| From | Ben Hutchings <> | Date | Wed, 27 Apr 2016 01:02:21 +0200 | Subject | [PATCH 3.16 203/217] sh_eth: fix NULL pointer dereference in sh_eth_ring_format() |
| |
3.16.35-rc1 review patch. If anyone has any objections, please let me know.
------------------
From: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
[ Upstream commit c1b7fca65070bfadca94dd53a4e6b71cd4f69715 ]
In a low memory situation, if netdev_alloc_skb() fails on a first RX ring loop iteration in sh_eth_ring_format(), 'rxdesc' is still NULL. Avoid kernel oops by adding the 'rxdesc' check after the loop.
Reported-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> --- drivers/net/ethernet/renesas/sh_eth.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
--- a/drivers/net/ethernet/renesas/sh_eth.c +++ b/drivers/net/ethernet/renesas/sh_eth.c @@ -1162,7 +1162,8 @@ static void sh_eth_ring_format(struct ne mdp->dirty_rx = (u32) (i - mdp->num_rx_ring); /* Mark the last entry as wrapping the ring. */ - rxdesc->status |= cpu_to_edmac(mdp, RD_RDEL); + if (rxdesc) + rxdesc->status |= cpu_to_edmac(mdp, RD_RDEL); memset(mdp->tx_ring, 0, tx_ringsize);
|