Description

In the Linux kernel, the following vulnerability has been resolved: ipv6/sit: use DEV_STATS_INC() to avoid data-races syzbot/KCSAN reported that multiple cpus are updating dev->stats.tx_error concurrently. This is because sit tunnels are NETIF_F_LLTX, meaning their ndo_start_xmit() is not protected by a spinlock. While original KCSAN report was about tx path, rx path has the same issue.

References 4

• git.kernel.org https://git.kernel.org/stable/c/207501a986831174df09a36a8cb62a28f92f0dc8
• git.kernel.org https://git.kernel.org/stable/c/222cc04356984f3f98acfa756a69d4bed7c501ac
• git.kernel.org https://git.kernel.org/stable/c/4eed93bb3e57b8cc78d17166a14e40a73276015a
• git.kernel.org https://git.kernel.org/stable/c/cb34b7cf17ecf33499c9298943f85af247abc1e9

Remediation