cbcvebase.
CVE-2024-43870
published 2024-08-21

CVE-2024-43870: In the Linux kernel, the following vulnerability has been resolved: perf: Fix event leak upon exit When a task is scheduled out, pending sigtrap deliveries are…

PriorityP417medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.21%
11.5th percentile
In the Linux kernel, the following vulnerability has been resolved: perf: Fix event leak upon exit When a task is scheduled out, pending sigtrap deliveries are deferred to the target task upon resume to userspace via task_work. However failures while adding an event's callback to the task_work engine are ignored. And since the last call for events exit happen after task work is eventually closed, there is a small window during which pending sigtrap can be queued though ignored, leaking the event refcount addition such as in the following scenario: TASK A do_exit() exit_task_work(tsk); perf_event_overflow() event->pending_sigtrap = pending_id; irq_work_queue(&event->pending_irq); =========> PREEMPTION: TASK A -> TASK B event_sched_out() event->pending_sigtrap = 0; atomic_long_inc_not_zero(&event->refcount) // FAILS: task work has exited task_work_add(&event->pending_task) [...] perf_pending_irq() // early return: event->oncpu = -1 [...] =========> TASK B -> TASK A perf_event_exit_task(tsk) perf_event_exit_event() free_event() WARN(atomic_long_cmpxchg(&event->refcount, 1, 0) != 1) // leak event due to unexpected refcount == 2 As a result the event is never released while the task exits. Fix this with appropriate task_work_add()'s error handling.

Affected

22 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 6.1.106-1 (bookworm)linux 6.1.106-1 (bookworm)
debianlinux-6.1< linux 6.1.106-1 (bookworm)linux 6.1.106-1 (bookworm)
linuxlinux
linuxlinux
linuxlinux>= 5.15.84 < 5.15.1655.15.165
linuxlinux>= 517e6a301f34613bff24a8e35b5455884f2d83d8 < 70882d7fa74f0731492a0d493e8515a4f713183170882d7fa74f0731492a0d493e8515a4f7131831
linuxlinux>= 517e6a301f34613bff24a8e35b5455884f2d83d8 < 05d3fd599594abf79aad4484bccb2b26e1cb0b5105d3fd599594abf79aad4484bccb2b26e1cb0b51
linuxlinux>= 517e6a301f34613bff24a8e35b5455884f2d83d8 < 3d7a63352a93bdb8a1cdf29606bf617d3ac1c22a3d7a63352a93bdb8a1cdf29606bf617d3ac1c22a
linuxlinux>= 517e6a301f34613bff24a8e35b5455884f2d83d8 < 2fd5ad3f310de22836cdacae919dd99d758a1f1b2fd5ad3f310de22836cdacae919dd99d758a1f1b
linuxlinux>= 6.0.14 < 6.16.1
linuxlinux>= 8bffa95ac19ff27c8261904f89d36c7fcf215d59 < 67fad724f1b568b356c1065d50df46e6b30eb2f767fad724f1b568b356c1065d50df46e6b30eb2f7
linuxlinux_kernel
linuxlinux_kernel>= 0 < 6.1.106-16.1.106-1
linuxlinux_kernel>= 0 < 6.10.3-16.10.3-1
linuxlinux_kernel>= 0 < 6.10.3-16.10.3-1
linuxlinux_kernel>= 0 < 5.15.0-125.1355.15.0-125.135
linuxlinux_kernel>= 0 < 6.8.0-50.516.8.0-50.51
linuxlinux_kernel>= 5.15.84 < 5.15.1655.15.165
linuxlinux_kernel>= 6.0.14 < 6.16.1
linuxlinux_kernel>= 6.1.1 < 6.1.1036.1.103
linuxlinux_kernel>= 6.2 < 6.6.446.6.44
linuxlinux_kernel>= 6.7 < 6.10.36.10.3

CVSS provenance

nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv8.8HIGH
vendor_ubuntu8.8HIGH
vendor_debian5.5MEDIUM
vendor_redhat5.5MEDIUM
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