7.0-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Nikola Z. Ivanov <redacted>

[ Upstream commit 35eaa6d8d6c2ee65e96f507add856e0eacf24591 ]

Syzbot reports a KMSAN uninit-value originating from
nsim_dev_trap_skb_build, with the allocation also
being performed in the same function.

Fix this by calling skb_put_zero instead of skb_put to
guarantee zero initialization of the whole IP header.

Closes: https://syzkaller.appspot.com/bug?extid=23d7fcd204e3837866ff
Fixes: da58f90f11f5 ("netdevsim: Add devlink-trap support")
Signed-off-by: Nikola Z. Ivanov <redacted>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260426201434.742030-1-zlatistiv@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/net/netdevsim/dev.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/netdevsim/dev.c b/drivers/net/netdevsim/dev.c
index e82de0fd31579..8f6d0a09e1761 100644
--- a/drivers/net/netdevsim/dev.c
+++ b/drivers/net/netdevsim/dev.c

@@ -829,7 +829,7 @@ static struct sk_buff *nsim_dev_trap_skb_build(void)
 	skb->protocol = htons(ETH_P_IP);
 
 	skb_set_network_header(skb, skb->len);
-	iph = skb_put(skb, sizeof(struct iphdr));
+	iph = skb_put_zero(skb, sizeof(struct iphdr));
 	iph->protocol = IPPROTO_UDP;
 	iph->saddr = in_aton("192.0.2.1");
 	iph->daddr = in_aton("198.51.100.1");

-- 
2.53.0