CVE-2026-46322 PUBLISHED

tun: free page on build_skb failure in tun_xdp_one()

Assigner: Linux
Reserved: 13.05.2026 Published: 09.06.2026 Updated: 09.06.2026

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.

Product Status

Vendor Linux
Product Linux
Versions Default: unaffected
  • affected from 043d222f93ab8c76b56a3b315cd8692e35affb6c to d16e38fac09a47bfcf98c1ad65a1bb53f94540f5 (excl.)
  • affected from 043d222f93ab8c76b56a3b315cd8692e35affb6c to aa308e9dbb9acb17cacdbbce9e4504f69bac8385 (excl.)
  • affected from 043d222f93ab8c76b56a3b315cd8692e35affb6c to 4fefc6156a162a9f50035c12091a5e5130c82c6e (excl.)
  • affected from 043d222f93ab8c76b56a3b315cd8692e35affb6c to aa8963fdce667a42fb7f0bdd2909fadcab02f9a8 (excl.)
Vendor Linux
Product Linux
Versions Default: affected
  • Version 4.20 is affected
  • unaffected from 0 to 4.20 (excl.)
  • unaffected from 6.12.93 to 6.12.* (incl.)
  • unaffected from 6.18.35 to 6.18.* (incl.)
  • unaffected from 7.0.12 to 7.0.* (incl.)
  • unaffected from 7.1-rc6 to * (incl.)

References