This is a note to let you know that I've just added the patch titled
drivers/net/wan/hdlc_fr: Fix a double free in pvc_xmit
to the 5.11-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
drivers-net-wan-hdlc_fr-fix-a-double-free-in-pvc_xmi.patch
and it can be found in the queue-5.11 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 9c07417b0cebd5d049805d6bb86b5624ffff82b0
Author: Lv Yunlong <lyl2019@xxxxxxxxxxxxxxxx>
Date: Sun Mar 28 00:50:08 2021 -0700
drivers/net/wan/hdlc_fr: Fix a double free in pvc_xmit
[ Upstream commit 1b479fb801602b22512f53c19b1f93a4fc5d5d9d ]
In pvc_xmit, if __skb_pad(skb, pad, false) failed, it will free
the skb in the first time and goto drop. But the same skb is freed
by kfree_skb(skb) in the second time in drop.
Maintaining the original function unchanged, my patch adds a new
label out to avoid the double free if __skb_pad() failed.
Fixes: f5083d0cee08a ("drivers/net/wan/hdlc_fr: Improvements to the code of pvc_xmit")
Signed-off-by: Lv Yunlong <lyl2019@xxxxxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/net/wan/hdlc_fr.c b/drivers/net/wan/hdlc_fr.c
index 0720f5f92caa..4d9dc7d15908 100644
--- a/drivers/net/wan/hdlc_fr.c
+++ b/drivers/net/wan/hdlc_fr.c
@@ -415,7 +415,7 @@ static netdev_tx_t pvc_xmit(struct sk_buff *skb, struct net_device *dev)
if (pad > 0) { /* Pad the frame with zeros */
if (__skb_pad(skb, pad, false))
- goto drop;
+ goto out;
skb_put(skb, pad);
}
}
@@ -448,8 +448,9 @@ static netdev_tx_t pvc_xmit(struct sk_buff *skb, struct net_device *dev)
return NETDEV_TX_OK;
drop:
- dev->stats.tx_dropped++;
kfree_skb(skb);
+out:
+ dev->stats.tx_dropped++;
return NETDEV_TX_OK;
}
