From 7414d4f64b73cc30c600b4fe0a9cbc24cedc4285 Mon Sep 17 00:00:00 2001 From: Cong Ding Date: Thu, 21 Feb 2013 15:16:40 -0800 Subject: [PATCH] drivers/block/swim3.c: fix null pointer dereference The use of pointer fs should be after the null check. Signed-off-by: Cong Ding Cc: Jens Axboe Signed-off-by: Andrew Morton Signed-off-by: Jens Axboe --- drivers/block/swim3.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/block/swim3.c b/drivers/block/swim3.c index 57763c54363a..758f2ac878cf 100644 --- a/drivers/block/swim3.c +++ b/drivers/block/swim3.c @@ -1090,10 +1090,13 @@ static const struct block_device_operations floppy_fops = { static void swim3_mb_event(struct macio_dev* mdev, int mb_state) { struct floppy_state *fs = macio_get_drvdata(mdev); - struct swim3 __iomem *sw = fs->swim3; + struct swim3 __iomem *sw; if (!fs) return; + + sw = fs->swim3; + if (mb_state != MB_FD) return;