cbcvebase.
CVE-2025-21634
published 2025-01-19

CVE-2025-21634: In the Linux kernel, the following vulnerability has been resolved: cgroup/cpuset: remove kernfs active break A warning was found: WARNING: CPU: 10 PID…

PriorityP419medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.14%
3.7th percentile
In the Linux kernel, the following vulnerability has been resolved: cgroup/cpuset: remove kernfs active break A warning was found: WARNING: CPU: 10 PID: 3486953 at fs/kernfs/file.c:828 CPU: 10 PID: 3486953 Comm: rmdir Kdump: loaded Tainted: G RIP: 0010:kernfs_should_drain_open_files+0x1a1/0x1b0 RSP: 0018:ffff8881107ef9e0 EFLAGS: 00010202 RAX: 0000000080000002 RBX: ffff888154738c00 RCX: dffffc0000000000 RDX: 0000000000000007 RSI: 0000000000000004 RDI: ffff888154738c04 RBP: ffff888154738c04 R08: ffffffffaf27fa15 R09: ffffed102a8e7180 R10: ffff888154738c07 R11: 0000000000000000 R12: ffff888154738c08 R13: ffff888750f8c000 R14: ffff888750f8c0e8 R15: ffff888154738ca0 FS: 00007f84cd0be740(0000) GS:ffff8887ddc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555f9fbe00c8 CR3: 0000000153eec001 CR4: 0000000000370ee0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: kernfs_drain+0x15e/0x2f0 __kernfs_remove+0x165/0x300 kernfs_remove_by_name_ns+0x7b/0xc0 cgroup_rm_file+0x154/0x1c0 cgroup_addrm_files+0x1c2/0x1f0 css_clear_dir+0x77/0x110 kill_css+0x4c/0x1b0 cgroup_destroy_locked+0x194/0x380 cgroup_rmdir+0x2a/0x140 It can be explained by: rmdir echo 1 > cpuset.cpus kernfs_fop_write_iter // active=0 cgroup_rm_file kernfs_remove_by_name_ns kernfs_get_active // active=1 __kernfs_remove // active=0x80000002 kernfs_drain cpuset_write_resmask wait_event //waiting (active == 0x80000001) kernfs_break_active_protection // active = 0x80000001 // continue kernfs_unbreak_active_protection // active = 0x80000002 ... kernfs_should_drain_open_files // warning occurs kernfs_put_active This warning is caused by 'kernfs_break_active_protection' when it is writing to cpuset.cpus, and the cgroup is removed concurrently. The commit 3a5a6d0c2b03 ("cpuset: don't nest cgroup_mutex inside get_online_cpus()") made cpuset_hotplug_workfn asynchronous, This change invol

Affected

9 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 6.12.10-1 (forky)linux 6.12.10-1 (forky)
linuxlinux
linuxlinux>= 76bb5ab8f6e3e7bebdcefec4146ff305e7d0b465 < 11cb1d643a74665a4e14749414f48f82cbc15c6411cb1d643a74665a4e14749414f48f82cbc15c64
linuxlinux>= 76bb5ab8f6e3e7bebdcefec4146ff305e7d0b465 < 3cb97a927fffe443e1e7e8eddbfebfdb062e86ed3cb97a927fffe443e1e7e8eddbfebfdb062e86ed
linuxlinux_kernel
linuxlinux_kernel>= 0 < 6.12.10-16.12.10-1
linuxlinux_kernel>= 0 < 6.12.10-16.12.10-1
linuxlinux_kernel>= 0 < 6.8.0-60.636.8.0-60.63
linuxlinux_kernel>= 3.16 < 6.12.106.12.10

CVSS provenance

nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv7.8HIGH
vendor_ubuntu7.8HIGH
vendor_debian5.5MEDIUM
vendor_redhat5.5MEDIUM
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