CVE-2026-53238

Description

In the Linux kernel, the following vulnerability has been resolved: netlabel: validate unlabeled address and mask attribute lengths netlbl_unlabel_addrinfo_get() used the address attribute length to determine whether the attribute data could be read as an IPv4 or IPv6 address, but did not independently validate the corresponding mask attribute length. A crafted Generic Netlink request could therefore provide a valid IPv4/IPv6 address attribute with a shorter mask attribute, which would later be read as a full struct in_addr or struct in6_addr. NLA_BINARY policy lengths are maximum lengths by default, so use NLA_POLICY_EXACT_LEN() for the unlabeled IPv4/IPv6 address and mask attributes. This rejects short attributes during policy validation and also exposes the exact length requirements through policy introspection.

References

• https://git.kernel.org/stable/c/07a18f5c90dd3d586b73242f5a5bbf0a72f2fdc6
• https://git.kernel.org/stable/c/0c4bb32ad7fdc2dc6a8050f41eb04d4bda56b6c8
• https://git.kernel.org/stable/c/672f0f3b8f875ffe6525a37847eafa7648c4c0c6
• https://git.kernel.org/stable/c/71c52da13c3737493b42d20d9f33de34e03b3156
• https://git.kernel.org/stable/c/95bda3eac0b1454c2cee98d58d9ba6dd8391e843