In the Linux kernel, the following vulnerability has been resolved: smb: client: fix reparse buffer bounds in cifs_query_reparse_point() I

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

smb: client: fix reparse buffer bounds in cifs_query_reparse_point()

In cifs_query_reparse_point(), the start >= end check before casting to
struct reparse_data_buffer * only ensures the start pointer is within the
response. It fails to verify that there is enough space remaining for the
fixed 8-byte header of the structure.

If a server provides a DataOffset that leaves less than 8 bytes remaining,
the check passes, but subsequent reads of ReparseTag and ReparseDataLength
will occur out-of-bounds.

Fix this by ensuring the remaining space is at least the size of the
reparse_data_buffer structure before accessing its fields.