Affected: Linux, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 10.0 Extended Update Support, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support, Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On, Red Hat Enterprise Linux 8.8 Telecommunications Update Service, Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions, Red Hat Enterprise Linux 9, Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions and 15 more

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

fs/smb/client: fix out-of-bounds read in cifs_sanitize_prepath

When cifs_sanitize_prepath is called with an empty string or a string containing only delimiters (e.g., "/"), the current logic attempts to check *(cursor2 - 1) before cursor2 has advanced. This results in an out-of-bounds read.

This patch adds an early exit check after stripping prepended delimiters. If no path content remains, the function returns NULL.

The bug was identified via manual audit and verified using a standalone test case compiled with AddressSanitizer, which triggered a SEGV on affected inputs.