cbcvebase.
CVE-2023-52707
published 2024-05-21

CVE-2023-52707: In the Linux kernel, the following vulnerability has been resolved: sched/psi: Fix use-after-free in ep_remove_wait_queue() If a non-root cgroup gets removed…

PriorityP339high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.26%
17.9th percentile
In the Linux kernel, the following vulnerability has been resolved: sched/psi: Fix use-after-free in ep_remove_wait_queue() If a non-root cgroup gets removed when there is a thread that registered trigger and is polling on a pressure file within the cgroup, the polling waitqueue gets freed in the following path: do_rmdir cgroup_rmdir kernfs_drain_open_files cgroup_file_release cgroup_pressure_release psi_trigger_destroy However, the polling thread still has a reference to the pressure file and will access the freed waitqueue when the file is closed or upon exit: fput ep_eventpoll_release ep_free ep_remove_wait_queue remove_wait_queue This results in use-after-free as pasted below. The fundamental problem here is that cgroup_file_release() (and consequently waitqueue's lifetime) is not tied to the file's real lifetime. Using wake_up_pollfree() here might be less than ideal, but it is in line with the comment at commit 42288cb44c4b ("wait: add wake_up_pollfree()") since the waitqueue's lifetime is not tied to file's one and can be considered as another special case. While this would be fixable by somehow making cgroup_file_release() be tied to the fput(), it would require sizable refactoring at cgroups or higher layer which might be more justifiable if we identify more cases like this. BUG: KASAN: use-after-free in _raw_spin_lock_irqsave+0x60/0xc0 Write of size 4 at addr ffff88810e625328 by task a.out/4404 CPU: 19 PID: 4404 Comm: a.out Not tainted 6.2.0-rc6 #38 Hardware name: Amazon EC2 c5a.8xlarge/, BIOS 1.0 10/16/2017 Call Trace: dump_stack_lvl+0x73/0xa0 print_report+0x16c/0x4e0 kasan_report+0xc3/0xf0 kasan_check_range+0x2d2/0x310 _raw_spin_lock_irqsave+0x60/0xc0 remove_wait_queue+0x1a/0xa0 ep_free+0x12c/0x170 ep_eventpoll_release+0x26/0x30 __fput+0x202/0x400 task_work_run+0x11d/0x170 do_exit+0x495/0x1130 do_group_exit+0x100/0x100 get_signal+0xd67/0xde0 arch_do_signal_or_restart+0x2a/0x2b0 exit_to_user_mode_prepare+0x94/0x100 syscall_exit_to_user_mode+0x20

Affected

16 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 6.1.15-1 (bookworm)linux 6.1.15-1 (bookworm)
linuxlinux——
linuxlinux>= 0e94682b73bfa6c44c98af7a26771c9c08c055d5 < 7caeb5457bd01ccba0df1d6f4872f20d28e50b387caeb5457bd01ccba0df1d6f4872f20d28e50b38
linuxlinux>= 0e94682b73bfa6c44c98af7a26771c9c08c055d5 < ec9c7aa08819f976b2492fa63c41b5712d2924b5ec9c7aa08819f976b2492fa63c41b5712d2924b5
linuxlinux>= 0e94682b73bfa6c44c98af7a26771c9c08c055d5 < cca2b3feb70170ef6f0fbc4b4d91eea235a2b73acca2b3feb70170ef6f0fbc4b4d91eea235a2b73a
linuxlinux>= 0e94682b73bfa6c44c98af7a26771c9c08c055d5 < c6879a4dcefe92d870ab68cabaa9caeda4f2af5ac6879a4dcefe92d870ab68cabaa9caeda4f2af5a
linuxlinux>= 0e94682b73bfa6c44c98af7a26771c9c08c055d5 < c2dbe32d5db5c4ead121cf86dabd5ab691fb47fec2dbe32d5db5c4ead121cf86dabd5ab691fb47fe
linuxlinux_kernel——
linuxlinux_kernel>= 0 < 5.10.178-15.10.178-1
linuxlinux_kernel>= 0 < 6.1.15-16.1.15-1
linuxlinux_kernel>= 0 < 6.1.15-16.1.15-1
linuxlinux_kernel>= 0 < 6.1.15-16.1.15-1
linuxlinux_kernel>= 5.11 < 5.15.955.15.95
linuxlinux_kernel>= 5.16 < 6.1.136.1.13
linuxlinux_kernel>= 5.2 < 5.4.2325.4.232
linuxlinux_kernel>= 5.5 < 5.10.1695.10.169

CVSS provenance

nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
osv7.8HIGH
vendor_debian7.8HIGH
vendor_redhat7.8HIGH
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