| Message ID | 1370287723-30168-1-git-send-email-pablo@netfilter.org |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
From: Pablo Neira Ayuso <pablo@netfilter.org> Date: Mon, 3 Jun 2013 21:28:43 +0200 > Eric Dumazet spotted that we have to check skb->head instead > of skb->data as skb->head points to the beginning of the > data area of the skbuff. Similarly, we have to initialize the > skb->head pointer, not skb->data in __alloc_skb_head. > > After this fix, netlink crashes in the release path of the > sk_buff, so let's fix that as well. > > This bug was introduced in (0ebd0ac net: add function to > allocate sk_buff head without data area). > > Reported-by: Eric Dumazet <eric.dumazet@gmail.com> > Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Applied and queued up for -stable, thanks. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/net/core/skbuff.c b/net/core/skbuff.c index d629891..98ed66a 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -195,7 +195,7 @@ struct sk_buff *__alloc_skb_head(gfp_t gfp_mask, int node) * the tail pointer in struct sk_buff! */ memset(skb, 0, offsetof(struct sk_buff, tail)); - skb->data = NULL; + skb->head = NULL; skb->truesize = sizeof(struct sk_buff); atomic_set(&skb->users, 1); @@ -611,7 +611,7 @@ static void skb_release_head_state(struct sk_buff *skb) static void skb_release_all(struct sk_buff *skb) { skb_release_head_state(skb); - if (likely(skb->data)) + if (likely(skb->head)) skb_release_data(skb); } diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c index 12ac6b4..d0b3dd6 100644 --- a/net/netlink/af_netlink.c +++ b/net/netlink/af_netlink.c @@ -747,7 +747,7 @@ static void netlink_skb_destructor(struct sk_buff *skb) atomic_dec(&ring->pending); sock_put(sk); - skb->data = NULL; + skb->head = NULL; } #endif if (skb->sk != NULL)
Eric Dumazet spotted that we have to check skb->head instead of skb->data as skb->head points to the beginning of the data area of the skbuff. Similarly, we have to initialize the skb->head pointer, not skb->data in __alloc_skb_head. After this fix, netlink crashes in the release path of the sk_buff, so let's fix that as well. This bug was introduced in (0ebd0ac net: add function to allocate sk_buff head without data area). Reported-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> --- net/core/skbuff.c | 4 ++-- net/netlink/af_netlink.c | 2 +- 2 files changed, 3 insertions(+), 3 deletions(-)