| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
blk-iocost: fix divide by 0 error in calc_lcoefs()
echo max of u64 to cost.model can cause divide by 0 error.
# echo 8:0 rbps=18446744073709551615 > /sys/fs/cgroup/io.cost.model
divide error: 0000 [#1] PREEMPT SMP
RIP: 0010:calc_lcoefs+0x4c/0xc0
Call Trace:
<TASK>
ioc_refresh_params+0x2b3/0x4f0
ioc_cost_model_write+0x3cb/0x4c0
? _copy_from_iter+0x6d/0x6c0
? kernfs_fop_write_iter+0xfc/0x270
cgroup_file_write+0xa0/0x200
kernfs_fop_write_iter+0x17d/0x270
vfs_write+0x414/0x620
ksys_write+0x73/0x160
__x64_sys_write+0x1e/0x30
do_syscall_64+0x35/0x80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
calc_lcoefs() uses the input value of cost.model in DIV_ROUND_UP_ULL,
overflow would happen if bps plus IOC_PAGE_SIZE is greater than
ULLONG_MAX, it can cause divide by 0 error.
Fix the problem by setting basecost |
| In the Linux kernel, the following vulnerability has been resolved:
md/raid0, raid10: Don't set discard sectors for request queue
It should use disk_stack_limits to get a proper max_discard_sectors
rather than setting a value by stack drivers.
And there is a bug. If all member disks are rotational devices,
raid0/raid10 set max_discard_sectors. So the member devices are
not ssd/nvme, but raid0/raid10 export the wrong value. It reports
warning messages in function __blkdev_issue_discard when mkfs.xfs
like this:
[ 4616.022599] ------------[ cut here ]------------
[ 4616.027779] WARNING: CPU: 4 PID: 99634 at block/blk-lib.c:50 __blkdev_issue_discard+0x16a/0x1a0
[ 4616.140663] RIP: 0010:__blkdev_issue_discard+0x16a/0x1a0
[ 4616.146601] Code: 24 4c 89 20 31 c0 e9 fe fe ff ff c1 e8 09 8d 48 ff 4c 89 f0 4c 09 e8 48 85 c1 0f 84 55 ff ff ff b8 ea ff ff ff e9 df fe ff ff <0f> 0b 48 8d 74 24 08 e8 ea d6 00 00 48 c7 c6 20 1e 89 ab 48 c7 c7
[ 4616.167567] RSP: 0018:ffffaab88cbffca8 EFLAGS: 00010246
[ 4616.173406] RAX: ffff9ba1f9e44678 RBX: 0000000000000000 RCX: ffff9ba1c9792080
[ 4616.181376] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff9ba1c9792080
[ 4616.189345] RBP: 0000000000000cc0 R08: ffffaab88cbffd10 R09: 0000000000000000
[ 4616.197317] R10: 0000000000000012 R11: 0000000000000000 R12: 0000000000000000
[ 4616.205288] R13: 0000000000400000 R14: 0000000000000cc0 R15: ffff9ba1c9792080
[ 4616.213259] FS: 00007f9a5534e980(0000) GS:ffff9ba1b7c80000(0000) knlGS:0000000000000000
[ 4616.222298] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 4616.228719] CR2: 000055a390a4c518 CR3: 0000000123e40006 CR4: 00000000001706e0
[ 4616.236689] Call Trace:
[ 4616.239428] blkdev_issue_discard+0x52/0xb0
[ 4616.244108] blkdev_common_ioctl+0x43c/0xa00
[ 4616.248883] blkdev_ioctl+0x116/0x280
[ 4616.252977] __x64_sys_ioctl+0x8a/0xc0
[ 4616.257163] do_syscall_64+0x5c/0x90
[ 4616.261164] ? handle_mm_fault+0xc5/0x2a0
[ 4616.265652] ? do_user_addr_fault+0x1d8/0x690
[ 4616.270527] ? do_syscall_64+0x69/0x90
[ 4616.274717] ? exc_page_fault+0x62/0x150
[ 4616.279097] entry_SYSCALL_64_after_hwframe+0x63/0xcd
[ 4616.284748] RIP: 0033:0x7f9a55398c6b |
| In the Linux kernel, the following vulnerability has been resolved:
iommufd: Don't overflow during division for dirty tracking
If pgshift is 63 then BITS_PER_TYPE(*bitmap->bitmap) * pgsize will overflow
to 0 and this triggers divide by 0.
In this case the index should just be 0, so reorganize things to divide
by shift and avoid hitting any overflows. |
| Cypress Solutions CTM-200/CTM-ONE 1.3.6 contains hard-coded credentials vulnerability in Linux distribution that exposes root access. Attackers can exploit the static 'Chameleon' password to gain remote root access via Telnet or SSH on affected devices. |
| In the Linux kernel, the following vulnerability has been resolved:
ext4: fix rbtree traversal bug in ext4_mb_use_preallocated
During allocations, while looking for preallocations(PA) in the per
inode rbtree, we can't do a direct traversal of the tree because
ext4_mb_discard_group_preallocation() can paralelly mark the pa deleted
and that can cause direct traversal to skip some entries. This was
leading to a BUG_ON() being hit [1] when we missed a PA that could satisfy
our request and ultimately tried to create a new PA that would overlap
with the missed one.
To makes sure we handle that case while still keeping the performance of
the rbtree, we make use of the fact that the only pa that could possibly
overlap the original goal start is the one that satisfies the below
conditions:
1. It must have it's logical start immediately to the left of
(ie less than) original logical start.
2. It must not be deleted
To find this pa we use the following traversal method:
1. Descend into the rbtree normally to find the immediate neighboring
PA. Here we keep descending irrespective of if the PA is deleted or if
it overlaps with our request etc. The goal is to find an immediately
adjacent PA.
2. If the found PA is on right of original goal, use rb_prev() to find
the left adjacent PA.
3. Check if this PA is deleted and keep moving left with rb_prev() until
a non deleted PA is found.
4. This is the PA we are looking for. Now we can check if it can satisfy
the original request and proceed accordingly.
This approach also takes care of having deleted PAs in the tree.
(While we are at it, also fix a possible overflow bug in calculating the
end of a PA)
[1] https://lore.kernel.org/linux-ext4/CA+G9fYv2FRpLqBZf34ZinR8bU2_ZRAUOjKAD3+tKRFaEQHtt8Q@mail.gmail.com/ |
| In the Linux kernel, the following vulnerability has been resolved:
ASoC: mediatek: common: Fix refcount leak in parse_dai_link_info
Add missing of_node_put()s before the returns to balance
of_node_get()s and of_node_put()s, which may get unbalanced
in case the for loop 'for_each_available_child_of_node' returns
early. |
| In the Linux kernel, the following vulnerability has been resolved:
f2fs: invalidate dentry cache on failed whiteout creation
F2FS can mount filesystems with corrupted directory depth values that
get runtime-clamped to MAX_DIR_HASH_DEPTH. When RENAME_WHITEOUT
operations are performed on such directories, f2fs_rename performs
directory modifications (updating target entry and deleting source
entry) before attempting to add the whiteout entry via f2fs_add_link.
If f2fs_add_link fails due to the corrupted directory structure, the
function returns an error to VFS, but the partial directory
modifications have already been committed to disk. VFS assumes the
entire rename operation failed and does not update the dentry cache,
leaving stale mappings.
In the error path, VFS does not call d_move() to update the dentry
cache. This results in new_dentry still pointing to the old inode
(new_inode) which has already had its i_nlink decremented to zero.
The stale cache causes subsequent operations to incorrectly reference
the freed inode.
This causes subsequent operations to use cached dentry information that
no longer matches the on-disk state. When a second rename targets the
same entry, VFS attempts to decrement i_nlink on the stale inode, which
may already have i_nlink=0, triggering a WARNING in drop_nlink().
Example sequence:
1. First rename (RENAME_WHITEOUT): file2 → file1
- f2fs updates file1 entry on disk (points to inode 8)
- f2fs deletes file2 entry on disk
- f2fs_add_link(whiteout) fails (corrupted directory)
- Returns error to VFS
- VFS does not call d_move() due to error
- VFS cache still has: file1 → inode 7 (stale!)
- inode 7 has i_nlink=0 (already decremented)
2. Second rename: file3 → file1
- VFS uses stale cache: file1 → inode 7
- Tries to drop_nlink on inode 7 (i_nlink already 0)
- WARNING in drop_nlink()
Fix this by explicitly invalidating old_dentry and new_dentry when
f2fs_add_link fails during whiteout creation. This forces VFS to
refresh from disk on subsequent operations, ensuring cache consistency
even when the rename partially succeeds.
Reproducer:
1. Mount F2FS image with corrupted i_current_depth
2. renameat2(file2, file1, RENAME_WHITEOUT)
3. renameat2(file3, file1, 0)
4. System triggers WARNING in drop_nlink() |
| In the Linux kernel, the following vulnerability has been resolved:
ntfs: set dummy blocksize to read boot_block when mounting
When mounting, sb->s_blocksize is used to read the boot_block without
being defined or validated. Set a dummy blocksize before attempting to
read the boot_block.
The issue can be triggered with the following syz reproducer:
mkdirat(0xffffffffffffff9c, &(0x7f0000000080)='./file1\x00', 0x0)
r4 = openat$nullb(0xffffffffffffff9c, &(0x7f0000000040), 0x121403, 0x0)
ioctl$FS_IOC_SETFLAGS(r4, 0x40081271, &(0x7f0000000980)=0x4000)
mount(&(0x7f0000000140)=@nullb, &(0x7f0000000040)='./cgroup\x00',
&(0x7f0000000000)='ntfs3\x00', 0x2208004, 0x0)
syz_clone(0x88200200, 0x0, 0x0, 0x0, 0x0, 0x0)
Here, the ioctl sets the bdev block size to 16384. During mount,
get_tree_bdev_flags() calls sb_set_blocksize(sb, block_size(bdev)),
but since block_size(bdev) > PAGE_SIZE, sb_set_blocksize() leaves
sb->s_blocksize at zero.
Later, ntfs_init_from_boot() attempts to read the boot_block while
sb->s_blocksize is still zero, which triggers the bug.
[almaz.alexandrovich@paragon-software.com: changed comment style, added
return value handling] |
| In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix to avoid potential deadlock
As Jiaming Zhang and syzbot reported, there is potential deadlock in
f2fs as below:
Chain exists of:
&sbi->cp_rwsem --> fs_reclaim --> sb_internal#2
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
rlock(sb_internal#2);
lock(fs_reclaim);
lock(sb_internal#2);
rlock(&sbi->cp_rwsem);
*** DEADLOCK ***
3 locks held by kswapd0/73:
#0: ffffffff8e247a40 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat mm/vmscan.c:7015 [inline]
#0: ffffffff8e247a40 (fs_reclaim){+.+.}-{0:0}, at: kswapd+0x951/0x2800 mm/vmscan.c:7389
#1: ffff8880118400e0 (&type->s_umount_key#50){.+.+}-{4:4}, at: super_trylock_shared fs/super.c:562 [inline]
#1: ffff8880118400e0 (&type->s_umount_key#50){.+.+}-{4:4}, at: super_cache_scan+0x91/0x4b0 fs/super.c:197
#2: ffff888011840610 (sb_internal#2){.+.+}-{0:0}, at: f2fs_evict_inode+0x8d9/0x1b60 fs/f2fs/inode.c:890
stack backtrace:
CPU: 0 UID: 0 PID: 73 Comm: kswapd0 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
<TASK>
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
print_circular_bug+0x2ee/0x310 kernel/locking/lockdep.c:2043
check_noncircular+0x134/0x160 kernel/locking/lockdep.c:2175
check_prev_add kernel/locking/lockdep.c:3165 [inline]
check_prevs_add kernel/locking/lockdep.c:3284 [inline]
validate_chain+0xb9b/0x2140 kernel/locking/lockdep.c:3908
__lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5237
lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868
down_read+0x46/0x2e0 kernel/locking/rwsem.c:1537
f2fs_down_read fs/f2fs/f2fs.h:2278 [inline]
f2fs_lock_op fs/f2fs/f2fs.h:2357 [inline]
f2fs_do_truncate_blocks+0x21c/0x10c0 fs/f2fs/file.c:791
f2fs_truncate_blocks+0x10a/0x300 fs/f2fs/file.c:867
f2fs_truncate+0x489/0x7c0 fs/f2fs/file.c:925
f2fs_evict_inode+0x9f2/0x1b60 fs/f2fs/inode.c:897
evict+0x504/0x9c0 fs/inode.c:810
f2fs_evict_inode+0x1dc/0x1b60 fs/f2fs/inode.c:853
evict+0x504/0x9c0 fs/inode.c:810
dispose_list fs/inode.c:852 [inline]
prune_icache_sb+0x21b/0x2c0 fs/inode.c:1000
super_cache_scan+0x39b/0x4b0 fs/super.c:224
do_shrink_slab+0x6ef/0x1110 mm/shrinker.c:437
shrink_slab_memcg mm/shrinker.c:550 [inline]
shrink_slab+0x7ef/0x10d0 mm/shrinker.c:628
shrink_one+0x28a/0x7c0 mm/vmscan.c:4955
shrink_many mm/vmscan.c:5016 [inline]
lru_gen_shrink_node mm/vmscan.c:5094 [inline]
shrink_node+0x315d/0x3780 mm/vmscan.c:6081
kswapd_shrink_node mm/vmscan.c:6941 [inline]
balance_pgdat mm/vmscan.c:7124 [inline]
kswapd+0x147c/0x2800 mm/vmscan.c:7389
kthread+0x70e/0x8a0 kernel/kthread.c:463
ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>
The root cause is deadlock among four locks as below:
kswapd
- fs_reclaim --- Lock A
- shrink_one
- evict
- f2fs_evict_inode
- sb_start_intwrite --- Lock B
- iput
- evict
- f2fs_evict_inode
- sb_start_intwrite --- Lock B
- f2fs_truncate
- f2fs_truncate_blocks
- f2fs_do_truncate_blocks
- f2fs_lock_op --- Lock C
ioctl
- f2fs_ioc_commit_atomic_write
- f2fs_lock_op --- Lock C
- __f2fs_commit_atomic_write
- __replace_atomic_write_block
- f2fs_get_dnode_of_data
- __get_node_folio
- f2fs_check_nid_range
- f2fs_handle_error
- f2fs_record_errors
- f2fs_down_write --- Lock D
open
- do_open
- do_truncate
- security_inode_need_killpriv
- f2fs_getxattr
- lookup_all_xattrs
- f2fs_handle_error
- f2fs_record_errors
- f2fs_down_write --- Lock D
- f2fs_commit_super
- read_mapping_folio
- filemap_alloc_folio_noprof
- prepare_alloc_pages
- fs_reclaim_acquire --- Lock A
In order to a
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
fuse: fix readahead reclaim deadlock
Commit e26ee4efbc79 ("fuse: allocate ff->release_args only if release is
needed") skips allocating ff->release_args if the server does not
implement open. However in doing so, fuse_prepare_release() now skips
grabbing the reference on the inode, which makes it possible for an
inode to be evicted from the dcache while there are inflight readahead
requests. This causes a deadlock if the server triggers reclaim while
servicing the readahead request and reclaim attempts to evict the inode
of the file being read ahead. Since the folio is locked during
readahead, when reclaim evicts the fuse inode and fuse_evict_inode()
attempts to remove all folios associated with the inode from the page
cache (truncate_inode_pages_range()), reclaim will block forever waiting
for the lock since readahead cannot relinquish the lock because it is
itself blocked in reclaim:
>>> stack_trace(1504735)
folio_wait_bit_common (mm/filemap.c:1308:4)
folio_lock (./include/linux/pagemap.h:1052:3)
truncate_inode_pages_range (mm/truncate.c:336:10)
fuse_evict_inode (fs/fuse/inode.c:161:2)
evict (fs/inode.c:704:3)
dentry_unlink_inode (fs/dcache.c:412:3)
__dentry_kill (fs/dcache.c:615:3)
shrink_kill (fs/dcache.c:1060:12)
shrink_dentry_list (fs/dcache.c:1087:3)
prune_dcache_sb (fs/dcache.c:1168:2)
super_cache_scan (fs/super.c:221:10)
do_shrink_slab (mm/shrinker.c:435:9)
shrink_slab (mm/shrinker.c:626:10)
shrink_node (mm/vmscan.c:5951:2)
shrink_zones (mm/vmscan.c:6195:3)
do_try_to_free_pages (mm/vmscan.c:6257:3)
do_swap_page (mm/memory.c:4136:11)
handle_pte_fault (mm/memory.c:5562:10)
handle_mm_fault (mm/memory.c:5870:9)
do_user_addr_fault (arch/x86/mm/fault.c:1338:10)
handle_page_fault (arch/x86/mm/fault.c:1481:3)
exc_page_fault (arch/x86/mm/fault.c:1539:2)
asm_exc_page_fault+0x22/0x27
Fix this deadlock by allocating ff->release_args and grabbing the
reference on the inode when preparing the file for release even if the
server does not implement open. The inode reference will be dropped when
the last reference on the fuse file is dropped (see fuse_file_put() ->
fuse_release_end()). |
| In the Linux kernel, the following vulnerability has been resolved:
platform/chrome: cros_ec_ishtp: Fix UAF after unbinding driver
After unbinding the driver, another kthread `cros_ec_console_log_work`
is still accessing the device, resulting an UAF and crash.
The driver doesn't unregister the EC device in .remove() which should
shutdown sub-devices synchronously. Fix it. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/xe: Limit num_syncs to prevent oversized allocations
The exec and vm_bind ioctl allow userspace to specify an arbitrary
num_syncs value. Without bounds checking, a very large num_syncs
can force an excessively large allocation, leading to kernel warnings
from the page allocator as below.
Introduce DRM_XE_MAX_SYNCS (set to 1024) and reject any request
exceeding this limit.
"
------------[ cut here ]------------
WARNING: CPU: 0 PID: 1217 at mm/page_alloc.c:5124 __alloc_frozen_pages_noprof+0x2f8/0x2180 mm/page_alloc.c:5124
...
Call Trace:
<TASK>
alloc_pages_mpol+0xe4/0x330 mm/mempolicy.c:2416
___kmalloc_large_node+0xd8/0x110 mm/slub.c:4317
__kmalloc_large_node_noprof+0x18/0xe0 mm/slub.c:4348
__do_kmalloc_node mm/slub.c:4364 [inline]
__kmalloc_noprof+0x3d4/0x4b0 mm/slub.c:4388
kmalloc_noprof include/linux/slab.h:909 [inline]
kmalloc_array_noprof include/linux/slab.h:948 [inline]
xe_exec_ioctl+0xa47/0x1e70 drivers/gpu/drm/xe/xe_exec.c:158
drm_ioctl_kernel+0x1f1/0x3e0 drivers/gpu/drm/drm_ioctl.c:797
drm_ioctl+0x5e7/0xc50 drivers/gpu/drm/drm_ioctl.c:894
xe_drm_ioctl+0x10b/0x170 drivers/gpu/drm/xe/xe_device.c:224
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:598 [inline]
__se_sys_ioctl fs/ioctl.c:584 [inline]
__x64_sys_ioctl+0x18b/0x210 fs/ioctl.c:584
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xbb/0x380 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
...
"
v2: Add "Reported-by" and Cc stable kernels.
v3: Change XE_MAX_SYNCS from 64 to 1024. (Matt & Ashutosh)
v4: s/XE_MAX_SYNCS/DRM_XE_MAX_SYNCS/ (Matt)
v5: Do the check at the top of the exec func. (Matt)
(cherry picked from commit b07bac9bd708ec468cd1b8a5fe70ae2ac9b0a11c) |
| In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix to avoid updating compression context during writeback
Bai, Shuangpeng <sjb7183@psu.edu> reported a bug as below:
Oops: divide error: 0000 [#1] SMP KASAN PTI
CPU: 0 UID: 0 PID: 11441 Comm: syz.0.46 Not tainted 6.17.0 #1 PREEMPT(full)
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
RIP: 0010:f2fs_all_cluster_page_ready+0x106/0x550 fs/f2fs/compress.c:857
Call Trace:
<TASK>
f2fs_write_cache_pages fs/f2fs/data.c:3078 [inline]
__f2fs_write_data_pages fs/f2fs/data.c:3290 [inline]
f2fs_write_data_pages+0x1c19/0x3600 fs/f2fs/data.c:3317
do_writepages+0x38e/0x640 mm/page-writeback.c:2634
filemap_fdatawrite_wbc mm/filemap.c:386 [inline]
__filemap_fdatawrite_range mm/filemap.c:419 [inline]
file_write_and_wait_range+0x2ba/0x3e0 mm/filemap.c:794
f2fs_do_sync_file+0x6e6/0x1b00 fs/f2fs/file.c:294
generic_write_sync include/linux/fs.h:3043 [inline]
f2fs_file_write_iter+0x76e/0x2700 fs/f2fs/file.c:5259
new_sync_write fs/read_write.c:593 [inline]
vfs_write+0x7e9/0xe00 fs/read_write.c:686
ksys_write+0x19d/0x2d0 fs/read_write.c:738
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xf7/0x470 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The bug was triggered w/ below race condition:
fsync setattr ioctl
- f2fs_do_sync_file
- file_write_and_wait_range
- f2fs_write_cache_pages
: inode is non-compressed
: cc.cluster_size =
F2FS_I(inode)->i_cluster_size = 0
- tag_pages_for_writeback
- f2fs_setattr
- truncate_setsize
- f2fs_truncate
- f2fs_fileattr_set
- f2fs_setflags_common
- set_compress_context
: F2FS_I(inode)->i_cluster_size = 4
: set_inode_flag(inode, FI_COMPRESSED_FILE)
- f2fs_compressed_file
: return true
- f2fs_all_cluster_page_ready
: "pgidx % cc->cluster_size" trigger dividing 0 issue
Let's change as below to fix this issue:
- introduce a new atomic type variable .writeback in structure f2fs_inode_info
to track the number of threads which calling f2fs_write_cache_pages().
- use .i_sem lock to protect .writeback update.
- check .writeback before update compression context in f2fs_setflags_common()
to avoid race w/ ->writepages. |
| In the Linux kernel through 6.9, an untrusted hypervisor can inject virtual interrupts 0 and 14 at any point in time and can trigger the SIGFPE signal handler in userspace applications. This affects AMD SEV-SNP and AMD SEV-ES. |
| In the Linux kernel, the following vulnerability has been resolved:
ocfs2: fix kernel BUG in ocfs2_find_victim_chain
syzbot reported a kernel BUG in ocfs2_find_victim_chain() because the
`cl_next_free_rec` field of the allocation chain list (next free slot in
the chain list) is 0, triggring the BUG_ON(!cl->cl_next_free_rec)
condition in ocfs2_find_victim_chain() and panicking the kernel.
To fix this, an if condition is introduced in ocfs2_claim_suballoc_bits(),
just before calling ocfs2_find_victim_chain(), the code block in it being
executed when either of the following conditions is true:
1. `cl_next_free_rec` is equal to 0, indicating that there are no free
chains in the allocation chain list
2. `cl_next_free_rec` is greater than `cl_count` (the total number of
chains in the allocation chain list)
Either of them being true is indicative of the fact that there are no
chains left for usage.
This is addressed using ocfs2_error(), which prints
the error log for debugging purposes, rather than panicking the kernel. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: rtl818x: Fix potential memory leaks in rtl8180_init_rx_ring()
In rtl8180_init_rx_ring(), memory is allocated for skb packets and DMA
allocations in a loop. When an allocation fails, the previously
successful allocations are not freed on exit.
Fix that by jumping to err_free_rings label on error, which calls
rtl8180_free_rx_ring() to free the allocations. Remove the free of
rx_ring in rtl8180_init_rx_ring() error path, and set the freed
priv->rx_buf entry to null, to avoid double free. |
| In the Linux kernel, the following vulnerability has been resolved:
backlight: led-bl: Add devlink to supplier LEDs
LED Backlight is a consumer of one or multiple LED class devices, but
devlink is currently unable to create correct supplier-producer links when
the supplier is a class device. It creates instead a link where the
supplier is the parent of the expected device.
One consequence is that removal order is not correctly enforced.
Issues happen for example with the following sections in a device tree
overlay:
// An LED driver chip
pca9632@62 {
compatible = "nxp,pca9632";
reg = <0x62>;
// ...
addon_led_pwm: led-pwm@3 {
reg = <3>;
label = "addon:led:pwm";
};
};
backlight-addon {
compatible = "led-backlight";
leds = <&addon_led_pwm>;
brightness-levels = <255>;
default-brightness-level = <255>;
};
In this example, the devlink should be created between the backlight-addon
(consumer) and the pca9632@62 (supplier). Instead it is created between the
backlight-addon (consumer) and the parent of the pca9632@62, which is
typically the I2C bus adapter.
On removal of the above overlay, the LED driver can be removed before the
backlight device, resulting in:
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000010
...
Call trace:
led_put+0xe0/0x140
devm_led_release+0x6c/0x98
Another way to reproduce the bug without any device tree overlays is
unbinding the LED class device (pca9632@62) before unbinding the consumer
(backlight-addon):
echo 11-0062 >/sys/bus/i2c/drivers/leds-pca963x/unbind
echo ...backlight-dock >/sys/bus/platform/drivers/led-backlight/unbind
Fix by adding a devlink between the consuming led-backlight device and the
supplying LED device, as other drivers and subsystems do as well. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/vgem-fence: Fix potential deadlock on release
A timer that expires a vgem fence automatically in 10 seconds is now
released with timer_delete_sync() from fence->ops.release() called on last
dma_fence_put(). In some scenarios, it can run in IRQ context, which is
not safe unless TIMER_IRQSAFE is used. One potentially risky scenario was
demonstrated in Intel DRM CI trybot, BAT run on machine bat-adlp-6, while
working on new IGT subtests syncobj_timeline@stress-* as user space
replacements of some problematic test cases of a dma-fence-chain selftest
[1].
[117.004338] ================================
[117.004340] WARNING: inconsistent lock state
[117.004342] 6.17.0-rc7-CI_DRM_17270-g7644974e648c+ #1 Tainted: G S U
[117.004346] --------------------------------
[117.004347] inconsistent {HARDIRQ-ON-W} -> {IN-HARDIRQ-W} usage.
[117.004349] swapper/0/0 [HC1[1]:SC1[1]:HE0:SE0] takes:
[117.004352] ffff888138f86aa8 ((&fence->timer)){?.-.}-{0:0}, at: __timer_delete_sync+0x4b/0x190
[117.004361] {HARDIRQ-ON-W} state was registered at:
[117.004363] lock_acquire+0xc4/0x2e0
[117.004366] call_timer_fn+0x80/0x2a0
[117.004368] __run_timers+0x231/0x310
[117.004370] run_timer_softirq+0x76/0xe0
[117.004372] handle_softirqs+0xd4/0x4d0
[117.004375] __irq_exit_rcu+0x13f/0x160
[117.004377] irq_exit_rcu+0xe/0x20
[117.004379] sysvec_apic_timer_interrupt+0xa0/0xc0
[117.004382] asm_sysvec_apic_timer_interrupt+0x1b/0x20
[117.004385] cpuidle_enter_state+0x12b/0x8a0
[117.004388] cpuidle_enter+0x2e/0x50
[117.004393] call_cpuidle+0x22/0x60
[117.004395] do_idle+0x1fd/0x260
[117.004398] cpu_startup_entry+0x29/0x30
[117.004401] start_secondary+0x12d/0x160
[117.004404] common_startup_64+0x13e/0x141
[117.004407] irq event stamp: 2282669
[117.004409] hardirqs last enabled at (2282668): [<ffffffff8289db71>] _raw_spin_unlock_irqrestore+0x51/0x80
[117.004414] hardirqs last disabled at (2282669): [<ffffffff82882021>] sysvec_irq_work+0x11/0xc0
[117.004419] softirqs last enabled at (2254702): [<ffffffff8289fd00>] __do_softirq+0x10/0x18
[117.004423] softirqs last disabled at (2254725): [<ffffffff813d4ddf>] __irq_exit_rcu+0x13f/0x160
[117.004426]
other info that might help us debug this:
[117.004429] Possible unsafe locking scenario:
[117.004432] CPU0
[117.004433] ----
[117.004434] lock((&fence->timer));
[117.004436] <Interrupt>
[117.004438] lock((&fence->timer));
[117.004440]
*** DEADLOCK ***
[117.004443] 1 lock held by swapper/0/0:
[117.004445] #0: ffffc90000003d50 ((&fence->timer)){?.-.}-{0:0}, at: call_timer_fn+0x7a/0x2a0
[117.004450]
stack backtrace:
[117.004453] CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Tainted: G S U 6.17.0-rc7-CI_DRM_17270-g7644974e648c+ #1 PREEMPT(voluntary)
[117.004455] Tainted: [S]=CPU_OUT_OF_SPEC, [U]=USER
[117.004455] Hardware name: Intel Corporation Alder Lake Client Platform/AlderLake-P DDR4 RVP, BIOS RPLPFWI1.R00.4035.A00.2301200723 01/20/2023
[117.004456] Call Trace:
[117.004456] <IRQ>
[117.004457] dump_stack_lvl+0x91/0xf0
[117.004460] dump_stack+0x10/0x20
[117.004461] print_usage_bug.part.0+0x260/0x360
[117.004463] mark_lock+0x76e/0x9c0
[117.004465] ? register_lock_class+0x48/0x4a0
[117.004467] __lock_acquire+0xbc3/0x2860
[117.004469] lock_acquire+0xc4/0x2e0
[117.004470] ? __timer_delete_sync+0x4b/0x190
[117.004472] ? __timer_delete_sync+0x4b/0x190
[117.004473] __timer_delete_sync+0x68/0x190
[117.004474] ? __timer_delete_sync+0x4b/0x190
[117.004475] timer_delete_sync+0x10/0x20
[117.004476] vgem_fence_release+0x19/0x30 [vgem]
[117.004478] dma_fence_release+0xc1/0x3b0
[117.004480] ? dma_fence_release+0xa1/0x3b0
[117.004481] dma_fence_chain_release+0xe7/0x130
[117.004483] dma_fence_release+0xc1/0x3b0
[117.004484] ? _raw_spin_unlock_irqrestore+0x27/0x80
[117.004485] dma_fence_chain_irq_work+0x59/0x80
[117.004487] irq_work_single+0x75/0xa0
[117.004490] irq_work_r
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
block: Use RCU in blk_mq_[un]quiesce_tagset() instead of set->tag_list_lock
blk_mq_{add,del}_queue_tag_set() functions add and remove queues from
tagset, the functions make sure that tagset and queues are marked as
shared when two or more queues are attached to the same tagset.
Initially a tagset starts as unshared and when the number of added
queues reaches two, blk_mq_add_queue_tag_set() marks it as shared along
with all the queues attached to it. When the number of attached queues
drops to 1 blk_mq_del_queue_tag_set() need to mark both the tagset and
the remaining queues as unshared.
Both functions need to freeze current queues in tagset before setting on
unsetting BLK_MQ_F_TAG_QUEUE_SHARED flag. While doing so, both functions
hold set->tag_list_lock mutex, which makes sense as we do not want
queues to be added or deleted in the process. This used to work fine
until commit 98d81f0df70c ("nvme: use blk_mq_[un]quiesce_tagset")
made the nvme driver quiesce tagset instead of quiscing individual
queues. blk_mq_quiesce_tagset() does the job and quiesce the queues in
set->tag_list while holding set->tag_list_lock also.
This results in deadlock between two threads with these stacktraces:
__schedule+0x47c/0xbb0
? timerqueue_add+0x66/0xb0
schedule+0x1c/0xa0
schedule_preempt_disabled+0xa/0x10
__mutex_lock.constprop.0+0x271/0x600
blk_mq_quiesce_tagset+0x25/0xc0
nvme_dev_disable+0x9c/0x250
nvme_timeout+0x1fc/0x520
blk_mq_handle_expired+0x5c/0x90
bt_iter+0x7e/0x90
blk_mq_queue_tag_busy_iter+0x27e/0x550
? __blk_mq_complete_request_remote+0x10/0x10
? __blk_mq_complete_request_remote+0x10/0x10
? __call_rcu_common.constprop.0+0x1c0/0x210
blk_mq_timeout_work+0x12d/0x170
process_one_work+0x12e/0x2d0
worker_thread+0x288/0x3a0
? rescuer_thread+0x480/0x480
kthread+0xb8/0xe0
? kthread_park+0x80/0x80
ret_from_fork+0x2d/0x50
? kthread_park+0x80/0x80
ret_from_fork_asm+0x11/0x20
__schedule+0x47c/0xbb0
? xas_find+0x161/0x1a0
schedule+0x1c/0xa0
blk_mq_freeze_queue_wait+0x3d/0x70
? destroy_sched_domains_rcu+0x30/0x30
blk_mq_update_tag_set_shared+0x44/0x80
blk_mq_exit_queue+0x141/0x150
del_gendisk+0x25a/0x2d0
nvme_ns_remove+0xc9/0x170
nvme_remove_namespaces+0xc7/0x100
nvme_remove+0x62/0x150
pci_device_remove+0x23/0x60
device_release_driver_internal+0x159/0x200
unbind_store+0x99/0xa0
kernfs_fop_write_iter+0x112/0x1e0
vfs_write+0x2b1/0x3d0
ksys_write+0x4e/0xb0
do_syscall_64+0x5b/0x160
entry_SYSCALL_64_after_hwframe+0x4b/0x53
The top stacktrace is showing nvme_timeout() called to handle nvme
command timeout. timeout handler is trying to disable the controller and
as a first step, it needs to blk_mq_quiesce_tagset() to tell blk-mq not
to call queue callback handlers. The thread is stuck waiting for
set->tag_list_lock as it tries to walk the queues in set->tag_list.
The lock is held by the second thread in the bottom stack which is
waiting for one of queues to be frozen. The queue usage counter will
drop to zero after nvme_timeout() finishes, and this will not happen
because the thread will wait for this mutex forever.
Given that [un]quiescing queue is an operation that does not need to
sleep, update blk_mq_[un]quiesce_tagset() to use RCU instead of taking
set->tag_list_lock, update blk_mq_{add,del}_queue_tag_set() to use RCU
safe list operations. Also, delete INIT_LIST_HEAD(&q->tag_set_list)
in blk_mq_del_queue_tag_set() because we can not re-initialize it while
the list is being traversed under RCU. The deleted queue will not be
added/deleted to/from a tagset and it will be freed in blk_free_queue()
after the end of RCU grace period. |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: Free special fields when update [lru_,]percpu_hash maps
As [lru_,]percpu_hash maps support BPF_KPTR_{REF,PERCPU}, missing
calls to 'bpf_obj_free_fields()' in 'pcpu_copy_value()' could cause the
memory referenced by BPF_KPTR_{REF,PERCPU} fields to be held until the
map gets freed.
Fix this by calling 'bpf_obj_free_fields()' after
'copy_map_value[,_long]()' in 'pcpu_copy_value()'. |
