Red Hat: CVE-2024-38580: kernel: epoll: be better about file lifetimes (Multiple Advisories)

Red Hat: CVE-2024-38580: kernel: epoll: be better about file lifetimes (Multiple Advisories)

Severity

2

CVSS

(AV:L/AC:L/Au:S/C:N/I:N/A:P)

Published

06/19/2024

Created

12/06/2024

Added

12/05/2024

Modified

12/05/2024

Description

In the Linux kernel, the following vulnerability has been resolved: epoll: be better about file lifetimes epoll can call out to vfs_poll() with a file pointer that may race with the last 'fput()'. That would make f_count go down to zero, and while the ep->mtx locking means that the resulting file pointer tear-down will be blocked until the poll returns, it means that f_count is already dead, and any use of it won't actually get a reference to the file any more: it's dead regardless. Make sure we have a valid ref on the file pointer before we call down to vfs_poll() from the epoll routines.

Solution(s)

• redhat-upgrade-kernel
• redhat-upgrade-kernel-rt

References

• CVE-2024-38580
• RHSA-2024:4928