CVE - CVE-2024-43869

CVE-ID
CVE-2024-43869	Learn more at National Vulnerability Database (NVD) • CVSS Severity Rating • Fix Information • Vulnerable Software Versions • SCAP Mappings • CPE Information
Description
In the Linux kernel, the following vulnerability has been resolved: perf: Fix event leak upon exec and file release The perf pending task work is never waited upon the matching event release. In the case of a child event, released via free_event() directly, this can potentially result in a leaked event, such as in the following scenario that doesn't even require a weak IRQ work implementation to trigger: schedule() prepare_task_switch() =======> <NMI> perf_event_overflow() event->pending_sigtrap = ... irq_work_queue(&event->pending_irq) <======= </NMI> perf_event_task_sched_out() event_sched_out() event->pending_sigtrap = 0; atomic_long_inc_not_zero(&event->refcount) task_work_add(&event->pending_task) finish_lock_switch() =======> <IRQ> perf_pending_irq() //do nothing, rely on pending task work <======= </IRQ> begin_new_exec() perf_event_exit_task() perf_event_exit_event() // If is child event free_event() WARN(atomic_long_cmpxchg(&event->refcount, 1, 0) != 1) // event is leaked Similar scenarios can also happen with perf_event_remove_on_exec() or simply against concurrent perf_event_release(). Fix this with synchonizing against the possibly remaining pending task work while freeing the event, just like is done with remaining pending IRQ work. This means that the pending task callback neither need nor should hold a reference to the event, preventing it from ever beeing freed.
References
Note: References are provided for the convenience of the reader to help distinguish between vulnerabilities. The list is not intended to be complete.
MISC:https://git.kernel.org/stable/c/104e258a004037bc7dba9f6085c71dad6af57ad4 URL:https://git.kernel.org/stable/c/104e258a004037bc7dba9f6085c71dad6af57ad4 MISC:https://git.kernel.org/stable/c/3a5465418f5fd970e86a86c7f4075be262682840 URL:https://git.kernel.org/stable/c/3a5465418f5fd970e86a86c7f4075be262682840 MISC:https://git.kernel.org/stable/c/9ad46f1fef421d43cdab3a7d1744b2f43b54dae0 URL:https://git.kernel.org/stable/c/9ad46f1fef421d43cdab3a7d1744b2f43b54dae0 MISC:https://git.kernel.org/stable/c/ed2c202dac55423a52d7e2290f2888bf08b8ee99 URL:https://git.kernel.org/stable/c/ed2c202dac55423a52d7e2290f2888bf08b8ee99 MISC:https://git.kernel.org/stable/c/f34d8307a73a18de5320fcc6f40403146d061891 URL:https://git.kernel.org/stable/c/f34d8307a73a18de5320fcc6f40403146d061891
Assigning CNA
kernel.org
Date Record Created
20240817	Disclaimer: The record creation date may reflect when the CVE ID was allocated or reserved, and does not necessarily indicate when this vulnerability was discovered, shared with the affected vendor, publicly disclosed, or updated in CVE.
Phase (Legacy)
Assigned (20240817)
Votes (Legacy)

Comments (Legacy)

Proposed (Legacy)
N/A
This is an record on the CVE List, which provides common identifiers for publicly known cybersecurity vulnerabilities.
Search CVE Using Keywords: You can also search by reference using the CVE Reference Maps.
For More Information: CVE Request Web Form (select "Other" from dropdown)