From 47810b4341ac9d2f558894bc5995e6fa2a1298f9 Mon Sep 17 00:00:00 2001 From: Laura Abbott Date: Tue, 29 Sep 2015 21:10:09 -0300 Subject: [media] si2168: Bounds check firmware 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: si2168 11-0064: found a 'Silicon Labs Si2168-B40' si2168 11-0064: downloading firmware from file 'dvb-demod-si2168-b40-01.fw' si2168 11-0064: firmware download failed -95 Kernel panic - not syncing: stack-protector: Kernel stack is corrupted in: ffffffffa085708f Add the proper check. Cc: stable@kernel.org Reported-by: Stuart Auchterlonie Reviewed-by: Antti Palosaari Signed-off-by: Laura Abbott Signed-off-by: Mauro Carvalho Chehab --- drivers/media/dvb-frontends/si2168.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/media/dvb-frontends/si2168.c b/drivers/media/dvb-frontends/si2168.c index 81788c5a44d8..821a8f481507 100644 --- a/drivers/media/dvb-frontends/si2168.c +++ b/drivers/media/dvb-frontends/si2168.c @@ -502,6 +502,10 @@ static int si2168_init(struct dvb_frontend *fe) /* firmware is in the new format */ for (remaining = fw->size; remaining > 0; remaining -= 17) { len = fw->data[fw->size - remaining]; + if (len > SI2168_ARGLEN) { + ret = -EINVAL; + break; + } memcpy(cmd.args, &fw->data[(fw->size - remaining) + 1], len); cmd.wlen = len; cmd.rlen = 1; -- cgit