Security Vulnerabilities
- CVEs Published In February 2025
In the Linux kernel, the following vulnerability has been resolved:
block: Fix potential deadlock in blk_ia_range_sysfs_show()
When being read, a sysfs attribute is already protected against removal
with the kobject node active reference counter. As a result, in
blk_ia_range_sysfs_show(), there is no need to take the queue sysfs
lock when reading the value of a range attribute. Using the queue sysfs
lock in this function creates a potential deadlock situation with the
disk removal, something that a lockdep signals with a splat when the
device is removed:
[ 760.703551] Possible unsafe locking scenario:
[ 760.703551]
[ 760.703554] CPU0 CPU1
[ 760.703556] ---- ----
[ 760.703558] lock(&q->sysfs_lock);
[ 760.703565] lock(kn->active#385);
[ 760.703573] lock(&q->sysfs_lock);
[ 760.703579] lock(kn->active#385);
[ 760.703587]
[ 760.703587] *** DEADLOCK ***
Solve this by removing the mutex_lock()/mutex_unlock() calls from
blk_ia_range_sysfs_show().
In the Linux kernel, the following vulnerability has been resolved:
dlm: fix plock invalid read
This patch fixes an invalid read showed by KASAN. A unlock will allocate a
"struct plock_op" and a followed send_op() will append it to a global
send_list data structure. In some cases a followed dev_read() moves it
to recv_list and dev_write() will cast it to "struct plock_xop" and access
fields which are only available in those structures. At this point an
invalid read happens by accessing those fields.
To fix this issue the "callback" field is moved to "struct plock_op" to
indicate that a cast to "plock_xop" is allowed and does the additional
"plock_xop" handling if set.
Example of the KASAN output which showed the invalid read:
[ 2064.296453] ==================================================================
[ 2064.304852] BUG: KASAN: slab-out-of-bounds in dev_write+0x52b/0x5a0 [dlm]
[ 2064.306491] Read of size 8 at addr ffff88800ef227d8 by task dlm_controld/7484
[ 2064.308168]
[ 2064.308575] CPU: 0 PID: 7484 Comm: dlm_controld Kdump: loaded Not tainted 5.14.0+ #9
[ 2064.310292] Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011
[ 2064.311618] Call Trace:
[ 2064.312218] dump_stack_lvl+0x56/0x7b
[ 2064.313150] print_address_description.constprop.8+0x21/0x150
[ 2064.314578] ? dev_write+0x52b/0x5a0 [dlm]
[ 2064.315610] ? dev_write+0x52b/0x5a0 [dlm]
[ 2064.316595] kasan_report.cold.14+0x7f/0x11b
[ 2064.317674] ? dev_write+0x52b/0x5a0 [dlm]
[ 2064.318687] dev_write+0x52b/0x5a0 [dlm]
[ 2064.319629] ? dev_read+0x4a0/0x4a0 [dlm]
[ 2064.320713] ? bpf_lsm_kernfs_init_security+0x10/0x10
[ 2064.321926] vfs_write+0x17e/0x930
[ 2064.322769] ? __fget_light+0x1aa/0x220
[ 2064.323753] ksys_write+0xf1/0x1c0
[ 2064.324548] ? __ia32_sys_read+0xb0/0xb0
[ 2064.325464] do_syscall_64+0x3a/0x80
[ 2064.326387] entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 2064.327606] RIP: 0033:0x7f807e4ba96f
[ 2064.328470] Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 39 87 f8 ff 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 7c 87 f8 ff 48
[ 2064.332902] RSP: 002b:00007ffd50cfe6e0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
[ 2064.334658] RAX: ffffffffffffffda RBX: 000055cc3886eb30 RCX: 00007f807e4ba96f
[ 2064.336275] RDX: 0000000000000040 RSI: 00007ffd50cfe7e0 RDI: 0000000000000010
[ 2064.337980] RBP: 00007ffd50cfe7e0 R08: 0000000000000000 R09: 0000000000000001
[ 2064.339560] R10: 000055cc3886eb30 R11: 0000000000000293 R12: 000055cc3886eb80
[ 2064.341237] R13: 000055cc3886eb00 R14: 000055cc3886f590 R15: 0000000000000001
[ 2064.342857]
[ 2064.343226] Allocated by task 12438:
[ 2064.344057] kasan_save_stack+0x1c/0x40
[ 2064.345079] __kasan_kmalloc+0x84/0xa0
[ 2064.345933] kmem_cache_alloc_trace+0x13b/0x220
[ 2064.346953] dlm_posix_unlock+0xec/0x720 [dlm]
[ 2064.348811] do_lock_file_wait.part.32+0xca/0x1d0
[ 2064.351070] fcntl_setlk+0x281/0xbc0
[ 2064.352879] do_fcntl+0x5e4/0xfe0
[ 2064.354657] __x64_sys_fcntl+0x11f/0x170
[ 2064.356550] do_syscall_64+0x3a/0x80
[ 2064.358259] entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 2064.360745]
[ 2064.361511] Last potentially related work creation:
[ 2064.363957] kasan_save_stack+0x1c/0x40
[ 2064.365811] __kasan_record_aux_stack+0xaf/0xc0
[ 2064.368100] call_rcu+0x11b/0xf70
[ 2064.369785] dlm_process_incoming_buffer+0x47d/0xfd0 [dlm]
[ 2064.372404] receive_from_sock+0x290/0x770 [dlm]
[ 2064.374607] process_recv_sockets+0x32/0x40 [dlm]
[ 2064.377290] process_one_work+0x9a8/0x16e0
[ 2064.379357] worker_thread+0x87/0xbf0
[ 2064.381188] kthread+0x3ac/0x490
[ 2064.383460] ret_from_fork+0x22/0x30
[ 2064.385588]
[ 2064.386518] Second to last potentially related work creation:
[ 2064.389219] kasan_save_stack+0x1c/0x40
[ 2064.391043] __kasan_record_aux_stack+0xaf/0xc0
[ 2064.393303] call_rcu+0x11b/0xf70
[ 2064.394885] dlm_process_incoming_buffer+0x47d/0xfd0 [dlm]
[ 2064.397694] receive_from_sock+0x290/0x770
---truncated---
In the Linux kernel, the following vulnerability has been resolved:
ext4: fix memory leak in parse_apply_sb_mount_options()
If processing the on-disk mount options fails after any memory was
allocated in the ext4_fs_context, e.g. s_qf_names, then this memory is
leaked. Fix this by calling ext4_fc_free() instead of kfree() directly.
Reproducer:
mkfs.ext4 -F /dev/vdc
tune2fs /dev/vdc -E mount_opts=usrjquota=file
echo clear > /sys/kernel/debug/kmemleak
mount /dev/vdc /vdc
echo scan > /sys/kernel/debug/kmemleak
sleep 5
echo scan > /sys/kernel/debug/kmemleak
cat /sys/kernel/debug/kmemleak
In the Linux kernel, the following vulnerability has been resolved:
ext4: fix bug_on in __es_tree_search
Hulk Robot reported a BUG_ON:
==================================================================
kernel BUG at fs/ext4/extents_status.c:199!
[...]
RIP: 0010:ext4_es_end fs/ext4/extents_status.c:199 [inline]
RIP: 0010:__es_tree_search+0x1e0/0x260 fs/ext4/extents_status.c:217
[...]
Call Trace:
ext4_es_cache_extent+0x109/0x340 fs/ext4/extents_status.c:766
ext4_cache_extents+0x239/0x2e0 fs/ext4/extents.c:561
ext4_find_extent+0x6b7/0xa20 fs/ext4/extents.c:964
ext4_ext_map_blocks+0x16b/0x4b70 fs/ext4/extents.c:4384
ext4_map_blocks+0xe26/0x19f0 fs/ext4/inode.c:567
ext4_getblk+0x320/0x4c0 fs/ext4/inode.c:980
ext4_bread+0x2d/0x170 fs/ext4/inode.c:1031
ext4_quota_read+0x248/0x320 fs/ext4/super.c:6257
v2_read_header+0x78/0x110 fs/quota/quota_v2.c:63
v2_check_quota_file+0x76/0x230 fs/quota/quota_v2.c:82
vfs_load_quota_inode+0x5d1/0x1530 fs/quota/dquot.c:2368
dquot_enable+0x28a/0x330 fs/quota/dquot.c:2490
ext4_quota_enable fs/ext4/super.c:6137 [inline]
ext4_enable_quotas+0x5d7/0x960 fs/ext4/super.c:6163
ext4_fill_super+0xa7c9/0xdc00 fs/ext4/super.c:4754
mount_bdev+0x2e9/0x3b0 fs/super.c:1158
mount_fs+0x4b/0x1e4 fs/super.c:1261
[...]
==================================================================
Above issue may happen as follows:
-------------------------------------
ext4_fill_super
ext4_enable_quotas
ext4_quota_enable
ext4_iget
__ext4_iget
ext4_ext_check_inode
ext4_ext_check
__ext4_ext_check
ext4_valid_extent_entries
Check for overlapping extents does't take effect
dquot_enable
vfs_load_quota_inode
v2_check_quota_file
v2_read_header
ext4_quota_read
ext4_bread
ext4_getblk
ext4_map_blocks
ext4_ext_map_blocks
ext4_find_extent
ext4_cache_extents
ext4_es_cache_extent
ext4_es_cache_extent
__es_tree_search
ext4_es_end
BUG_ON(es->es_lblk + es->es_len < es->es_lblk)
The error ext4 extents is as follows:
0af3 0300 0400 0000 00000000 extent_header
00000000 0100 0000 12000000 extent1
00000000 0100 0000 18000000 extent2
02000000 0400 0000 14000000 extent3
In the ext4_valid_extent_entries function,
if prev is 0, no error is returned even if lblock<=prev.
This was intended to skip the check on the first extent, but
in the error image above, prev=0+1-1=0 when checking the second extent,
so even though lblock<=prev, the function does not return an error.
As a result, bug_ON occurs in __es_tree_search and the system panics.
To solve this problem, we only need to check that:
1. The lblock of the first extent is not less than 0.
2. The lblock of the next extent is not less than
the next block of the previous extent.
The same applies to extent_idx.
In the Linux kernel, the following vulnerability has been resolved:
tracing: Fix potential double free in create_var_ref()
In create_var_ref(), init_var_ref() is called to initialize the fields
of variable ref_field, which is allocated in the previous function call
to create_hist_field(). Function init_var_ref() allocates the
corresponding fields such as ref_field->system, but frees these fields
when the function encounters an error. The caller later calls
destroy_hist_field() to conduct error handling, which frees the fields
and the variable itself. This results in double free of the fields which
are already freed in the previous function.
Fix this by storing NULL to the corresponding fields when they are freed
in init_var_ref().
In the Linux kernel, the following vulnerability has been resolved:
bfq: Make sure bfqg for which we are queueing requests is online
Bios queued into BFQ IO scheduler can be associated with a cgroup that
was already offlined. This may then cause insertion of this bfq_group
into a service tree. But this bfq_group will get freed as soon as last
bio associated with it is completed leading to use after free issues for
service tree users. Fix the problem by making sure we always operate on
online bfq_group. If the bfq_group associated with the bio is not
online, we pick the first online parent.
In the Linux kernel, the following vulnerability has been resolved:
bfq: Avoid merging queues with different parents
It can happen that the parent of a bfqq changes between the moment we
decide two queues are worth to merge (and set bic->stable_merge_bfqq)
and the moment bfq_setup_merge() is called. This can happen e.g. because
the process submitted IO for a different cgroup and thus bfqq got
reparented. It can even happen that the bfqq we are merging with has
parent cgroup that is already offline and going to be destroyed in which
case the merge can lead to use-after-free issues such as:
BUG: KASAN: use-after-free in __bfq_deactivate_entity+0x9cb/0xa50
Read of size 8 at addr ffff88800693c0c0 by task runc:[2:INIT]/10544
CPU: 0 PID: 10544 Comm: runc:[2:INIT] Tainted: G E 5.15.2-0.g5fb85fd-default #1 openSUSE Tumbleweed (unreleased) f1f3b891c72369aebecd2e43e4641a6358867c70
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a-rebuilt.opensuse.org 04/01/2014
Call Trace:
<IRQ>
dump_stack_lvl+0x46/0x5a
print_address_description.constprop.0+0x1f/0x140
? __bfq_deactivate_entity+0x9cb/0xa50
kasan_report.cold+0x7f/0x11b
? __bfq_deactivate_entity+0x9cb/0xa50
__bfq_deactivate_entity+0x9cb/0xa50
? update_curr+0x32f/0x5d0
bfq_deactivate_entity+0xa0/0x1d0
bfq_del_bfqq_busy+0x28a/0x420
? resched_curr+0x116/0x1d0
? bfq_requeue_bfqq+0x70/0x70
? check_preempt_wakeup+0x52b/0xbc0
__bfq_bfqq_expire+0x1a2/0x270
bfq_bfqq_expire+0xd16/0x2160
? try_to_wake_up+0x4ee/0x1260
? bfq_end_wr_async_queues+0xe0/0xe0
? _raw_write_unlock_bh+0x60/0x60
? _raw_spin_lock_irq+0x81/0xe0
bfq_idle_slice_timer+0x109/0x280
? bfq_dispatch_request+0x4870/0x4870
__hrtimer_run_queues+0x37d/0x700
? enqueue_hrtimer+0x1b0/0x1b0
? kvm_clock_get_cycles+0xd/0x10
? ktime_get_update_offsets_now+0x6f/0x280
hrtimer_interrupt+0x2c8/0x740
Fix the problem by checking that the parent of the two bfqqs we are
merging in bfq_setup_merge() is the same.
In the Linux kernel, the following vulnerability has been resolved:
bfq: Update cgroup information before merging bio
When the process is migrated to a different cgroup (or in case of
writeback just starts submitting bios associated with a different
cgroup) bfq_merge_bio() can operate with stale cgroup information in
bic. Thus the bio can be merged to a request from a different cgroup or
it can result in merging of bfqqs for different cgroups or bfqqs of
already dead cgroups and causing possible use-after-free issues. Fix the
problem by updating cgroup information in bfq_merge_bio().
In the Linux kernel, the following vulnerability has been resolved:
ext4: fix race condition between ext4_write and ext4_convert_inline_data
Hulk Robot reported a BUG_ON:
==================================================================
EXT4-fs error (device loop3): ext4_mb_generate_buddy:805: group 0,
block bitmap and bg descriptor inconsistent: 25 vs 31513 free clusters
kernel BUG at fs/ext4/ext4_jbd2.c:53!
invalid opcode: 0000 [#1] SMP KASAN PTI
CPU: 0 PID: 25371 Comm: syz-executor.3 Not tainted 5.10.0+ #1
RIP: 0010:ext4_put_nojournal fs/ext4/ext4_jbd2.c:53 [inline]
RIP: 0010:__ext4_journal_stop+0x10e/0x110 fs/ext4/ext4_jbd2.c:116
[...]
Call Trace:
ext4_write_inline_data_end+0x59a/0x730 fs/ext4/inline.c:795
generic_perform_write+0x279/0x3c0 mm/filemap.c:3344
ext4_buffered_write_iter+0x2e3/0x3d0 fs/ext4/file.c:270
ext4_file_write_iter+0x30a/0x11c0 fs/ext4/file.c:520
do_iter_readv_writev+0x339/0x3c0 fs/read_write.c:732
do_iter_write+0x107/0x430 fs/read_write.c:861
vfs_writev fs/read_write.c:934 [inline]
do_pwritev+0x1e5/0x380 fs/read_write.c:1031
[...]
==================================================================
Above issue may happen as follows:
cpu1 cpu2
__________________________|__________________________
do_pwritev
vfs_writev
do_iter_write
ext4_file_write_iter
ext4_buffered_write_iter
generic_perform_write
ext4_da_write_begin
vfs_fallocate
ext4_fallocate
ext4_convert_inline_data
ext4_convert_inline_data_nolock
ext4_destroy_inline_data_nolock
clear EXT4_STATE_MAY_INLINE_DATA
ext4_map_blocks
ext4_ext_map_blocks
ext4_mb_new_blocks
ext4_mb_regular_allocator
ext4_mb_good_group_nolock
ext4_mb_init_group
ext4_mb_init_cache
ext4_mb_generate_buddy --> error
ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA)
ext4_restore_inline_data
set EXT4_STATE_MAY_INLINE_DATA
ext4_block_write_begin
ext4_da_write_end
ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA)
ext4_write_inline_data_end
handle=NULL
ext4_journal_stop(handle)
__ext4_journal_stop
ext4_put_nojournal(handle)
ref_cnt = (unsigned long)handle
BUG_ON(ref_cnt == 0) ---> BUG_ON
The lock held by ext4_convert_inline_data is xattr_sem, but the lock
held by generic_perform_write is i_rwsem. Therefore, the two locks can
be concurrent.
To solve above issue, we add inode_lock() for ext4_convert_inline_data().
At the same time, move ext4_convert_inline_data() in front of
ext4_punch_hole(), remove similar handling from ext4_punch_hole().
In the Linux kernel, the following vulnerability has been resolved:
ipmi:ipmb: Fix refcount leak in ipmi_ipmb_probe
of_parse_phandle() returns a node pointer with refcount
incremented, we should use of_node_put() on it when done.
Add missing of_node_put() to avoid refcount leak.