[PATCH] mac80211: fix access to null skb

[PATCH] mac80211: fix access to null skb

[Luis Carlos Cobo]

Without this patch, if xmit_skb is null but net_ratelimit() returns 0 we would
go to the else branch and access the null xmit_skb. Pointed out by Johannes
Berg.

Signed-off-by: Luis Carlos Cobo <luisca@cozybit.com>
---
 net/mac80211/rx.c |    6 +++---
 1 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
index e8b89c8..bc66d99 100644
--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c
@@ -1300,11 +1300,11 @@ ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
 		if (is_multicast_ether_addr(skb->data)) {
 			if (*mesh_ttl > 0) {
 				xmit_skb = skb_copy(skb, GFP_ATOMIC);
-				if (!xmit_skb && net_ratelimit())
+				if (xmit_skb)
+					xmit_skb->pkt_type = PACKET_OTHERHOST;
+				else if (net_ratelimit())
 					printk(KERN_DEBUG "%s: failed to clone "
 					       "multicast frame\n", dev->name);
-				else
-					xmit_skb->pkt_type = PACKET_OTHERHOST;
 			} else
 				IEEE80211_IFSTA_MESH_CTR_INC(&sdata->u.sta,
 							     dropped_frames_ttl);
-- 
1.5.4.3

Re: [PATCH] mac80211: fix access to null skb

[Johannes Berg]

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On Mon, 2008-05-05 at 12:29 -0700, Luis Carlos Cobo wrote:
> Without this patch, if xmit_skb is null but net_ratelimit() returns 0 we would
> go to the else branch and access the null xmit_skb. Pointed out by Johannes
> Berg.

Thanks Luis, for both patches.

johannes

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