net: convert sk_buff.users from atomic_t to refcount_t

refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.

Signed-off-by: Elena Reshetova <[email protected]>
Signed-off-by: Hans Liljestrand <[email protected]>
Signed-off-by: Kees Cook <[email protected]>
Signed-off-by: David Windsor <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
This commit is contained in:
Reshetova, Elena 2017-06-30 13:07:58 +03:00 • committed by David S. Miller
commit 633547973f
21 changed files with 67 additions and 67 deletions

View file

@ -194,7 +194,7 @@ struct sock *cookie_v6_check(struct sock *sk, struct sk_buff *skb)
if (ipv6_opt_accepted(sk, skb, &TCP_SKB_CB(skb)->header.h6) ||
np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo ||
np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim) {
atomic_inc(&skb->users);
refcount_inc(&skb->users);
ireq->pktopts = skb;
}

View file

@ -734,7 +734,7 @@ static void tcp_v6_init_req(struct request_sock *req,
np->rxopt.bits.rxinfo ||
np->rxopt.bits.rxoinfo || np->rxopt.bits.rxhlim ||
np->rxopt.bits.rxohlim || np->repflow)) {
atomic_inc(&skb->users);
refcount_inc(&skb->users);
ireq->pktopts = skb;
}
}