Linux: >> Linux Kernel >> 2.6.19.5 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
md: fix a crash in mempool_free
There's a crash in mempool_free when running the lvm test
shell/lvchange-rebuild-raid.sh.
The reason for the crash is this:
* super_written calls atomic_dec_and_test(&mddev->pending_writes) and
wake_up(&mddev->sb_wait). Then it calls rdev_dec_pending(rdev, mddev)
and bio_put(bio).
* so, the process that waited on sb_wait and that is woken up is racing
with bio_put(bio).
* if the process wins the race, it calls bioset_exit before bio_put(bio)
is executed.
* bio_put(bio) attempts to free a bio into a destroyed bio set - causing
a crash in mempool_free.
We fix this bug by moving bio_put before atomic_dec_and_test.
We also move rdev_dec_pending before atomic_dec_and_test as suggested by
Neil Brown.
The function md_end_flush has a similar bug - we must call bio_put before
we decrement the number of in-progress bios.
BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor write access in kernel mode
#PF: error_code(0x0002) - not-present page
PGD 11557f0067 P4D 11557f0067 PUD 0
Oops: 0002 [#1] PREEMPT SMP
CPU: 0 PID: 73 Comm: kworker/0:1 Not tainted 6.1.0-rc3 #5
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014
Workqueue: kdelayd flush_expired_bios [dm_delay]
RIP: 0010:mempool_free+0x47/0x80
Code: 48 89 ef 5b 5d ff e0 f3 c3 48 89 f7 e8 32 45 3f 00 48 63 53 08 48 89 c6 3b 53 04 7d 2d 48 8b 43 10 8d 4a 01 48 89 df 89 4b 08 <48> 89 2c d0 e8 b0 45 3f 00 48 8d 7b 30 5b 5d 31 c9 ba 01 00 00 00
RSP: 0018:ffff88910036bda8 EFLAGS: 00010093
RAX: 0000000000000000 RBX: ffff8891037b65d8 RCX: 0000000000000001
RDX: 0000000000000000 RSI: 0000000000000202 RDI: ffff8891037b65d8
RBP: ffff8891447ba240 R08: 0000000000012908 R09: 00000000003d0900
R10: 0000000000000000 R11: 0000000000173544 R12: ffff889101a14000
R13: ffff8891562ac300 R14: ffff889102b41440 R15: ffffe8ffffa00d05
FS: 0000000000000000(0000) GS:ffff88942fa00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 0000001102e99000 CR4: 00000000000006b0
Call Trace:
<TASK>
clone_endio+0xf4/0x1c0 [dm_mod]
clone_endio+0xf4/0x1c0 [dm_mod]
__submit_bio+0x76/0x120
submit_bio_noacct_nocheck+0xb6/0x2a0
flush_expired_bios+0x28/0x2f [dm_delay]
process_one_work+0x1b4/0x300
worker_thread+0x45/0x3e0
? rescuer_thread+0x380/0x380
kthread+0xc2/0x100
? kthread_complete_and_exit+0x20/0x20
ret_from_fork+0x1f/0x30
</TASK>
Modules linked in: brd dm_delay dm_raid dm_mod af_packet uvesafb cfbfillrect cfbimgblt cn cfbcopyarea fb font fbdev tun autofs4 binfmt_misc configfs ipv6 virtio_rng virtio_balloon rng_core virtio_net pcspkr net_failover failover qemu_fw_cfg button mousedev raid10 raid456 libcrc32c async_raid6_recov async_memcpy async_pq raid6_pq async_xor xor async_tx raid1 raid0 md_mod sd_mod t10_pi crc64_rocksoft crc64 virtio_scsi scsi_mod evdev psmouse bsg scsi_common [last unloaded: brd]
CR2: 0000000000000000
---[ end trace 0000000000000000 ]---
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-18
In the Linux kernel, the following vulnerability has been resolved:
USB: fix memory leak with using debugfs_lookup()
When calling debugfs_lookup() the result must have dput() called on it,
otherwise the memory will leak over time. To make things simpler, just
call debugfs_lookup_and_remove() instead which handles all of the logic at
once.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-17
In the Linux kernel, the following vulnerability has been resolved:
kernel/fail_function: fix memory leak with using debugfs_lookup()
When calling debugfs_lookup() the result must have dput() called on it,
otherwise the memory will leak over time. To make things simpler, just
call debugfs_lookup_and_remove() instead which handles all of the logic
at once.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-17
In the Linux kernel, the following vulnerability has been resolved:
btrfs: fix BUG_ON condition in btrfs_cancel_balance
Pausing and canceling balance can race to interrupt balance lead to BUG_ON
panic in btrfs_cancel_balance. The BUG_ON condition in btrfs_cancel_balance
does not take this race scenario into account.
However, the race condition has no other side effects. We can fix that.
Reproducing it with panic trace like this:
kernel BUG at fs/btrfs/volumes.c:4618!
RIP: 0010:btrfs_cancel_balance+0x5cf/0x6a0
Call Trace:
<TASK>
? do_nanosleep+0x60/0x120
? hrtimer_nanosleep+0xb7/0x1a0
? sched_core_clone_cookie+0x70/0x70
btrfs_ioctl_balance_ctl+0x55/0x70
btrfs_ioctl+0xa46/0xd20
__x64_sys_ioctl+0x7d/0xa0
do_syscall_64+0x38/0x80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
Race scenario as follows:
> mutex_unlock(&fs_info->balance_mutex);
> --------------------
> .......issue pause and cancel req in another thread
> --------------------
> ret = __btrfs_balance(fs_info);
>
> mutex_lock(&fs_info->balance_mutex);
> if (ret == -ECANCELED && atomic_read(&fs_info->balance_pause_req)) {
> btrfs_info(fs_info, "balance: paused");
> btrfs_exclop_balance(fs_info, BTRFS_EXCLOP_BALANCE_PAUSED);
> }
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-17
In the Linux kernel, the following vulnerability has been resolved:
fs: dlm: fix race in lowcomms
This patch fixes a race between queue_work() in
_dlm_lowcomms_commit_msg() and srcu_read_unlock(). The queue_work() can
take the final reference of a dlm_msg and so msg->idx can contain
garbage which is signaled by the following warning:
[ 676.237050] ------------[ cut here ]------------
[ 676.237052] WARNING: CPU: 0 PID: 1060 at include/linux/srcu.h:189 dlm_lowcomms_commit_msg+0x41/0x50
[ 676.238945] Modules linked in: dlm_locktorture torture rpcsec_gss_krb5 intel_rapl_msr intel_rapl_common iTCO_wdt iTCO_vendor_support qxl kvm_intel drm_ttm_helper vmw_vsock_virtio_transport kvm vmw_vsock_virtio_transport_common ttm irqbypass crc32_pclmul joydev crc32c_intel serio_raw drm_kms_helper vsock virtio_scsi virtio_console virtio_balloon snd_pcm drm syscopyarea sysfillrect sysimgblt snd_timer fb_sys_fops i2c_i801 lpc_ich snd i2c_smbus soundcore pcspkr
[ 676.244227] CPU: 0 PID: 1060 Comm: lock_torture_wr Not tainted 5.19.0-rc3+ #1546
[ 676.245216] Hardware name: Red Hat KVM/RHEL-AV, BIOS 1.16.0-2.module+el8.7.0+15506+033991b0 04/01/2014
[ 676.246460] RIP: 0010:dlm_lowcomms_commit_msg+0x41/0x50
[ 676.247132] Code: fe ff ff ff 75 24 48 c7 c6 bd 0f 49 bb 48 c7 c7 38 7c 01 bd e8 00 e7 ca ff 89 de 48 c7 c7 60 78 01 bd e8 42 3d cd ff 5b 5d c3 <0f> 0b eb d8 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 48
[ 676.249253] RSP: 0018:ffffa401c18ffc68 EFLAGS: 00010282
[ 676.249855] RAX: 0000000000000001 RBX: 00000000ffff8b76 RCX: 0000000000000006
[ 676.250713] RDX: 0000000000000000 RSI: ffffffffbccf3a10 RDI: ffffffffbcc7b62e
[ 676.251610] RBP: ffffa401c18ffc70 R08: 0000000000000001 R09: 0000000000000001
[ 676.252481] R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000005
[ 676.253421] R13: ffff8b76786ec370 R14: ffff8b76786ec370 R15: ffff8b76786ec480
[ 676.254257] FS: 0000000000000000(0000) GS:ffff8b7777800000(0000) knlGS:0000000000000000
[ 676.255239] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 676.255897] CR2: 00005590205d88b8 CR3: 000000017656c003 CR4: 0000000000770ee0
[ 676.256734] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 676.257567] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 676.258397] PKRU: 55555554
[ 676.258729] Call Trace:
[ 676.259063] <TASK>
[ 676.259354] dlm_midcomms_commit_mhandle+0xcc/0x110
[ 676.259964] queue_bast+0x8b/0xb0
[ 676.260423] grant_pending_locks+0x166/0x1b0
[ 676.261007] _unlock_lock+0x75/0x90
[ 676.261469] unlock_lock.isra.57+0x62/0xa0
[ 676.262009] dlm_unlock+0x21e/0x330
[ 676.262457] ? lock_torture_stats+0x80/0x80 [dlm_locktorture]
[ 676.263183] torture_unlock+0x5a/0x90 [dlm_locktorture]
[ 676.263815] ? preempt_count_sub+0xba/0x100
[ 676.264361] ? complete+0x1d/0x60
[ 676.264777] lock_torture_writer+0xb8/0x150 [dlm_locktorture]
[ 676.265555] kthread+0x10a/0x130
[ 676.266007] ? kthread_complete_and_exit+0x20/0x20
[ 676.266616] ret_from_fork+0x22/0x30
[ 676.267097] </TASK>
[ 676.267381] irq event stamp: 9579855
[ 676.267824] hardirqs last enabled at (9579863): [<ffffffffbb14e6f8>] __up_console_sem+0x58/0x60
[ 676.268896] hardirqs last disabled at (9579872): [<ffffffffbb14e6dd>] __up_console_sem+0x3d/0x60
[ 676.270008] softirqs last enabled at (9579798): [<ffffffffbc200349>] __do_softirq+0x349/0x4c7
[ 676.271438] softirqs last disabled at (9579897): [<ffffffffbb0d54c0>] irq_exit_rcu+0xb0/0xf0
[ 676.272796] ---[ end trace 0000000000000000 ]---
I reproduced this warning with dlm_locktorture test which is currently
not upstream. However this patch fix the issue by make a additional
refcount between dlm_lowcomms_new_msg() and dlm_lowcomms_commit_msg().
In case of the race the kref_put() in dlm_lowcomms_commit_msg() will be
the final put.
CVSS Score
4.7
EPSS Score
0.0
Published
2025-09-17
In the Linux kernel, the following vulnerability has been resolved:
nilfs2: do not write dirty data after degenerating to read-only
According to syzbot's report, mark_buffer_dirty() called from
nilfs_segctor_do_construct() outputs a warning with some patterns after
nilfs2 detects metadata corruption and degrades to read-only mode.
After such read-only degeneration, page cache data may be cleared through
nilfs_clear_dirty_page() which may also clear the uptodate flag for their
buffer heads. However, even after the degeneration, log writes are still
performed by unmount processing etc., which causes mark_buffer_dirty() to
be called for buffer heads without the "uptodate" flag and causes the
warning.
Since any writes should not be done to a read-only file system in the
first place, this fixes the warning in mark_buffer_dirty() by letting
nilfs_segctor_do_construct() abort early if in read-only mode.
This also changes the retry check of nilfs_segctor_write_out() to avoid
unnecessary log write retries if it detects -EROFS that
nilfs_segctor_do_construct() returned.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-17
In the Linux kernel, the following vulnerability has been resolved:
powercap: intel_rapl: fix UBSAN shift-out-of-bounds issue
When value < time_unit, the parameter of ilog2() will be zero and
the return value is -1. u64(-1) is too large for shift exponent
and then will trigger shift-out-of-bounds:
shift exponent 18446744073709551615 is too large for 32-bit type 'int'
Call Trace:
rapl_compute_time_window_core
rapl_write_data_raw
set_time_window
store_constraint_time_window_us
CVSS Score
7.1
EPSS Score
0.0
Published
2025-09-17
In the Linux kernel, the following vulnerability has been resolved:
fs: fix UAF/GPF bug in nilfs_mdt_destroy
In alloc_inode, inode_init_always() could return -ENOMEM if
security_inode_alloc() fails, which causes inode->i_private
uninitialized. Then nilfs_is_metadata_file_inode() returns
true and nilfs_free_inode() wrongly calls nilfs_mdt_destroy(),
which frees the uninitialized inode->i_private
and leads to crashes(e.g., UAF/GPF).
Fix this by moving security_inode_alloc just prior to
this_cpu_inc(nr_inodes)
CVSS Score
7.8
EPSS Score
0.0
Published
2025-09-17
In the Linux kernel, the following vulnerability has been resolved:
brcmfmac: return error when getting invalid max_flowrings from dongle
When firmware hit trap at initialization, host will read abnormal
max_flowrings number from dongle, and it will cause kernel panic when
doing iowrite to initialize dongle ring.
To detect this error at early stage, we directly return error when getting
invalid max_flowrings(>256).
CVSS Score
4.2
EPSS Score
0.0
Published
2025-09-17
In the Linux kernel, the following vulnerability has been resolved:
media: cx88: Fix a null-ptr-deref bug in buffer_prepare()
When the driver calls cx88_risc_buffer() to prepare the buffer, the
function call may fail, resulting in a empty buffer and null-ptr-deref
later in buffer_queue().
The following log can reveal it:
[ 41.822762] general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN PTI
[ 41.824488] KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
[ 41.828027] RIP: 0010:buffer_queue+0xc2/0x500
[ 41.836311] Call Trace:
[ 41.836945] __enqueue_in_driver+0x141/0x360
[ 41.837262] vb2_start_streaming+0x62/0x4a0
[ 41.838216] vb2_core_streamon+0x1da/0x2c0
[ 41.838516] __vb2_init_fileio+0x981/0xbc0
[ 41.839141] __vb2_perform_fileio+0xbf9/0x1120
[ 41.840072] vb2_fop_read+0x20e/0x400
[ 41.840346] v4l2_read+0x215/0x290
[ 41.840603] vfs_read+0x162/0x4c0
Fix this by checking the return value of cx88_risc_buffer()
[hverkuil: fix coding style issues]
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-17