From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Stuart Auchterlonie , Antti Palosaari , Laura Abbott , Mauro Carvalho Chehab Subject: [PATCH 4.1 16/86] [media] si2168: Bounds check firmware Date: Fri, 6 Nov 2015 11:22:15 -0800 Message-Id: <20151106192206.205832029@linuxfoundation.org> In-Reply-To: <20151106192205.351595349@linuxfoundation.org> References: <20151106192205.351595349@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Sender: linux-kernel-owner@vger.kernel.org List-ID: 4.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Laura Abbott commit 47810b4341ac9d2f558894bc5995e6fa2a1298f9 upstream. 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. Reported-by: Stuart Auchterlonie Reviewed-by: Antti Palosaari Signed-off-by: Laura Abbott Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Greg Kroah-Hartman --- drivers/media/dvb-frontends/si2168.c | 4 ++++ 1 file changed, 4 insertions(+) --- a/drivers/media/dvb-frontends/si2168.c +++ b/drivers/media/dvb-frontends/si2168.c @@ -457,6 +457,10 @@ static int si2168_init(struct dvb_fronte /* 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;