Description

In the Linux kernel, the following vulnerability has been resolved: tun: free page on build_skb failure in tun_xdp_one() When build_skb() fails in tun_xdp_one(), the function sets ret to -ENOMEM and jumps to the out label, which returns without freeing the page that vhost_net_build_xdp() allocated for the frame. As with the short-frame rejection path, tun_sendmsg() discards the per-buffer error and still returns total_len, so vhost_tx_batch() takes the success path and never frees the page. Each build_skb() failure in a batch leaks one page-frag chunk. Free the page before taking the error path, matching the put_page() the other error exits of tun_xdp_one() already perform.

References 8

• git.kernel.org https://git.kernel.org/stable/c/2638a9c1521905bb5c5d1e95c8fbc09f79148ed7
• git.kernel.org https://git.kernel.org/stable/c/26fe549b5192536b6c1c68a2dfdc8c0dcf9fa4a9
• git.kernel.org https://git.kernel.org/stable/c/4fefc6156a162a9f50035c12091a5e5130c82c6e
• git.kernel.org https://git.kernel.org/stable/c/60d9c0d6cdde5420d6483c921b16fe5465eb5238
• git.kernel.org https://git.kernel.org/stable/c/793385c154771603b8671dd8338927221e9d8d78
• git.kernel.org https://git.kernel.org/stable/c/aa308e9dbb9acb17cacdbbce9e4504f69bac8385
• git.kernel.org https://git.kernel.org/stable/c/aa8963fdce667a42fb7f0bdd2909fadcab02f9a8
• git.kernel.org https://git.kernel.org/stable/c/d16e38fac09a47bfcf98c1ad65a1bb53f94540f5

Remediation