Commit 9e8d1013 authored by Oleksij Rempel's avatar Oleksij Rempel Committed by Paolo Abeni
Browse files

net: selftests: initialize TCP header and skb payload with zero 



Zero-initialize TCP header via memset() to avoid garbage values that
may affect checksum or behavior during test transmission.

Also zero-fill allocated payload and padding regions using memset()
after skb_put(), ensuring deterministic content for all outgoing
test packets.

Fixes: 3e1e58d6 ("net: add generic selftest support")
Signed-off-by: default avatarOleksij Rempel <o.rempel@pengutronix.de>
Cc: stable@vger.kernel.org
Reviewed-by: default avatarSimon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250416160125.2914724-1-o.rempel@pengutronix.de


Signed-off-by: default avatarPaolo Abeni <pabeni@redhat.com>
parent 30a41ed3

net/core/selftests.c

+13 −5
Original line number Diff line number Diff line
@@ -100,10 +100,10 @@ static struct sk_buff *net_test_get_skb(struct net_device *ndev, 
	ehdr->h_proto = htons(ETH_P_IP);



	if (attr->tcp) {

		memset(thdr, 0, sizeof(*thdr));

		thdr->source = htons(attr->sport);

		thdr->dest = htons(attr->dport);

		thdr->doff = sizeof(struct tcphdr) / 4;

		thdr->check = 0;

	} else {

		uhdr->source = htons(attr->sport);

		uhdr->dest = htons(attr->dport);
@@ -144,10 +144,18 @@ static struct sk_buff *net_test_get_skb(struct net_device *ndev, 
	attr->id = net_test_next_id;

	shdr->id = net_test_next_id++;



	if (attr->size)

		skb_put(skb, attr->size);

	if (attr->max_size && attr->max_size > skb->len)

		skb_put(skb, attr->max_size - skb->len);

	if (attr->size) {

		void *payload = skb_put(skb, attr->size);



		memset(payload, 0, attr->size);

	}



	if (attr->max_size && attr->max_size > skb->len) {

		size_t pad_len = attr->max_size - skb->len;

		void *pad = skb_put(skb, pad_len);



		memset(pad, 0, pad_len);

	}



	skb->csum = 0;

	skb->ip_summed = CHECKSUM_PARTIAL;