diff --git a/include/linux/skmsg.h b/include/linux/skmsg.h index 0323a2b6c..49069b519 100644 --- a/include/linux/skmsg.h +++ b/include/linux/skmsg.h
[ ... ]
diff --git a/net/core/skmsg.c b/net/core/skmsg.c index d73e03f77..4390deaeb 100644 --- a/net/core/skmsg.c +++ b/net/core/skmsg.c
[ ... ]
@@ -820,8 +821,11 @@ static void __sk_psock_purge_ingress_msg(struct sk_psock *psock) if (!msg->skb) atomic_sub(msg->sg.size, &psock->sk->sk_rmem_alloc); sk_msg_free(psock->sk, msg);
sk_psock_inc_msg_size(psock, -msg->sg.size);- WARN_ON_ONCE(psock->ingress_size);
}
Can msg->sg.size be read after sk_msg_free()? Looking at sk_msg_free():
int sk_msg_free(struct sock *sk, struct sk_msg *msg) { return __sk_msg_free(sk, msg, msg->sg.start, true); }
And __sk_msg_free() at net/core/skmsg.c:207:
static int __sk_msg_free(struct sock *sk, struct sk_msg *msg, u32 i, bool charge) { ... while (msg->sg.size) { msg->sg.size -= sge->length; ... } consume_skb(msg->skb); sk_msg_init(msg); // <-- this zeros the entire msg structure return freed; }
And sk_msg_init() at include/linux/skmsg.h:193:
static inline void sk_msg_init(struct sk_msg *msg) { BUILD_BUG_ON(ARRAY_SIZE(msg->sg.data) - 1 != NR_MSG_FRAG_IDS); memset(msg, 0, sizeof(*msg)); // <-- zeros everything sg_init_marker(msg->sg.data, NR_MSG_FRAG_IDS); }
After sk_msg_free() completes, msg->sg.size is zero, so the line "sk_psock_inc_msg_size(psock, -msg->sg.size)" subtracts 0 instead of the actual message size. This means ingress_size will never be decremented during cleanup, and WARN_ON_ONCE(psock->ingress_size) will trigger whenever the ingress_msg queue contained messages.
The fix would be to save msg->sg.size before calling sk_msg_free():
u32 msg_size = msg->sg.size; if (!msg->skb) atomic_sub(msg_size, &psock->sk->sk_rmem_alloc); sk_msg_free(psock->sk, msg); sk_psock_inc_msg_size(psock, -msg_size); kfree(msg);
[ ... ]
--- AI reviewed your patch. Please fix the bug or email reply why it's not a bug. See: https://github.com/kernel-patches/vmtest/blob/master/ci/claude/README.md
CI run summary: https://github.com/kernel-patches/bpf/actions/runs/19558612316