From 70b9b24d4d240ff5f6087bca4013c6969af275ab Mon Sep 17 00:00:00 2001 From: Sachin Kamat Date: Thu, 22 Nov 2012 00:11:09 +0900 Subject: [PATCH] ARM: S3C24XX: Fix potential NULL pointer dereference error chan->end is tested for being NULL. However in the event that it is NULL, the subsequent assignment statement would lead to NULL pointer dereference. Thus dereferencing it only when it is not NULL. Signed-off-by: Sachin Kamat Signed-off-by: Kukjin Kim --- arch/arm/plat-s3c24xx/dma.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/arch/arm/plat-s3c24xx/dma.c b/arch/arm/plat-s3c24xx/dma.c index db98e7021f0d..0abd1c469887 100644 --- a/arch/arm/plat-s3c24xx/dma.c +++ b/arch/arm/plat-s3c24xx/dma.c @@ -473,12 +473,13 @@ int s3c2410_dma_enqueue(enum dma_ch channel, void *id, pr_debug("dma%d: %s: buffer %p queued onto non-empty channel\n", chan->number, __func__, buf); - if (chan->end == NULL) + if (chan->end == NULL) { pr_debug("dma%d: %s: %p not empty, and chan->end==NULL?\n", chan->number, __func__, chan); - - chan->end->next = buf; - chan->end = buf; + } else { + chan->end->next = buf; + chan->end = buf; + } } /* if necessary, update the next buffer field */