net: strparser: fix skb_head leak in strp_abort_strp()

From: Luxiao Xu <[email protected]>

When the stream parser is aborted, for example after a message assembly timeout, it can still hold a reference to a partially assembled message in strp->skb_head.

That skb is not released in strp_abort_strp(), which leaks the partially assembled message and can be triggered repeatedly to exhaust memory.

Fix this by freeing strp->skb_head and resetting the parser state in the abort path. Leave strp_stop() unchanged so final cleanup still happens in strp_done() after the work and timer have been synchronized.

---
 net/strparser/strparser.c | 8 ++++++++
 1 file changed, 8 insertions(+)

index fe0e76fdd1f1..a23f4b4dfc67 100644
@@ -45,6 +45,14 @@ static void strp_abort_strp(struct strparser *strp, int err)
 
 	strp->stopped = 1;
 
+	if (strp->skb_head) {
+		kfree_skb(strp->skb_head);
+		strp->skb_head = NULL;
+	}
+
+	strp->skb_nextp = NULL;
+	strp->need_bytes = 0;
+
 	if (strp->sk) {
 		struct sock *sk = strp->sk;
 

2.43.0