Linux kernel
============
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Pull jffs2 fix from Richard Weinberger:
- Fixup rtime compressor bounds checking
* tag 'ubifs-for-linus-6.13-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/ubifs:
jffs2: Fix rtime decompressor
Pull bpf fixes from Daniel Borkmann::
- Fix several issues for BPF LPM trie map which were found by syzbot
and during addition of new test cases (Hou Tao)
- Fix a missing process_iter_arg register type check in the BPF
verifier (Kumar Kartikeya Dwivedi, Tao Lyu)
- Fix several correctness gaps in the BPF verifier when interacting
with the BPF stack without CAP_PERFMON (Kumar Kartikeya Dwivedi,
Eduard Zingerman, Tao Lyu)
- Fix OOB BPF map writes when deleting elements for the case of xsk map
as well as devmap (Maciej Fijalkowski)
- Fix xsk sockets to always clear DMA mapping information when
unmapping the pool (Larysa Zaremba)
- Fix sk_mem_uncharge logic in tcp_bpf_sendmsg to only uncharge after
sent bytes have been finalized (Zijian Zhang)
- Fix BPF sockmap with vsocks which was missing a queue check in poll
and sockmap cleanup on close (Michal Luczaj)
- Fix tools infra to override makefile ARCH variable if defined but
empty, which addresses cross-building tools. (Björn Töpel)
- Fix two resolve_btfids build warnings on unresolved bpf_lsm symbols
(Thomas Weißschuh)
- Fix a NULL pointer dereference in bpftool (Amir Mohammadi)
- Fix BPF selftests to check for CONFIG_PREEMPTION instead of
CONFIG_PREEMPT (Sebastian Andrzej Siewior)
* tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf: (31 commits)
selftests/bpf: Add more test cases for LPM trie
selftests/bpf: Move test_lpm_map.c to map_tests
bpf: Use raw_spinlock_t for LPM trie
bpf: Switch to bpf mem allocator for LPM trie
bpf: Fix exact match conditions in trie_get_next_key()
bpf: Handle in-place update for full LPM trie correctly
bpf: Handle BPF_EXIST and BPF_NOEXIST for LPM trie
bpf: Remove unnecessary kfree(im_node) in lpm_trie_update_elem
bpf: Remove unnecessary check when updating LPM trie
selftests/bpf: Add test for narrow spill into 64-bit spilled scalar
selftests/bpf: Add test for reading from STACK_INVALID slots
selftests/bpf: Introduce __caps_unpriv annotation for tests
bpf: Fix narrow scalar spill onto 64-bit spilled scalar slots
bpf: Don't mark STACK_INVALID as STACK_MISC in mark_stack_slot_misc
samples/bpf: Remove unnecessary -I flags from libbpf EXTRA_CFLAGS
bpf: Zero index arg error string for dynptr and iter
selftests/bpf: Add tests for iter arg check
bpf: Ensure reg is PTR_TO_STACK in process_iter_arg
tools: Override makefile ARCH variable if defined, but empty
selftests/bpf: Add apply_bytes test to test_txmsg_redir_wait_sndmem in test_sockmap
...
The fix for a memory corruption contained a off-by-one error and
caused the compressor to fail in legit cases.
Cc: Kinsey Moore <kinsey.moore@oarcorp.com>
Cc: stable@vger.kernel.org
Fixes: fe051552f5078 ("jffs2: Prevent rtime decompress memory corruption")
Signed-off-by: Richard Weinberger <richard@nod.at>
Pull arm64 fixes from Catalin Marinas:
"Nothing major, some left-overs from the recent merging window (MTE,
coco) and some newly found issues like the ptrace() ones.
- MTE/hugetlbfs:
- Set VM_MTE_ALLOWED in the arch code and remove it from the core
code for hugetlbfs mappings
- Fix copy_highpage() warning when the source is a huge page but
not MTE tagged, taking the wrong small page path
- drivers/virt/coco:
- Add the pKVM and Arm CCA drivers under the arm64 maintainership
- Fix the pkvm driver to fall back to ioremap() (and warn) if the
MMIO_GUARD hypercall fails
- Keep the Arm CCA driver default 'n' rather than 'm'
- A series of fixes for the arm64 ptrace() implementation,
potentially leading to the kernel consuming uninitialised stack
variables when PTRACE_SETREGSET is invoked with a length of 0
- Fix zone_dma_limit calculation when RAM starts below 4GB and
ZONE_DMA is capped to this limit
- Fix early boot warning with CONFIG_DEBUG_VIRTUAL=y triggered by a
call to page_to_phys() (from patch_map()) which checks pfn_valid()
before vmemmap has been set up
- Do not clobber bits 15:8 of the ASID used for TTBR1_EL1 and TLBI
ops when the kernel assumes 8-bit ASIDs but running under a
hypervisor on a system that implements 16-bit ASIDs (found running
Linux under Parallels on Apple M4)
- ACPI/IORT: Add PMCG platform information for HiSilicon HIP09A as it
is using the same SMMU PMCG as HIP09 and suffers from the same
errata
- Add GCS to cpucap_is_possible(), missed in the recent merge"
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: ptrace: fix partial SETREGSET for NT_ARM_GCS
arm64: ptrace: fix partial SETREGSET for NT_ARM_POE
arm64: ptrace: fix partial SETREGSET for NT_ARM_FPMR
arm64: ptrace: fix partial SETREGSET for NT_ARM_TAGGED_ADDR_CTRL
arm64: cpufeature: Add GCS to cpucap_is_possible()
coco: virt: arm64: Do not enable cca guest driver by default
arm64: mte: Fix copy_highpage() warning on hugetlb folios
arm64: Ensure bits ASID[15:8] are masked out when the kernel uses 8-bit ASIDs
ACPI/IORT: Add PMCG platform information for HiSilicon HIP09A
MAINTAINERS: Add CCA and pKVM CoCO guest support to the ARM64 entry
drivers/virt: pkvm: Don't fail ioremap() call if MMIO_GUARD fails
arm64: patching: avoid early page_to_phys()
arm64: mm: Fix zone_dma_limit calculation
arm64: mte: set VM_MTE_ALLOWED for hugetlbfs at correct place
Hou Tao says:
====================
This patch set fixes several issues for LPM trie. These issues were
found during adding new test cases or were reported by syzbot.
The patch set is structured as follows:
Patch #1~#2 are clean-ups for lpm_trie_update_elem().
Patch #3 handles BPF_EXIST and BPF_NOEXIST correctly for LPM trie.
Patch #4 fixes the accounting of n_entries when doing in-place update.
Patch #5 fixes the exact match condition in trie_get_next_key() and it
may skip keys when the passed key is not found in the map.
Patch #6~#7 switch from kmalloc() to bpf memory allocator for LPM trie
to fix several lock order warnings reported by syzbot. It also enables
raw_spinlock_t for LPM trie again. After these changes, the LPM trie will
be closer to being usable in any context (though the reentrance check of
trie->lock is still missing, but it is on my todo list).
Patch #8: move test_lpm_map to map_tests to make it run regularly.
Patch #9: add test cases for the issues fixed by patch #3~#5.
Please see individual patches for more details. Comments are always
welcome.
Change Log:
v3:
* patch #2: remove the unnecessary NULL-init for im_node
* patch #6: alloc the leaf node before disabling IRQ to low
the possibility of -ENOMEM when leaf_size is large; Free
these nodes outside the trie lock (Suggested by Alexei)
* collect review and ack tags (Thanks for Toke & Daniel)
v2: https://lore.kernel.org/bpf/20241127004641.1118269-1-houtao@huaweicloud.com/
* collect review tags (Thanks for Toke)
* drop "Add bpf_mem_cache_is_mergeable() helper" patch
* patch #3~#4: add fix tag
* patch #4: rename the helper to trie_check_add_elem() and increase
n_entries in it.
* patch #6: use one bpf mem allocator and update commit message to
clarify that using bpf mem allocator is more appropriate.
* patch #7: update commit message to add the possible max running time
for update operation.
* patch #9: update commit message to specify the purpose of these test
cases.
v1: https://lore.kernel.org/bpf/20241118010808.2243555-1-houtao@huaweicloud.com/
====================
Link: https://lore.kernel.org/all/20241206110622.1161752-1-houtao@huaweicloud.com/
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Pull btrfs fixes from David Sterba:
- add lockdep annotations for io_uring/encoded read integration, inode
lock is held when returning to userspace
- properly reflect experimental config option to sysfs
- handle NULL root in case the rescue mode accepts invalid/damaged tree
roots (rescue=ibadroot)
- regression fix of a deadlock between transaction and extent locks
- fix pending bio accounting bug in encoded read ioctl
- fix NOWAIT mode when checking references for NOCOW files
- fix use-after-free in a rb-tree cleanup in ref-verify debugging tool
* tag 'for-6.13-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: fix lockdep warnings on io_uring encoded reads
btrfs: ref-verify: fix use-after-free after invalid ref action
btrfs: add a sanity check for btrfs root in btrfs_search_slot()
btrfs: don't loop for nowait writes when checking for cross references
btrfs: sysfs: advertise experimental features only if CONFIG_BTRFS_EXPERIMENTAL=y
btrfs: fix deadlock between transaction commits and extent locks
btrfs: fix use-after-free in btrfs_encoded_read_endio()
Pull memblock fixes from Mike Rapoport:
"Restore check for node validity in arch_numa.
The rework of NUMA initialization in arch_numa dropped a check that
refused to accept configurations with invalid node IDs.
Restore that check to ensure that when firmware passes invalid nodes,
such configuration is rejected and kernel gracefully falls back to
dummy NUMA"
* tag 'fixes-2024-12-06' of git://git.kernel.org/pub/scm/linux/kernel/git/rppt/memblock:
arch_numa: Restore nid checks before registering a memblock with a node
memblock: allow zero threshold in validate_numa_converage()
Currently gcs_set() doesn't initialize the temporary 'user_gcs'
variable, and a SETREGSET call with a length of 0, 8, or 16 will leave
some portion of this uninitialized. Consequently some arbitrary
uninitialized values may be written back to the relevant fields in task
struct, potentially leaking up to 192 bits of memory from the kernel
stack. The read is limited to a specific slot on the stack, and the
issue does not provide a write mechanism.
As gcs_set() rejects cases where user_gcs::features_enabled has bits set
other than PR_SHADOW_STACK_SUPPORTED_STATUS_MASK, a SETREGSET call with
a length of zero will randomly succeed or fail depending on the value of
the uninitialized value, it isn't possible to leak the full 192 bits.
With a length of 8 or 16, user_gcs::features_enabled can be initialized
to an accepted value, making it practical to leak 128 or 64 bits.
Fix this by initializing the temporary value before copying the regset
from userspace, as for other regsets (e.g. NT_PRSTATUS, NT_PRFPREG,
NT_ARM_SYSTEM_CALL). In the case of a zero-length or partial write, the
existing contents of the fields which are not written to will be
retained.
To ensure that the extraction and insertion of fields is consistent
across the GETREGSET and SETREGSET calls, new task_gcs_to_user() and
task_gcs_from_user() helpers are added, matching the style of
pac_address_keys_to_user() and pac_address_keys_from_user().
Before this patch:
| # ./gcs-test
| Attempting to write NT_ARM_GCS::user_gcs = {
| .features_enabled = 0x0000000000000000,
| .features_locked = 0x0000000000000000,
| .gcspr_el0 = 0x900d900d900d900d,
| }
| SETREGSET(nt=0x410, len=24) wrote 24 bytes
|
| Attempting to read NT_ARM_GCS::user_gcs
| GETREGSET(nt=0x410, len=24) read 24 bytes
| Read NT_ARM_GCS::user_gcs = {
| .features_enabled = 0x0000000000000000,
| .features_locked = 0x0000000000000000,
| .gcspr_el0 = 0x900d900d900d900d,
| }
|
| Attempting partial write NT_ARM_GCS::user_gcs = {
| .features_enabled = 0x0000000000000000,
| .features_locked = 0x1de7ec7edbadc0de,
| .gcspr_el0 = 0x1de7ec7edbadc0de,
| }
| SETREGSET(nt=0x410, len=8) wrote 8 bytes
|
| Attempting to read NT_ARM_GCS::user_gcs
| GETREGSET(nt=0x410, len=24) read 24 bytes
| Read NT_ARM_GCS::user_gcs = {
| .features_enabled = 0x0000000000000000,
| .features_locked = 0x000000000093e780,
| .gcspr_el0 = 0xffff800083a63d50,
| }
After this patch:
| # ./gcs-test
| Attempting to write NT_ARM_GCS::user_gcs = {
| .features_enabled = 0x0000000000000000,
| .features_locked = 0x0000000000000000,
| .gcspr_el0 = 0x900d900d900d900d,
| }
| SETREGSET(nt=0x410, len=24) wrote 24 bytes
|
| Attempting to read NT_ARM_GCS::user_gcs
| GETREGSET(nt=0x410, len=24) read 24 bytes
| Read NT_ARM_GCS::user_gcs = {
| .features_enabled = 0x0000000000000000,
| .features_locked = 0x0000000000000000,
| .gcspr_el0 = 0x900d900d900d900d,
| }
|
| Attempting partial write NT_ARM_GCS::user_gcs = {
| .features_enabled = 0x0000000000000000,
| .features_locked = 0x1de7ec7edbadc0de,
| .gcspr_el0 = 0x1de7ec7edbadc0de,
| }
| SETREGSET(nt=0x410, len=8) wrote 8 bytes
|
| Attempting to read NT_ARM_GCS::user_gcs
| GETREGSET(nt=0x410, len=24) read 24 bytes
| Read NT_ARM_GCS::user_gcs = {
| .features_enabled = 0x0000000000000000,
| .features_locked = 0x0000000000000000,
| .gcspr_el0 = 0x900d900d900d900d,
| }
Fixes: 7ec3b57cb29f ("arm64/ptrace: Expose GCS via ptrace and core files")
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Will Deacon <will@kernel.org>
Reviewed-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20241205121655.1824269-5-mark.rutland@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Kumar Kartikeya Dwivedi says:
====================
Fixes for stack with allow_ptr_leaks
Two fixes for usability/correctness gaps when interacting with the stack
without CAP_PERFMON (i.e. with allow_ptr_leaks = false). See the commits
for details. I've verified that the tests fail when run without the fixes.
Changelog:
----------
v3 -> v4
v3: https://lore.kernel.org/bpf/20241202083814.1888784-1-memxor@gmail.com
* Address Andrii's comments
* Fix bug paperered over by missing CAP_NET_ADMIN in verifier_mtu
test
* Add warning when undefined CAP_ constant is specified, and fail
test
* Reorder annotations to be more clear
* Verify that fixes fail without patches again
* Add Acked-by from Andrii
v2 -> v3
v2: https://lore.kernel.org/bpf/20241127212026.3580542-1-memxor@gmail.com
* Address comments from Eduard
* Fix comment for mark_stack_slot_misc
* We can simply always return early when stype == STACK_INVALID
* Drop allow_ptr_leaks conditionals
* Add Eduard's __caps_unpriv patch into the series
* Convert test_verifier_mtu to use it
* Move existing tests to __caps_unpriv annotation and verifier_spill_fill.c
* Add Acked-by from Eduard
v1 -> v2
v1: https://lore.kernel.org/bpf/20241127185135.2753982-1-memxor@gmail.com
* Fix CI errors in selftest by removing dependence on BPF_ST
====================
Link: https://patch.msgid.link/20241204044757.1483141-1-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add more test cases for LPM trie in test_maps:
1) test_lpm_trie_update_flags
It constructs various use cases for BPF_EXIST and BPF_NOEXIST and check
whether the return value of update operation is expected.
2) test_lpm_trie_update_full_maps
It tests the update operations on a full LPM trie map. Adding new node
will fail and overwriting the value of existed node will succeed.
3) test_lpm_trie_iterate_strs and test_lpm_trie_iterate_ints
There two test cases test whether the iteration through get_next_key is
sorted and expected. These two test cases delete the minimal key after
each iteration and check whether next iteration returns the second
minimal key. The only difference between these two test cases is the
former one saves strings in the LPM trie and the latter saves integers.
Without the fix of get_next_key, these two cases will fail as shown
below:
test_lpm_trie_iterate_strs(1091):FAIL:iterate #2 got abc exp abS
test_lpm_trie_iterate_ints(1142):FAIL:iterate #1 got 0x2 exp 0x1
Signed-off-by: Hou Tao <houtao1@huawei.com>
Link: https://lore.kernel.org/r/20241206110622.1161752-10-houtao@huaweicloud.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Pull quota and udf fixes from Jan Kara:
"Two small UDF fixes for better handling of corrupted filesystem and a
quota fix to fix handling of filesystem freezing"
* tag 'fs_for_v6.13-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
udf: Verify inode link counts before performing rename
udf: Skip parent dir link count update if corrupted
quota: flush quota_release_work upon quota writeback
Lockdep doesn't like the fact that btrfs_uring_read_extent() returns to
userspace still holding the inode lock, even though we release it once
the I/O finishes. Add calls to rwsem_release() and rwsem_acquire_read() to
work round this.
Reported-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
34310c442e17 ("btrfs: add io_uring command for encoded reads (ENCODED_READ ioctl)")
Signed-off-by: Mark Harmstone <maharmstone@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Pull more drm fixes from Simona Vetter:
"Due to mailing list unreliability we missed the amdgpu pull, hence
part two with that now included:
- amdgu: mostly display fixes + jpeg vcn 1.0, sriov, dcn4.0 resume
fixes
- amdkfd fixes"
* tag 'drm-fixes-2024-12-06' of https://gitlab.freedesktop.org/drm/kernel:
drm/amdgpu: rework resume handling for display (v2)
drm/amd/pm: fix and simplify workload handling
Revert "drm/amd/pm: correct the workload setting"
drm/amdgpu: fix sriov reinit late orders
drm/amdgpu: Fix ISP hw init issue
drm/amd/display: Add hblank borrowing support
drm/amd/display: Limit VTotal range to max hw cap minus fp
drm/amd/display: Correct prefetch calculation
drm/amd/display: Add option to retrieve detile buffer size
drm/amd/display: Add a left edge pixel if in YCbCr422 or YCbCr420 and odm
drm/amdkfd: hard-code cacheline for gc943,gc944
drm/amdkfd: add MEC version that supports no PCIe atomics for GFX12
drm/amd/display: Fix programming backlight on OLED panels
drm/amd: Sanity check the ACPI EDID
drm/amdgpu/hdp7.0: do a posting read when flushing HDP
drm/amdgpu/hdp6.0: do a posting read when flushing HDP
drm/amdgpu/hdp5.2: do a posting read when flushing HDP
drm/amdgpu/hdp5.0: do a posting read when flushing HDP
drm/amdgpu/hdp4.0: do a posting read when flushing HDP
drm/amdgpu/jpeg1.0: fix idle work handler
Commit 767507654c22 ("arch_numa: switch over to numa_memblks")
significantly cleaned up the NUMA registration code, but also
dropped a significant check that was refusing to accept to
configure a memblock with an invalid nid.
On "quality hardware" such as my ThunderX machine, this results
in a kernel that dies immediately:
[ 0.000000] Booting Linux on physical CPU 0x0000000000 [0x431f0a10]
[ 0.000000] Linux version 6.12.0-00013-g8920d74cf8db (maz@valley-girl) (gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40) #3872 SMP PREEMPT Wed Nov 27 15:25:49 GMT 2024
[ 0.000000] KASLR disabled due to lack of seed
[ 0.000000] Machine model: Cavium ThunderX CN88XX board
[ 0.000000] efi: EFI v2.4 by American Megatrends
[ 0.000000] efi: ESRT=0xffce0ff18 SMBIOS 3.0=0xfffb0000 ACPI 2.0=0xffec60000 MEMRESERVE=0xffc905d98
[ 0.000000] esrt: Reserving ESRT space from 0x0000000ffce0ff18 to 0x0000000ffce0ff50.
[ 0.000000] earlycon: pl11 at MMIO 0x000087e024000000 (options '115200n8')
[ 0.000000] printk: legacy bootconsole [pl11] enabled
[ 0.000000] NODE_DATA(0) allocated [mem 0xff6754580-0xff67566bf]
[ 0.000000] Unable to handle kernel paging request at virtual address 0000000000001d40
[ 0.000000] Mem abort info:
[ 0.000000] ESR = 0x0000000096000004
[ 0.000000] EC = 0x25: DABT (current EL), IL = 32 bits
[ 0.000000] SET = 0, FnV = 0
[ 0.000000] EA = 0, S1PTW = 0
[ 0.000000] FSC = 0x04: level 0 translation fault
[ 0.000000] Data abort info:
[ 0.000000] ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000
[ 0.000000] CM = 0, WnR = 0, TnD = 0, TagAccess = 0
[ 0.000000] GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
[ 0.000000] [0000000000001d40] user address but active_mm is swapper
[ 0.000000] Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP
[ 0.000000] Modules linked in:
[ 0.000000] CPU: 0 UID: 0 PID: 0 Comm: swapper Not tainted 6.12.0-00013-g8920d74cf8db #3872
[ 0.000000] Hardware name: Cavium ThunderX CN88XX board (DT)
[ 0.000000] pstate: a00000c5 (NzCv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[ 0.000000] pc : sparse_init_nid+0x54/0x428
[ 0.000000] lr : sparse_init+0x118/0x240
[ 0.000000] sp : ffff800081da3cb0
[ 0.000000] x29: ffff800081da3cb0 x28: 0000000fedbab10c x27: 0000000000000001
[ 0.000000] x26: 0000000ffee250f8 x25: 0000000000000001 x24: ffff800082102cd0
[ 0.000000] x23: 0000000000000001 x22: 0000000000000000 x21: 00000000001fffff
[ 0.000000] x20: 0000000000000001 x19: 0000000000000000 x18: ffffffffffffffff
[ 0.000000] x17: 0000000001b00000 x16: 0000000ffd130000 x15: 0000000000000000
[ 0.000000] x14: 00000000003e0000 x13: 00000000000001c8 x12: 0000000000000014
[ 0.000000] x11: ffff800081e82860 x10: ffff8000820fb2c8 x9 : ffff8000820fb490
[ 0.000000] x8 : 0000000000ffed20 x7 : 0000000000000014 x6 : 00000000001fffff
[ 0.000000] x5 : 00000000ffffffff x4 : 0000000000000000 x3 : 0000000000000000
[ 0.000000] x2 : 0000000000000000 x1 : 0000000000000040 x0 : 0000000000000007
[ 0.000000] Call trace:
[ 0.000000] sparse_init_nid+0x54/0x428
[ 0.000000] sparse_init+0x118/0x240
[ 0.000000] bootmem_init+0x70/0x1c8
[ 0.000000] setup_arch+0x184/0x270
[ 0.000000] start_kernel+0x74/0x670
[ 0.000000] __primary_switched+0x80/0x90
[ 0.000000] Code: f865d804 d37df060 cb030000 d2800003 (b95d4084)
[ 0.000000] ---[ end trace 0000000000000000 ]---
[ 0.000000] Kernel panic - not syncing: Attempted to kill the idle task!
[ 0.000000] ---[ end Kernel panic - not syncing: Attempted to kill the idle task! ]---
while previous kernel versions were able to recognise how brain-damaged
the machine is, and only build a fake node.
Use the memblock_validate_numa_coverage() helper to restore some sanity
and a "working" system.
Fixes: 767507654c22 ("arch_numa: switch over to numa_memblks")
Suggested-by: Mike Rapoport <rppt@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20241201092702.3792845-1-maz@kernel.org
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Currently poe_set() doesn't initialize the temporary 'ctrl' variable,
and a SETREGSET call with a length of zero will leave this
uninitialized. Consequently an arbitrary value will be written back to
target->thread.por_el0, potentially leaking up to 64 bits of memory from
the kernel stack. The read is limited to a specific slot on the stack,
and the issue does not provide a write mechanism.
Fix this by initializing the temporary value before copying the regset
from userspace, as for other regsets (e.g. NT_PRSTATUS, NT_PRFPREG,
NT_ARM_SYSTEM_CALL). In the case of a zero-length write, the existing
contents of POR_EL1 will be retained.
Before this patch:
| # ./poe-test
| Attempting to write NT_ARM_POE::por_el0 = 0x900d900d900d900d
| SETREGSET(nt=0x40f, len=8) wrote 8 bytes
|
| Attempting to read NT_ARM_POE::por_el0
| GETREGSET(nt=0x40f, len=8) read 8 bytes
| Read NT_ARM_POE::por_el0 = 0x900d900d900d900d
|
| Attempting to write NT_ARM_POE (zero length)
| SETREGSET(nt=0x40f, len=0) wrote 0 bytes
|
| Attempting to read NT_ARM_POE::por_el0
| GETREGSET(nt=0x40f, len=8) read 8 bytes
| Read NT_ARM_POE::por_el0 = 0xffff8000839c3d50
After this patch:
| # ./poe-test
| Attempting to write NT_ARM_POE::por_el0 = 0x900d900d900d900d
| SETREGSET(nt=0x40f, len=8) wrote 8 bytes
|
| Attempting to read NT_ARM_POE::por_el0
| GETREGSET(nt=0x40f, len=8) read 8 bytes
| Read NT_ARM_POE::por_el0 = 0x900d900d900d900d
|
| Attempting to write NT_ARM_POE (zero length)
| SETREGSET(nt=0x40f, len=0) wrote 0 bytes
|
| Attempting to read NT_ARM_POE::por_el0
| GETREGSET(nt=0x40f, len=8) read 8 bytes
| Read NT_ARM_POE::por_el0 = 0x900d900d900d900d
Fixes: 175198199262 ("arm64/ptrace: add support for FEAT_POE")
Cc: <stable@vger.kernel.org> # 6.12.x
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Joey Gouly <joey.gouly@arm.com>
Cc: Will Deacon <will@kernel.org>
Reviewed-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20241205121655.1824269-4-mark.rutland@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Commit [0] breaks samples/bpf build:
$ make M=samples/bpf
...
make -C /path/to/kernel/samples/bpf/../../tools/lib/bpf \
...
EXTRA_CFLAGS=" \
...
-fsanitize=bounds \
-I/path/to/kernel/usr/include \
...
/path/to/kernel/samples/bpf/libbpf/libbpf.a install_headers
CC /path/to/kernel/samples/bpf/libbpf/staticobjs/libbpf.o
In file included from libbpf.c:29:
/path/to/kernel/tools/include/linux/err.h:35:8: error: 'inline' can only appear on functions
35 | static inline void * __must_check ERR_PTR(long error_)
| ^
The error is caused by `objtree` variable changing definition from `.`
(dot) to an absolute path:
- The variable TPROGS_CFLAGS is constructed as follows:
...
TPROGS_CFLAGS += -I$(objtree)/usr/include
- It is passed as EXTRA_CFLAGS for libbpf compilation:
$(LIBBPF): ...
...
$(MAKE) -C $(LIBBPF_SRC) RM='rm -rf' EXTRA_CFLAGS="$(TPROGS_CFLAGS)"
- Before commit [0], the line passed to libbpf makefile was
'-I./usr/include', where '.' referred to LIBBPF_SRC due to -C flag.
The directory $(LIBBPF_SRC)/usr/include does not exist and thus
was never resolved by C compiler.
- After commit [0], the line passed to libbpf makefile became:
'<output-dir>/usr/include', this directory exists and is resolved by
C compiler.
- Both 'tools/include' and 'usr/include' define files err.h and types.h.
- libbpf expects headers like 'linux/err.h' and 'linux/types.h'
defined in 'tools/include', not 'usr/include', hence the compilation
error.
This commit removes unnecessary -I flags from libbpf compilation.
(libbpf sets up the necessary includes at lib/bpf/Makefile:63).
Changes v1 [1] -> v2:
- dropped unnecessary replacement of KBUILD_OUTPUT with $(objtree)
(Andrii)
Changes v2 [2] -> v3:
- make sure --sysroot option is set for libbpf's EXTRA_CFLAGS,
if $(SYSROOT) is set (Stanislav)
[0] commit 13b25489b6f8 ("kbuild: change working directory to external module directory with M=")
[1] https://lore.kernel.org/bpf/20241202212154.3174402-1-eddyz87@gmail.com/
[2] https://lore.kernel.org/bpf/20241202234741.3492084-1-eddyz87@gmail.com/
Fixes: 13b25489b6f8 ("kbuild: change working directory to external module directory with M=")
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://lore.kernel.org/bpf/20241203182222.3915763-1-eddyz87@gmail.com