CVE-2026-43011

In the Linux kernel, the following vulnerability has been resolved:

net/x25: Fix potential double free of skb

When alloc_skb fails in x25_queue_rx_frame it calls kfree_skb(skb) at

line 48 and returns 1 (error).

This error propagates back through the call chain:

x25_queue_rx_frame returns 1

|

v

x25_state3_machine receives the return value 1 and takes the else

branch at line 278, setting queued=0 and returning 0

|

v

x25_process_rx_frame returns queued=0

|

v

x25_backlog_rcv at line 452 sees queued=0 and calls kfree_skb(skb)

again

This would free the same skb twice. Looking at x25_backlog_rcv:

net/x25/x25_in.c:x25_backlog_rcv() {

...

queued = x25_process_rx_frame(sk, skb);

...

if (!queued)

kfree_skb(skb);

}