From: Luka Gejak Ensure the entire TLV header is linearized before access by adding sizeof(struct hsr_sup_tlv) to the pskb_may_pull() calls. Without this, a truncated frame could cause an out-of-bounds access. Assisted-by: Gemini:Gemini-3.1-flash Fixes: eafaa88b3eb7 ("net: hsr: Add support for redbox supervision frames") Signed-off-by: Luka Gejak --- NOTE: This patch was previously part of a net-next series and was seperated as requested by Jakub Kicinski. Link to the old series is [1]. [1]:https://lore.kernel.org/netdev/20260513182657.20346-1-luka.gejak@linux.dev/ net/hsr/hsr_forward.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/hsr/hsr_forward.c b/net/hsr/hsr_forward.c index 0aca859c88cb..f669a226d728 100644 --- a/net/hsr/hsr_forward.c +++ b/net/hsr/hsr_forward.c @@ -84,7 +84,7 @@ static bool is_supervision_frame(struct hsr_priv *hsr, struct sk_buff *skb) /* Get next tlv */ total_length += hsr_sup_tag->tlv.HSR_TLV_length; - if (!pskb_may_pull(skb, total_length)) + if (!pskb_may_pull(skb, total_length + sizeof(struct hsr_sup_tlv))) return false; skb_pull(skb, total_length); hsr_sup_tlv = (struct hsr_sup_tlv *)skb->data; @@ -100,7 +100,7 @@ static bool is_supervision_frame(struct hsr_priv *hsr, struct sk_buff *skb) /* make sure another tlv follows */ total_length += sizeof(struct hsr_sup_tlv) + hsr_sup_tlv->HSR_TLV_length; - if (!pskb_may_pull(skb, total_length)) + if (!pskb_may_pull(skb, total_length + sizeof(struct hsr_sup_tlv))) return false; /* get next tlv */ -- 2.54.0