CVE-2026-31502

Description

In the Linux kernel, the following vulnerability has been resolved: team: fix header_ops type confusion with non-Ethernet ports Similar to commit 950803f72547 ("bonding: fix type confusion in bond_setup_by_slave()") team has the same class of header_ops type confusion. For non-Ethernet ports, team_setup_by_port() copies port_dev->header_ops directly. When the team device later calls dev_hard_header() or dev_parse_header(), these callbacks can run with the team net_device instead of the real lower device, so netdev_priv(dev) is interpreted as the wrong private type and can crash. The syzbot report shows a crash in bond_header_create(), but the root cause is in team: the topology is gre -> bond -> team, and team calls the inherited header_ops with its own net_device instead of the lower device, so bond_header_create() receives a team device and interprets netdev_priv() as bonding private data, causing a type confusion crash. Fix this by introducing team header_ops wrappers for create/parse, selecting a team port under RCU, and calling the lower device callbacks with port->dev, so each callback always sees the correct net_device context. Also pass the selected lower device to the lower parse callback, so recursion is bounded in stacked non-Ethernet topologies and parse callbacks always run with the correct device context.

Affected products

Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.

References

• https://git.kernel.org/stable/c/c6e255b0ce30cdea37e34d6d87e2212eb8c7f7a4 ↗
• https://git.kernel.org/stable/c/420e5aad7ba89e8f79e2dc8327b0c0c24c1c1d53 ↗
• https://git.kernel.org/stable/c/6d3161fa3eee64d46b766fb0db33ec7f300ef52d ↗
• https://git.kernel.org/stable/c/0a7468ed49a6b65d34abcc6eb60e15f7f6d34da0 ↗
• https://git.kernel.org/stable/c/20491d384d973a63fbdaf7a71e38d69b0659ea55 ↗
• https://git.kernel.org/stable/c/425000dbf17373a4ab8be9428f5dc055ef870a56 ↗