Description
In the Linux kernel, the following vulnerability has been resolved: cachefiles: defer exposing anon_fd until after copy_to_user() succeeds After installing the anonymous fd, we can now see it in userland and close it. However, at this point we may not have gotten the reference count of the cache, but we will put it during colse fd, so this may cause a cache UAF. So grab the cache reference count before fd_install(). In addition, by kernel convention, fd is taken over by the user land after fd_install(), and the kernel should not call close_fd() after that, i.e., it should call fd_install() after everything is ready, thus fd_install() is called after copy_to_user() succeeds.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
Linux Linux
Default version status: unaffected
c8383054506c77b814489c09877b5db83fd4abf2 to < eac51d9daacd61dcc93333ff6a890cf3efc8c1c0affectedc8383054506c77b814489c09877b5db83fd4abf2 to < d2d3eb377a5d081bf2bed177d354a4f59b74da88affectedc8383054506c77b814489c09877b5db83fd4abf2 to < b9f58cdae6a364a3270fd6b6a46e0fd4f7f8ce32affectedc8383054506c77b814489c09877b5db83fd4abf2 to < 4b4391e77a6bf24cba2ef1590e113d9b73b11039affected
Linux Linux
Default version status: affected
5.19affected0 to < 5.19unaffected6.1.95 to ≤ 6.1.*unaffected6.6.35 to ≤ 6.6.*unaffected6.9.6 to ≤ 6.9.*unaffected6.10 to ≤ *unaffected
References
- https://git.kernel.org/stable/c/eac51d9daacd61dcc93333ff6a890cf3efc8c1c0 ↗
- https://git.kernel.org/stable/c/d2d3eb377a5d081bf2bed177d354a4f59b74da88 ↗
- https://git.kernel.org/stable/c/b9f58cdae6a364a3270fd6b6a46e0fd4f7f8ce32 ↗
- https://git.kernel.org/stable/c/4b4391e77a6bf24cba2ef1590e113d9b73b11039 ↗
- https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html ↗