CVE-2024-41048

A zero-length socket buffer (skb) can be placed on the sk_msg ingress queue. This occurs when a TCP FIN is processed, such as when shutdown(p1, SHUT_WR) is called. Because the skb has zero length, no memory page is associated with its scatter-gather entry.

Later, sk_msg_recvmsg() processes this empty entry and obtains a NULL page pointer through sg_page(). The NULL pointer is then passed through copy_page_to_iter() to kmap_local_page()/page_address(). On architectures such as LoongArch, this results in a kernel panic. The issue was less visible on x86 because of architecture-specific page_address() behavior.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.