark. Signed-off-by: Qiujun Huang Fixes: 335426c6dcdd ("pstore/zone: Provide way to skip "broken" zone for MTD devices") Cc: WeiXiong Liao Cc: stable@vger.kernel.org Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/CAJRQjofRCF7wjrYmw3D7zd5QZnwHQq+F8U-mJDJ6NZ4bddYdLA@mail.gmail.com Signed-off-by: Greg Kroah-Hartman

pstore: Properly assign mem_type property

2023-01-04T10:26:28+00:00

commit beca3e311a49cd3c55a056096531737d7afa4361 upstream. If mem-type is specified in the device tree it would end up overriding the record_size field instead of populating mem_type. As record_size is currently parsed after the improper assignment with default size 0 it continued to work as expected regardless of the value found in the device tree. Simply changing the target field of the struct is enough to get mem-type working as expected. Fixes: 9d843e8fafc7 ("pstore: Add mem_type property DT parsing support") Cc: stable@vger.kernel.org Signed-off-by: Luca Stefani Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/20221222131049.286288-1-luca@osomprivacy.com Signed-off-by: Greg Kroah-Hartman

pstore: Make sure CONFIG_PSTORE_PMSG selects CONFIG_RT_MUTEXES

2022-12-31T12:26:50+00:00

[ Upstream commit 2f4fec5943407318b9523f01ce1f5d668c028332 ] In commit 76d62f24db07 ("pstore: Switch pmsg_lock to an rt_mutex to avoid priority inversion") I changed a lock to an rt_mutex. However, its possible that CONFIG_RT_MUTEXES is not enabled, which then results in a build failure, as the 0day bot detected: https://lore.kernel.org/linux-mm/202212211244.TwzWZD3H-lkp@intel.com/ Thus this patch changes CONFIG_PSTORE_PMSG to select CONFIG_RT_MUTEXES, which ensures the build will not fail. Cc: Wei Wang Cc: Midas Chien Cc: Connor O'Brien Cc: Kees Cook Cc: Anton Vorontsov Cc: Colin Cross Cc: Tony Luck Cc: kernel test robot Cc: kernel-team@android.com Fixes: 76d62f24db07 ("pstore: Switch pmsg_lock to an rt_mutex to avoid priority inversion") Reported-by: kernel test robot Signed-off-by: John Stultz Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/20221221051855.15761-1-jstultz@google.com Signed-off-by: Sasha Levin

pstore: Switch pmsg_lock to an rt_mutex to avoid priority inversion

2022-12-31T12:26:50+00:00

[ Upstream commit 76d62f24db07f22ccf9bc18ca793c27d4ebef721 ] Wei Wang reported seeing priority inversion caused latencies caused by contention on pmsg_lock, and suggested it be switched to a rt_mutex. I was initially hesitant this would help, as the tasks in that trace all seemed to be SCHED_NORMAL, so the benefit would be limited to only nice boosting. However, another similar issue was raised where the priority inversion was seen did involve a blocked RT task so it is clear this would be helpful in that case. Cc: Wei Wang Cc: Midas Chien Cc: Connor O'Brien Cc: Kees Cook Cc: Anton Vorontsov Cc: Colin Cross Cc: Tony Luck Cc: kernel-team@android.com Fixes: 9d5438f462ab ("pstore: Add pmsg - user-space accessible pstore object") Reported-by: Wei Wang Signed-off-by: John Stultz Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/20221214231834.3711880-1-jstultz@google.com Signed-off-by: Sasha Levin

pstore: Avoid kcore oops by vmap()ing with VM_IOREMAP

2022-12-31T12:25:40+00:00

[ Upstream commit e6b842741b4f39007215fd7e545cb55aa3d358a2 ] An oops can be induced by running 'cat /proc/kcore > /dev/null' on devices using pstore with the ram backend because kmap_atomic() assumes lowmem pages are accessible with __va(). Unable to handle kernel paging request at virtual address ffffff807ff2b000 Mem abort info: ESR = 0x96000006 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 FSC = 0x06: level 2 translation fault Data abort info: ISV = 0, ISS = 0x00000006 CM = 0, WnR = 0 swapper pgtable: 4k pages, 39-bit VAs, pgdp=0000000081d87000 [ffffff807ff2b000] pgd=180000017fe18003, p4d=180000017fe18003, pud=180000017fe18003, pmd=0000000000000000 Internal error: Oops: 96000006 [#1] PREEMPT SMP Modules linked in: dm_integrity CPU: 7 PID: 21179 Comm: perf Not tainted 5.15.67-10882-ge4eb2eb988cd #1 baa443fb8e8477896a370b31a821eb2009f9bfba Hardware name: Google Lazor (rev3 - 8) (DT) pstate: a0400009 (NzCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : __memcpy+0x110/0x260 lr : vread+0x194/0x294 sp : ffffffc013ee39d0 x29: ffffffc013ee39f0 x28: 0000000000001000 x27: ffffff807ff2b000 x26: 0000000000001000 x25: ffffffc0085a2000 x24: ffffff802d4b3000 x23: ffffff80f8a60000 x22: ffffff802d4b3000 x21: ffffffc0085a2000 x20: ffffff8080b7bc68 x19: 0000000000001000 x18: 0000000000000000 x17: 0000000000000000 x16: 0000000000000000 x15: ffffffd3073f2e60 x14: ffffffffad588000 x13: 0000000000000000 x12: 0000000000000001 x11: 00000000000001a2 x10: 00680000fff2bf0b x9 : 03fffffff807ff2b x8 : 0000000000000001 x7 : 0000000000000000 x6 : 0000000000000000 x5 : ffffff802d4b4000 x4 : ffffff807ff2c000 x3 : ffffffc013ee3a78 x2 : 0000000000001000 x1 : ffffff807ff2b000 x0 : ffffff802d4b3000 Call trace: __memcpy+0x110/0x260 read_kcore+0x584/0x778 proc_reg_read+0xb4/0xe4 During early boot, memblock reserves the pages for the ramoops reserved memory node in DT that would otherwise be part of the direct lowmem mapping. Pstore's ram backend reuses those reserved pages to change the memory type (writeback or non-cached) by passing the pages to vmap() (see pfn_to_page() usage in persistent_ram_vmap() for more details) with specific flags. When read_kcore() starts iterating over the vmalloc region, it runs over the virtual address that vmap() returned for ramoops. In aligned_vread() the virtual address is passed to vmalloc_to_page() which returns the page struct for the reserved lowmem area. That lowmem page is passed to kmap_atomic(), which effectively calls page_to_virt() that assumes a lowmem page struct must be directly accessible with __va() and friends. These pages are mapped via vmap() though, and the lowmem mapping was never made, so accessing them via the lowmem virtual address oopses like above. Let's side-step this problem by passing VM_IOREMAP to vmap(). This will tell vread() to not include the ramoops region in the kcore. Instead the area will look like a bunch of zeros. The alternative is to teach kmap() about vmalloc areas that intersect with lowmem. Presumably such a change isn't a one-liner, and there isn't much interest in inspecting the ramoops region in kcore files anyway, so the most expedient route is taken for now. Cc: Brian Geffon Cc: Mike Rapoport Cc: Andrew Morton Fixes: 404a6043385d ("staging: android: persistent_ram: handle reserving and mapping memory") Signed-off-by: Stephen Boyd Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/20221205233136.3420802-1-swboyd@chromium.org Signed-off-by: Sasha Levin

pstore/ram: Fix error return code in ramoops_probe()

2022-12-31T12:25:40+00:00

[ Upstream commit e1fce564900f8734edf15b87f028c57e14f6e28d ] In the if (dev_of_node(dev) && !pdata) path, the "err" may be assigned a value of 0, so the error return code -EINVAL may be incorrectly set to 0. To fix set valid return code before calling to goto. Fixes: 35da60941e44 ("pstore/ram: add Device Tree bindings") Signed-off-by: Wang Yufen Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/1669969374-46582-1-git-send-email-wangyufen@huawei.com Signed-off-by: Sasha Levin

Revert "pstore: migrate to crypto acomp interface"

2022-09-30T15:16:06+00:00

This reverts commit e4f0a7ec586b7644107839f5394fb685cf1aadcc. When using this new interface, both efi_pstore and ramoops backends are unable to properly decompress dmesg if using zstd, lz4 and lzo algorithms (and maybe more). It does succeed with deflate though. The message observed in the kernel log is: [2.328828] pstore: crypto_acomp_decompress failed, ret = -22! The pstore infrastructure is able to collect the dmesg with both backends tested, but since decompression fails it's unreadable. With this revert everything is back to normal. Fixes: e4f0a7ec586b ("pstore: migrate to crypto acomp interface") Cc: Ard Biesheuvel Signed-off-by: Guilherme G. Piccoli Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/20220929215515.276486-1-gpiccoli@igalia.com

Merge tag 'efi-next-for-v5.20' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi

2022-08-03T21:38:02+00:00

Pull EFI updates from Ard Biesheuvel: - Enable mirrored memory for arm64 - Fix up several abuses of the efivar API - Refactor the efivar API in preparation for moving the 'business logic' part of it into efivarfs - Enable ACPI PRM on arm64 * tag 'efi-next-for-v5.20' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi: (24 commits) ACPI: Move PRM config option under the main ACPI config ACPI: Enable Platform Runtime Mechanism(PRM) support on ARM64 ACPI: PRM: Change handler_addr type to void pointer efi: Simplify arch_efi_call_virt() macro drivers: fix typo in firmware/efi/memmap.c efi: vars: Drop __efivar_entry_iter() helper which is no longer used efi: vars: Use locking version to iterate over efivars linked lists efi: pstore: Omit efivars caching EFI varstore access layer efi: vars: Add thin wrapper around EFI get/set variable interface efi: vars: Don't drop lock in the middle of efivar_init() pstore: Add priv field to pstore_record for backend specific use Input: applespi - avoid efivars API and invoke EFI services directly selftests/kexec: remove broken EFI_VARS secure boot fallback check brcmfmac: Switch to appropriate helper to load EFI variable contents iwlwifi: Switch to proper EFI variable store interface media: atomisp_gmin_platform: stop abusing efivar API efi: efibc: avoid efivar API for setting variables efi: avoid efivars layer when loading SSDTs from variables efi: Correct comment on efi_memmap_alloc memblock: Disable mirror feature if kernelcore is not specified ...

pstore: Add priv field to pstore_record for backend specific use

2022-06-24T18:40:04+00:00

The EFI pstore backend will need to store per-record variable name data when we switch away from the efivars layer. Add a priv field to struct pstore_record, and document it as holding a backend specific pointer that is assumed to be a kmalloc()d buffer, and will be kfree()d when the entire record is freed. Acked-by: Kees Cook Signed-off-by: Ard Biesheuvel

pstore/zone: cleanup "rcnt" type

2022-06-23T15:27:52+00:00

The info->read() function returns ssize_t. That means that info->read() either returns either negative error codes or a positive number representing the bytes read. The "rcnt" variable should be declared as ssize_t as well. Most places do this correctly but psz_kmsg_recover_meta() needed to be fixed. This code casts the "rcnt" to int. That is unnecessary when "rcnt" is already signed. It's also slightly wrong because if info->read() returned a very high (more than INT_MAX) number of bytes then this might treat that as an error. This bug cannot happen in real life, so it doesn't affect run time, but static checkers correctly complain that it is wrong. fs/pstore/zone.c:366 psz_kmsg_recover_data() warn: casting 'rcnt' truncates high bits Signed-off-by: Dan Carpenter Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/YrRtPSFHDVJzV6d+@kili