This is a note to let you know that I've just added the patch titled media: c8sectpfe: fix potential NULL pointer dereference in c8sectpfe_timer_interrupt to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: media-c8sectpfe-fix-potential-null-pointer-dereference-in-c8sectpfe_timer_interrupt.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From foo@baz Thu Mar 22 14:40:24 CET 2018 From: "Gustavo A. R. Silva" <garsilva@xxxxxxxxxxxxxx> Date: Mon, 20 Nov 2017 09:00:55 -0500 Subject: media: c8sectpfe: fix potential NULL pointer dereference in c8sectpfe_timer_interrupt From: "Gustavo A. R. Silva" <garsilva@xxxxxxxxxxxxxx> [ 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 <garsilva@xxxxxxxxxxxxxx> Acked-by: Patrice Chotard <patrice.chotard@xxxxxx> Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/media/platform/sti/c8sectpfe/c8sectpfe-core.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- 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(un 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(unsig 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)); Patches currently in stable-queue which might be from garsilva@xxxxxxxxxxxxxx are queue-4.9/media-c8sectpfe-fix-potential-null-pointer-dereference-in-c8sectpfe_timer_interrupt.patch