In the Linux kernel, the following vulnerability has been resolved:

sysctl: Fix out of bounds access for empty sysctl registers

When registering tables to the sysctl subsystem there is a check to see
if header is a permanently empty directory (used for mounts). This check
evaluates the first element of the ctl_table. This results in an out of
bounds evaluation when registering empty directories.

The function register_sysctl_mount_point now passes a ctl_table of size
1 instead of size 0. It now relies solely on the type to identify
a permanently empty register.

Make sure that the ctl_table has at least one element before testing for
permanent emptiness.

References

• https://nvd.nist.gov/vuln/detail/CVE-2023-52596
• https://git.kernel.org/stable/c/15893975e9e382f8294ea8d926f08dc2d8d39ede
• https://git.kernel.org/stable/c/2ae7081bc10123b187e36a4f3a8e53768de31489
• https://git.kernel.org/stable/c/315552310c7de92baea4e570967066569937a843