CVE-2026-80841EPSS p6.0%
CVE-2026-80841CVE-2026-80841
Description
In the Linux kernel, the following vulnerability has been resolved:
net/packet: defer vmalloc TX_RING free until skbs finish
AF_PACKET TX_RING skbs keep a raw pointer to their ring frame. The skb
page references preserve page-backed ring blocks after pg_vec is freed,
but they do not preserve a vmalloc mapping.
tpacket_destruct_skb() currently drops the pending reference before
writing the timestamp and TP_STATUS_AVAILABLE to the frame. Move the
decrement after those stores. The smp_wmb() in __packet_set_status()
orders the frame stores before the decrement.
Also recheck pending TX frames under pg_vec_lock before non-closing
ring replacement, so a racing send cannot add a pending skb between
the initial check and the ring swap.
Ring allocation can produce a mixture of page-backed and vmalloc-backed
blocks. Allocate deferred-work storage during TX ring setup when the
first vmalloc-backed block is encountered, and keep its pointer in the
pg_vec allocation header. If allocation fails,
Scoring
| EPSS | 0.17% probability of exploitation · percentile 6.0% · 2026-10-05T12:00:23Z |
| Last modified | 2026-10-03 |