From 7bd07d0aae76e8331183bbbc2a60cfe7547fafcf Mon Sep 17 00:00:00 2001 From: Laura Abbott Date: Tue, 29 Sep 2015 21:10:10 -0300 Subject: [PATCH] [media] si2157: Bounds check firmware [ Upstream commit a828d72df216c36e9c40b6c24dc4b17b6f7b5a76 ] When reading the firmware and sending commands, the length must be bounds checked to avoid overrunning the size of the command buffer and smashing the stack if the firmware is not in the expected format. Add the proper check. Cc: stable@kernel.org Signed-off-by: Laura Abbott Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Sasha Levin --- drivers/media/tuners/si2157.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/media/tuners/si2157.c b/drivers/media/tuners/si2157.c index cf97142e01e6..a9032717c759 100644 --- a/drivers/media/tuners/si2157.c +++ b/drivers/media/tuners/si2157.c @@ -157,6 +157,10 @@ static int si2157_init(struct dvb_frontend *fe) for (remaining = fw->size; remaining > 0; remaining -= 17) { len = fw->data[fw->size - remaining]; + if (len > SI2157_ARGLEN) { + dev_err(&s->client->dev, "Bad firmware length\n"); + goto err; + } memcpy(cmd.args, &fw->data[(fw->size - remaining) + 1], len); cmd.wlen = len; cmd.rlen = 1;