[PATCH 1/2] um: vector: Fix a potential NULL pointer dereference in 'vector_net_open()'

From: Christophe JAILLET
Date: Fri Dec 28 2018 - 04:57:45 EST


'create_queue()' returns NULL in case of memory allocation failure. So we
must check if it succeeds in order to avoid potential NULL pointer
dereference.

For 'vp->rx_queue', the dereference would occur just one line after the
failed allocation. For 'vp->tx_queue', it would occur later during normal
processing.

Fixes: 49da7e64f33e ("High Performance UML Vector Network Driver")
Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>
---
arch/um/drivers/vector_kern.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/arch/um/drivers/vector_kern.c b/arch/um/drivers/vector_kern.c
index 046fa9ea0ccc..5b917716289d 100644
--- a/arch/um/drivers/vector_kern.c
+++ b/arch/um/drivers/vector_kern.c
@@ -1182,6 +1182,8 @@ static int vector_net_open(struct net_device *dev)
vp->rx_header_size,
MAX_IOV_SIZE
);
+ if (!vp->rx_queue)
+ goto out_close;
vp->rx_queue->queue_depth = get_depth(vp->parsed);
} else {
vp->header_rxbuffer = kmalloc(
@@ -1198,6 +1200,8 @@ static int vector_net_open(struct net_device *dev)
vp->header_size,
MAX_IOV_SIZE
);
+ if (!vp->tx_queue)
+ goto out_close;
} else {
vp->header_txbuffer = kmalloc(vp->header_size, GFP_KERNEL);
if (vp->header_txbuffer == NULL)
--
2.19.1