[PATCH] DMA: pl330: fix null pointer dereference in pl330_chan_ctrl()

Mans Rullgard mans.rullgard at linaro.org
Wed Jan 25 07:11:32 EST 2012


This fixes the thrd->req_running field being accessed before thrd
is checked for null.  The error was introduced in abb959f
(ARM: 7237/1: PL330: Fix driver freeze).

Signed-off-by: Mans Rullgard <mans.rullgard at linaro.org>
---
 drivers/dma/pl330.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c
index add07e0..6278443 100644
--- a/drivers/dma/pl330.c
+++ b/drivers/dma/pl330.c
@@ -1568,12 +1568,13 @@ static int pl330_chan_ctrl(void *ch_id, enum pl330_chan_op op)
 	struct pl330_thread *thrd = ch_id;
 	struct pl330_dmac *pl330;
 	unsigned long flags;
-	int ret = 0, active = thrd->req_running;
+	int ret = 0, active;
 
 	if (!thrd || thrd->free || thrd->dmac->state == DYING)
 		return -EINVAL;
 
 	pl330 = thrd->dmac;
+	active = thrd->req_running;
 
 	spin_lock_irqsave(&pl330->lock, flags);
 
-- 
1.7.8.4




More information about the linux-arm-kernel mailing list