hsr: Prevent use after free in prp_create_tagged_frame()

The prp_fill_rct() function can fail.  In that situation, it frees the
skb and returns NULL.  Meanwhile on the success path, it returns the
original skb.  So it's straight forward to fix bug by using the returned
value.

Fixes: 451d8123f8 ("net: prp: add packet handling support")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Link: https://lore.kernel.org/r/57af1f28-7f57-4a96-bcd3-b7a0f2340845@moroto.mountain
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Dan Carpenter 2023-10-27 15:19:01 +03:00 committed by Jakub Kicinski
parent 7b3ba18703
commit 876f8ab523
1 changed files with 1 additions and 3 deletions

View File

@ -342,9 +342,7 @@ struct sk_buff *prp_create_tagged_frame(struct hsr_frame_info *frame,
skb = skb_copy_expand(frame->skb_std, 0,
skb_tailroom(frame->skb_std) + HSR_HLEN,
GFP_ATOMIC);
prp_fill_rct(skb, frame, port);
return skb;
return prp_fill_rct(skb, frame, port);
}
static void hsr_deliver_master(struct sk_buff *skb, struct net_device *dev,