CVE-2024-38580 — epoll: be better about file lifetimes
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 wi…
Published: 2024-06-19 · CVSS: 7.8 · CVSS 3.1
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.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7