shinys000114/linux
1
0
Fork 0
mirror of https://github.com/hardkernel/linux.git synced 2026-06-09 20:32:04 +09:00
Code Issues Packages Projects Releases Wiki Activity

net: fix socket refcounting in skb_complete_wifi_ack()

Browse Source 
[ Upstream commit dd4f10722a ]

TX skbs do not necessarily hold a reference on skb->sk->sk_refcnt
By the time TX completion happens, sk_refcnt might be already 0.

sock_hold()/sock_put() would then corrupt critical state, like
sk_wmem_alloc.

Fixes: bf7fa551e0 ("mac80211: Resolve sk_refcnt/sk_wmem_alloc issue in wifi ack path")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Alexander Duyck <alexander.h.duyck@intel.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Soheil Hassas Yeganeh <soheil@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Eric Dumazet
2017-03-03 21:01:02 -08:00
committed by Greg Kroah-Hartman
parent 2681a7853a
commit 9e7683301b
1 changed files with 8 additions and 7 deletions
Download Patch File Download Diff File Expand all files Collapse all files

15
net/core/skbuff.c
View File

@@ -3735,7 +3735,7 @@ void skb_complete_wifi_ack(struct sk_buff *skb, bool acked)
{ {
struct sock *sk = skb->sk; struct sock *sk = skb->sk;
struct sock_exterr_skb *serr; struct sock_exterr_skb *serr;
int err; int err = 1;
skb->wifi_acked_valid = 1; skb->wifi_acked_valid = 1;
skb->wifi_acked = acked; skb->wifi_acked = acked;
@@ -3745,14 +3745,15 @@ void skb_complete_wifi_ack(struct sk_buff *skb, bool acked)
serr->ee.ee_errno = ENOMSG; serr->ee.ee_errno = ENOMSG;
serr->ee.ee_origin = SO_EE_ORIGIN_TXSTATUS; serr->ee.ee_origin = SO_EE_ORIGIN_TXSTATUS;
/* take a reference to prevent skb_orphan() from freeing the socket */ /* Take a reference to prevent skb_orphan() from freeing the socket,
sock_hold(sk); * but only if the socket refcount is not zero.
*/
err = sock_queue_err_skb(sk, skb); if (likely(atomic_inc_not_zero(&sk->sk_refcnt))) {
err = sock_queue_err_skb(sk, skb);
sock_put(sk);
}
if (err) if (err)
kfree_skb(skb); kfree_skb(skb);
sock_put(sk);
} }
EXPORT_SYMBOL_GPL(skb_complete_wifi_ack); EXPORT_SYMBOL_GPL(skb_complete_wifi_ack);