From: Artem Chernyshev <artem.chernyshev@xxxxxxxxxxx> [ Upstream commit 3d8fdcbf1f42e2bb9ae8b8c0b6f202278c788a22 ] Return NULL if we got unexpected value from skb_trim_rcsum() in ksz_common_rcv() Found by Linux Verification Center (linuxtesting.org) with SVACE. Fixes: bafe9ba7d908 ("net: dsa: ksz: Factor out common tag code") Signed-off-by: Artem Chernyshev <artem.chernyshev@xxxxxxxxxxx> Reviewed-by: Vladimir Oltean <olteanv@xxxxxxxxx> Reviewed-by: Florian Fainelli <f.fainelli@xxxxxxxxx> Link: https://lore.kernel.org/r/20221201140032.26746-1-artem.chernyshev@xxxxxxxxxxx Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- net/dsa/tag_ksz.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/dsa/tag_ksz.c b/net/dsa/tag_ksz.c index 73605bcbb385..7354c5db3a14 100644 --- a/net/dsa/tag_ksz.c +++ b/net/dsa/tag_ksz.c @@ -62,7 +62,8 @@ static struct sk_buff *ksz_common_rcv(struct sk_buff *skb, if (!skb->dev) return NULL; - pskb_trim_rcsum(skb, skb->len - len); + if (pskb_trim_rcsum(skb, skb->len - len)) + return NULL; skb->offload_fwd_mark = true; -- 2.35.1