From a2b2b4cd726c57ea838376c4306068cea28418a7 Mon Sep 17 00:00:00 2001 From: "Gustavo A. R. Silva" Date: Mon, 20 Nov 2017 09:00:55 -0500 Subject: [PATCH] media: c8sectpfe: fix potential NULL pointer dereference in c8sectpfe_timer_interrupt BugLink: http://bugs.launchpad.net/bugs/1758886 [ Upstream commit baed3c4bc4c13de93e0dba0a26d601411ebcb389 ] _channel_ is being dereferenced before it is null checked, hence there is a potential null pointer dereference. Fix this by moving the pointer dereference after _channel_ has been null checked. This issue was detected with the help of Coccinelle. Fixes: c5f5d0f99794 ("[media] c8sectpfe: STiH407/10 Linux DVB demux support") Signed-off-by: Gustavo A. R. Silva Acked-by: Patrice Chotard Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman Signed-off-by: Thadeu Lima de Souza Cascardo --- drivers/media/platform/sti/c8sectpfe/c8sectpfe-core.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/media/platform/sti/c8sectpfe/c8sectpfe-core.c b/drivers/media/platform/sti/c8sectpfe/c8sectpfe-core.c index a0acee7671b1..8bd19e61846d 100644 --- a/drivers/media/platform/sti/c8sectpfe/c8sectpfe-core.c +++ b/drivers/media/platform/sti/c8sectpfe/c8sectpfe-core.c @@ -83,7 +83,7 @@ static void c8sectpfe_timer_interrupt(struct timer_list *t) static void channel_swdemux_tsklet(unsigned long data) { struct channel_info *channel = (struct channel_info *)data; - struct c8sectpfei *fei = channel->fei; + struct c8sectpfei *fei; unsigned long wp, rp; int pos, num_packets, n, size; u8 *buf; @@ -91,6 +91,8 @@ static void channel_swdemux_tsklet(unsigned long data) if (unlikely(!channel || !channel->irec)) return; + fei = channel->fei; + wp = readl(channel->irec + DMA_PRDS_BUSWP_TP(0)); rp = readl(channel->irec + DMA_PRDS_BUSRP_TP(0)); -- 2.39.2