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Linux kernel
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Pull x86 fixes from Borislav Petkov:
- Make sure a kdump kernel with CONFIG_IMA_KEXEC enabled and booted on
an AMD SME enabled hardware properly decrypts the ima_kexec buffer
information passed to it from the previous kernel
- Fix building the kernel with Clang where a non-TLS definition of the
stack protector guard cookie leads to bogus code generation
- Clear a wrongly advertised virtualized VMLOAD/VMSAVE feature flag on
some Zen4 client systems as those insns are not supported on client
* tag 'x86_urgent_for_v6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mm: Fix a kdump kernel failure on SME system when CONFIG_IMA_KEXEC=y
x86/stackprotector: Work around strict Clang TLS symbol requirements
x86/CPU/AMD: Clear virtualized VMLOAD/VMSAVE on Zen4 client
Pull hotfixes from Andrew Morton:
"10 hotfixes, 7 of which are cc:stable. All singletons, please see the
changelogs for details"
* tag 'mm-hotfixes-stable-2024-11-16-15-33' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
mm: revert "mm: shmem: fix data-race in shmem_getattr()"
ocfs2: uncache inode which has failed entering the group
mm: fix NULL pointer dereference in alloc_pages_bulk_noprof
mm, doc: update read_ahead_kb for MADV_HUGEPAGE
fs/proc/task_mmu: prevent integer overflow in pagemap_scan_get_args()
sched/task_stack: fix object_is_on_stack() for KASAN tagged pointers
crash, powerpc: default to CRASH_DUMP=n on PPC_BOOK3S_32
mm/mremap: fix address wraparound in move_page_tables()
tools/mm: fix compile error
mm, swap: fix allocation and scanning race with swapoff
The kdump kernel is broken on SME systems with CONFIG_IMA_KEXEC=y enabled.
Debugging traced the issue back to
b69a2afd5afc ("x86/kexec: Carry forward IMA measurement log on kexec").
Testing was previously not conducted on SME systems with CONFIG_IMA_KEXEC
enabled, which led to the oversight, with the following incarnation:
...
ima: No TPM chip found, activating TPM-bypass!
Loading compiled-in module X.509 certificates
Loaded X.509 cert 'Build time autogenerated kernel key: 18ae0bc7e79b64700122bb1d6a904b070fef2656'
ima: Allocated hash algorithm: sha256
Oops: general protection fault, probably for non-canonical address 0xcfacfdfe6660003e: 0000 [#1] PREEMPT SMP NOPTI
CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.11.0-rc2+ #14
Hardware name: Dell Inc. PowerEdge R7425/02MJ3T, BIOS 1.20.0 05/03/2023
RIP: 0010:ima_restore_measurement_list
Call Trace:
<TASK>
? show_trace_log_lvl
? show_trace_log_lvl
? ima_load_kexec_buffer
? __die_body.cold
? die_addr
? exc_general_protection
? asm_exc_general_protection
? ima_restore_measurement_list
? vprintk_emit
? ima_load_kexec_buffer
ima_load_kexec_buffer
ima_init
? __pfx_init_ima
init_ima
? __pfx_init_ima
do_one_initcall
do_initcalls
? __pfx_kernel_init
kernel_init_freeable
kernel_init
ret_from_fork
? __pfx_kernel_init
ret_from_fork_asm
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
...
Kernel panic - not syncing: Fatal exception
Kernel Offset: disabled
Rebooting in 10 seconds..
Adding debug printks showed that the stored addr and size of ima_kexec buffer
are not decrypted correctly like:
ima: ima_load_kexec_buffer, buffer:0xcfacfdfe6660003e, size:0xe48066052d5df359
Three types of setup_data info
— SETUP_EFI,
- SETUP_IMA, and
- SETUP_RNG_SEED
are passed to the kexec/kdump kernel. Only the ima_kexec buffer
experienced incorrect decryption. Debugging identified a bug in
early_memremap_is_setup_data(), where an incorrect range calculation
occurred due to the len variable in struct setup_data ended up only
representing the length of the data field, excluding the struct's size,
and thus leading to miscalculation.
Address a similar issue in memremap_is_setup_data() while at it.
[ bp: Heavily massage. ]
Fixes: b3c72fc9a78e ("x86/boot: Introduce setup_indirect")
Signed-off-by: Baoquan He <bhe@redhat.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Acked-by: Tom Lendacky <thomas.lendacky@amd.com>
Cc: <stable@kernel.org>
Link: https://lore.kernel.org/r/20240911081615.262202-3-bhe@redhat.com
Pull ARM fixes from Russell King:
- Fix kernel mapping for XIP kernels
- Fix SMP support for XIP kernels
- Fix complication corner case with CFI
- Fix a typo in nommu code
- Fix cacheflush syscall when PAN is enabled on LPAE platforms
* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rmk/linux:
ARM: fix cacheflush with PAN
ARM: 9435/1: ARM/nommu: Fix typo "absence"
ARM: 9434/1: cfi: Fix compilation corner case
ARM: 9420/1: smp: Fix SMP for xip kernels
ARM: 9419/1: mm: Fix kernel memory mapping for xip kernels
Revert d949d1d14fa2 ("mm: shmem: fix data-race in shmem_getattr()") as
suggested by Chuck [1]. It is causing deadlocks when accessing tmpfs over
NFS.
As Hugh commented, "added just to silence a syzbot sanitizer splat: added
where there has never been any practical problem".
Link: https://lkml.kernel.org/r/ZzdxKF39VEmXSSyN@tissot.1015granger.net [1]
Fixes: d949d1d14fa2 ("mm: shmem: fix data-race in shmem_getattr()")
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: Jeongjun Park <aha310510@gmail.com>
Cc: Yu Zhao <yuzhao@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
GCC and Clang both implement stack protector support based on Thread Local
Storage (TLS) variables, and this is used in the kernel to implement per-task
stack cookies, by copying a task's stack cookie into a per-CPU variable every
time it is scheduled in.
Both now also implement -mstack-protector-guard-symbol=, which permits the TLS
variable to be specified directly. This is useful because it will allow to
move away from using a fixed offset of 40 bytes into the per-CPU area on
x86_64, which requires a lot of special handling in the per-CPU code and the
runtime relocation code.
However, while GCC is rather lax in its implementation of this command line
option, Clang actually requires that the provided symbol name refers to a TLS
variable (i.e., one declared with __thread), although it also permits the
variable to be undeclared entirely, in which case it will use an implicit
declaration of the right type.
The upshot of this is that Clang will emit the correct references to the stack
cookie variable in most cases, e.g.,
10d: 64 a1 00 00 00 00 mov %fs:0x0,%eax
10f: R_386_32 __stack_chk_guard
However, if a non-TLS definition of the symbol in question is visible in the
same compilation unit (which amounts to the whole of vmlinux if LTO is
enabled), it will drop the per-CPU prefix and emit a load from a bogus
address.
Work around this by using a symbol name that never occurs in C code, and emit
it as an alias in the linker script.
Fixes: 3fb0fdb3bbe7 ("x86/stackprotector/32: Make the canary into a regular percpu variable")
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Brian Gerst <brgerst@gmail.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Cc: stable@vger.kernel.org
Link: https://github.com/ClangBuiltLinux/linux/issues/1854
Link: https://lore.kernel.org/r/20241105155801.1779119-2-brgerst@gmail.com
Pull drm fix from Dave Airlie:
"Alex sent on a last minute revert for a amdgpu/swsmu regression:
- revert patch to fix swsmu regression"
* tag 'drm-fixes-2024-11-17' of https://gitlab.freedesktop.org/drm/kernel:
Revert "drm/amd/pm: correct the workload setting"
It seems that the cacheflush syscall got broken when PAN for LPAE was
implemented. User access was not enabled around the cache maintenance
instructions, causing them to fault.
Fixes: 7af5b901e847 ("ARM: 9358/2: Implement PAN for LPAE by TTBR0 page table walks disablement")
Reported-by: Michał Pecio <michal.pecio@gmail.com>
Tested-by: Michał Pecio <michal.pecio@gmail.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Syzbot has reported the following BUG:
kernel BUG at fs/ocfs2/uptodate.c:509!
...
Call Trace:
<TASK>
? __die_body+0x5f/0xb0
? die+0x9e/0xc0
? do_trap+0x15a/0x3a0
? ocfs2_set_new_buffer_uptodate+0x145/0x160
? do_error_trap+0x1dc/0x2c0
? ocfs2_set_new_buffer_uptodate+0x145/0x160
? __pfx_do_error_trap+0x10/0x10
? handle_invalid_op+0x34/0x40
? ocfs2_set_new_buffer_uptodate+0x145/0x160
? exc_invalid_op+0x38/0x50
? asm_exc_invalid_op+0x1a/0x20
? ocfs2_set_new_buffer_uptodate+0x2e/0x160
? ocfs2_set_new_buffer_uptodate+0x144/0x160
? ocfs2_set_new_buffer_uptodate+0x145/0x160
ocfs2_group_add+0x39f/0x15a0
? __pfx_ocfs2_group_add+0x10/0x10
? __pfx_lock_acquire+0x10/0x10
? mnt_get_write_access+0x68/0x2b0
? __pfx_lock_release+0x10/0x10
? rcu_read_lock_any_held+0xb7/0x160
? __pfx_rcu_read_lock_any_held+0x10/0x10
? smack_log+0x123/0x540
? mnt_get_write_access+0x68/0x2b0
? mnt_get_write_access+0x68/0x2b0
? mnt_get_write_access+0x226/0x2b0
ocfs2_ioctl+0x65e/0x7d0
? __pfx_ocfs2_ioctl+0x10/0x10
? smack_file_ioctl+0x29e/0x3a0
? __pfx_smack_file_ioctl+0x10/0x10
? lockdep_hardirqs_on_prepare+0x43d/0x780
? __pfx_lockdep_hardirqs_on_prepare+0x10/0x10
? __pfx_ocfs2_ioctl+0x10/0x10
__se_sys_ioctl+0xfb/0x170
do_syscall_64+0xf3/0x230
entry_SYSCALL_64_after_hwframe+0x77/0x7f
...
</TASK>
When 'ioctl(OCFS2_IOC_GROUP_ADD, ...)' has failed for the particular
inode in 'ocfs2_verify_group_and_input()', corresponding buffer head
remains cached and subsequent call to the same 'ioctl()' for the same
inode issues the BUG() in 'ocfs2_set_new_buffer_uptodate()' (trying
to cache the same buffer head of that inode). Fix this by uncaching
the buffer head with 'ocfs2_remove_from_cache()' on error path in
'ocfs2_group_add()'.
Link: https://lkml.kernel.org/r/20241114043844.111847-1-dmantipov@yandex.ru
Fixes: 7909f2bf8353 ("[PATCH 2/2] ocfs2: Implement group add for online resize")
Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru>
Reported-by: syzbot+453873f1588c2d75b447@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=453873f1588c2d75b447
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Dmitry Antipov <dmantipov@yandex.ru>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Jun Piao <piaojun@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
A number of Zen4 client SoCs advertise the ability to use virtualized
VMLOAD/VMSAVE, but using these instructions is reported to be a cause
of a random host reboot.
These instructions aren't intended to be advertised on Zen4 client
so clear the capability.
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Cc: stable@vger.kernel.org
Link: https://bugzilla.kernel.org/show_bug.cgi?id=219009
Pull ring buffer fixes from Steven Rostedt:
- Revert: "ring-buffer: Do not have boot mapped buffers hook to CPU
hotplug"
A crash that happened on cpu hotplug was actually caused by the
incorrect ref counting that was fixed by commit 2cf9733891a4
("ring-buffer: Fix refcount setting of boot mapped buffers"). The
removal of calling cpu hotplug callbacks on memory mapped buffers was
not an issue even though the tests at the time pointed toward it. But
in fact, there's a check in that code that tests to see if the
buffers are already allocated or not, and will not allocate them
again if they are. Not calling the cpu hotplug callbacks ended up not
initializing the non boot CPU buffers.
Simply remove that change.
- Clear all CPU buffers when starting tracing in a boot mapped buffer
To properly process events from a previous boot, the address space
needs to be accounted for due to KASLR and the events in the buffer
are updated accordingly when read. This also requires that when the
buffer has tracing enabled again in the current boot that the buffers
are reset so that events from the previous boot do not interact with
the events of the current boot and cause confusing due to not having
the proper meta data.
It was found that if a CPU is taken offline, that its per CPU buffer
is not reset when tracing starts. This allows for events to be from
both the previous boot and the current boot to be in the buffer at
the same time. Clear all CPU buffers when tracing is started in a
boot mapped buffer.
* tag 'trace-ringbuffer-v6.12-rc7-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
tracing/ring-buffer: Clear all memory mapped CPU ring buffers on first recording
Revert: "ring-buffer: Do not have boot mapped buffers hook to CPU hotplug"
amd-drm-fixes-6.12-2024-11-16:
amdgpu:
- Revert a swsmu patch to fix a regression
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Alex Deucher <alexdeucher@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20241116145320.2507156-1-alexander.deucher@amd.com
There is a spelling mistake of 'absense' in comments which
should be 'absence'.
Link: https://lore.kernel.org/all/fca25741-c89f-43ea-95af-5e3232d513fc@arm.com/
Signed-off-by: WangYuli <wangyuli@uniontech.com>
Reviewed-by: Vladimir Murzin <vladimir.murzin@arm.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
We triggered a NULL pointer dereference for ac.preferred_zoneref->zone in
alloc_pages_bulk_noprof() when the task is migrated between cpusets.
When cpuset is enabled, in prepare_alloc_pages(), ac->nodemask may be
¤t->mems_allowed. when first_zones_zonelist() is called to find
preferred_zoneref, the ac->nodemask may be modified concurrently if the
task is migrated between different cpusets. Assuming we have 2 NUMA Node,
when traversing Node1 in ac->zonelist, the nodemask is 2, and when
traversing Node2 in ac->zonelist, the nodemask is 1. As a result, the
ac->preferred_zoneref points to NULL zone.
In alloc_pages_bulk_noprof(), for_each_zone_zonelist_nodemask() finds a
allowable zone and calls zonelist_node_idx(ac.preferred_zoneref), leading
to NULL pointer dereference.
__alloc_pages_noprof() fixes this issue by checking NULL pointer in commit
ea57485af8f4 ("mm, page_alloc: fix check for NULL preferred_zone") and
commit df76cee6bbeb ("mm, page_alloc: remove redundant checks from alloc
fastpath").
To fix it, check NULL pointer for preferred_zoneref->zone.
Link: https://lkml.kernel.org/r/20241113083235.166798-1-tujinjiang@huawei.com
Fixes: 387ba26fb1cb ("mm/page_alloc: add a bulk page allocator")
Signed-off-by: Jinjiang Tu <tujinjiang@huawei.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Alexander Lobakin <alobakin@pm.me>
Cc: David Hildenbrand <david@redhat.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Nanyong Sun <sunnanyong@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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