CVE-2025-38496

MEDIUM EPSS 3.7%
Published Jul 28, 202511mo ago · Modified Jun 17, 20261w ago
5.5 CVSS 3.1
Medium
Find Similar
Published Jul 28, 2025 11mo ago
Last Modified Jun 17, 2026 1w ago

Description

In the Linux kernel, the following vulnerability has been resolved: dm-bufio: fix sched in atomic context If "try_verify_in_tasklet" is set for dm-verity, DM_BUFIO_CLIENT_NO_SLEEP is enabled for dm-bufio. However, when bufio tries to evict buffers, there is a chance to trigger scheduling in spin_lock_bh, the following warning is hit: BUG: sleeping function called from invalid context at drivers/md/dm-bufio.c:2745 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 123, name: kworker/2:2 preempt_count: 201, expected: 0 RCU nest depth: 0, expected: 0 4 locks held by kworker/2:2/123: #0: ffff88800a2d1548 ((wq_completion)dm_bufio_cache){....}-{0:0}, at: process_one_work+0xe46/0x1970 #1: ffffc90000d97d20 ((work_completion)(&dm_bufio_replacement_work)){....}-{0:0}, at: process_one_work+0x763/0x1970 #2: ffffffff8555b528 (dm_bufio_clients_lock){....}-{3:3}, at: do_global_cleanup+0x1ce/0x710 #3: ffff88801d5820b8 (&c->spinlock){....}-{2:2}, at: do_global_cleanup+0x2a5/0x710 Preemption disabled at: [<0000000000000000>] 0x0 CPU: 2 UID: 0 PID: 123 Comm: kworker/2:2 Not tainted 6.16.0-rc3-g90548c634bd0 #305 PREEMPT(voluntary) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014 Workqueue: dm_bufio_cache do_global_cleanup Call Trace: <TASK> dump_stack_lvl+0x53/0x70 __might_resched+0x360/0x4e0 do_global_cleanup+0x2f5/0x710 process_one_work+0x7db/0x1970 worker_thread+0x518/0xea0 kthread+0x359/0x690 ret_from_fork+0xf3/0x1b0 ret_from_fork_asm+0x1a/0x30 </TASK> That can be reproduced by: veritysetup format --data-block-size=4096 --hash-block-size=4096 /dev/vda /dev/vdb SIZE=$(blockdev --getsz /dev/vda) dmsetup create myverity -r --table "0 $SIZE verity 1 /dev/vda /dev/vdb 4096 4096 <data_blocks> 1 sha256 <root_hash> <salt> 1 try_verify_in_tasklet" mount /dev/dm-0 /mnt -o ro echo 102400 > /sys/module/dm_bufio/parameters/max_cache_size_bytes [read files in /mnt]

CVSS Details

Base Score
5.5
Exploitability
1.8
Impact
3.6
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack Vector Local
Attack Complexity Low
Privileges Required Low
User Interaction None
Scope Unchanged
Confidentiality None
Integrity None
Availability High

Threat Intelligence

EPSS Exploit Probability
3.7% percentile
Exploit & Patch Status
No Known Exploit
Patch Available

Affected Products 9

VendorProductVersionRange
linuxlinux_kernel*≥6.4  –  <6.6.100
linuxlinux_kernel*≥6.7  –  <6.12.40
linuxlinux_kernel*≥6.13  –  <6.15.8
linuxlinux_kernel6.16any
linuxlinux_kernel6.16any
linuxlinux_kernel6.16any
linuxlinux_kernel6.16any
linuxlinux_kernel6.16any
linuxlinux_kernel6.16any

References 4

  • git.kernel.org https://git.kernel.org/stable/c/3edfdb1d4ef81320dae0caa40bc24baf8c1bbb86
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/469a39a33a9934af157299bf11c58f6e6cb53f85
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/68860d1ade385eef9fcdbf6552f061283091fdb8
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/b1bf1a782fdf5c482215c0c661b5da98b8e75773
    Patch

Remediation

  • git.kernel.org https://git.kernel.org/stable/c/3edfdb1d4ef81320dae0caa40bc24baf8c1bbb86
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/469a39a33a9934af157299bf11c58f6e6cb53f85
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/68860d1ade385eef9fcdbf6552f061283091fdb8
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/b1bf1a782fdf5c482215c0c661b5da98b8e75773
    Patch