5.15-stable review patch. If anyone has any objections, please let me know.
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From: Oleksij Rempel o.rempel@pengutronix.de
commit 9e8d1013b0c38910cbc9e60de74dbe883878469d upstream.
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: 3e1e58d64c3d ("net: add generic selftest support") Signed-off-by: Oleksij Rempel o.rempel@pengutronix.de Cc: stable@vger.kernel.org Reviewed-by: Simon Horman horms@kernel.org Link: https://patch.msgid.link/20250416160125.2914724-1-o.rempel@pengutronix.de Signed-off-by: Paolo Abeni pabeni@redhat.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/core/selftests.c | 18 +++++++++++++----- 1 file changed, 13 insertions(+), 5 deletions(-)
--- a/net/core/selftests.c +++ b/net/core/selftests.c @@ -100,10 +100,10 @@ static struct sk_buff *net_test_get_skb( 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( 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;