جزئیات آسیب‌پذیری

In the Linux kernel, the following vulnerability has been resolved: nfc: llcp: read llcp_sock->local under the socket lock in getsockopt nfc_llcp_getsockopt() read llcp_sock->local before lock_sock(sk) and then dereferenced the cached pointer inside the locked region. llcp_sock_bind() assigns and clears llcp_sock->local under the same socket lock, dropping the last reference on its error path. A getsockopt() racing an in-flight bind() can observe the pointer, block on lock_sock(), and then dereference a freed nfc_llcp_local once bind() has unwound. Move the llcp_sock->local read and the NULL check inside the lock_sock(sk) region so bind() cannot mutate or free the pointer between the load and the use.

• https://git.kernel.org/stable/c/56fd158fef20268f48db6cdfe5d722e930134eda
• https://git.kernel.org/stable/c/8ba8cec0586727cc135ca4827921fc7b52946d71
• https://git.kernel.org/stable/c/ed5240bab3468988077fe8bf29b935eaecc9ff89
• https://git.kernel.org/stable/c/fe65727a4a21b11c18eebae1338482767a897b76
• https://git.kernel.org/stable/c/2d8ac24565be85bf56580b87bf1b874d35625eb5
• https://git.kernel.org/stable/c/156e65bd29307f5053835bff60bc1ba342fa010f
• https://git.kernel.org/stable/c/d1b73962675cdc5a58e2707e25b548d8b495fde0
• https://git.kernel.org/stable/c/36812527052c5bfb1ec6c1e292d67a5bf76b750f