[PATCH AUTOSEL for 3.18 25/53] HSI: ssi_protocol: double free in ssip_pn_xmit()

From: Sasha Levin
Date: Thu Mar 08 2018 - 00:10:33 EST


From: Dan Carpenter <dan.carpenter@xxxxxxxxxx>

[ Upstream commit 3026050179a3a9a6f5c892c414b5e36ecf092081 ]

If skb_pad() fails then it frees skb and we don't need to free it again
at the end of the function.

Fixes: dc7bf5d7 ("HSI: Introduce driver for SSI Protocol")
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Signed-off-by: Sebastian Reichel <sre@xxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
---
drivers/hsi/clients/ssi_protocol.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/hsi/clients/ssi_protocol.c b/drivers/hsi/clients/ssi_protocol.c
index e5c7a969f28b..0cb78f30696b 100644
--- a/drivers/hsi/clients/ssi_protocol.c
+++ b/drivers/hsi/clients/ssi_protocol.c
@@ -976,7 +976,7 @@ static int ssip_pn_xmit(struct sk_buff *skb, struct net_device *dev)
goto drop;
/* Pad to 32-bits - FIXME: Revisit*/
if ((skb->len & 3) && skb_pad(skb, 4 - (skb->len & 3)))
- goto drop;
+ goto inc_dropped;

/*
* Modem sends Phonet messages over SSI with its own endianess...
@@ -1028,8 +1028,9 @@ static int ssip_pn_xmit(struct sk_buff *skb, struct net_device *dev)
drop2:
hsi_free_msg(msg);
drop:
- dev->stats.tx_dropped++;
dev_kfree_skb(skb);
+inc_dropped:
+ dev->stats.tx_dropped++;

return 0;
}
--
2.14.1