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

@ -203,11 +203,11 @@ static int pfkey_broadcast_one(struct sk_buff *skb, struct sk_buff **skb2,
sock_hold(sk);
if (*skb2 == NULL) {
if (atomic_read(&skb->users) != 1) {
if (refcount_read(&skb->users) != 1) {
*skb2 = skb_clone(skb, allocation);
} else {
*skb2 = skb;
atomic_inc(&skb->users);
refcount_inc(&skb->users);
}
}
if (*skb2 != NULL) {