3.2.92-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Johan Hovold <johan@xxxxxxxxxx> commit 65f921647f4c89a2068478c89691f39b309b58f7 upstream. Make sure to check the number of endpoints to avoid dereferencing a NULL-pointer or accessing memory beyond the endpoint array should a malicious device lack the expected endpoints. Fixes: e0d3bafd0258 ("V4L/DVB (10954): Add cx231xx USB driver") Cc: Sri Deevi <Srinivasa.Deevi@xxxxxxxxxxxx> Signed-off-by: Johan Hovold <johan@xxxxxxxxxx> Signed-off-by: Hans Verkuil <hans.verkuil@xxxxxxxxx> Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxxx> [bwh: Backported to 3.2: adjust filename] Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx> --- drivers/media/video/cx231xx/cx231xx-audio.c | 17 +++++++++++++++-- 1 file changed, 15 insertions(+), 2 deletions(-) --- a/drivers/media/video/cx231xx/cx231xx-audio.c +++ b/drivers/media/video/cx231xx/cx231xx-audio.c @@ -680,6 +680,11 @@ static int cx231xx_audio_init(struct cx2 hs_config_info[0].interface_info. audio_index + 1]; + if (uif->altsetting[0].desc.bNumEndpoints < isoc_pipe + 1) { + err = -ENODEV; + goto err_free_card; + } + adev->end_point_addr = le16_to_cpu(uif->altsetting[0].endpoint[isoc_pipe].desc. bEndpointAddress); @@ -695,8 +700,14 @@ static int cx231xx_audio_init(struct cx2 } for (i = 0; i < adev->num_alt; i++) { - u16 tmp = - le16_to_cpu(uif->altsetting[i].endpoint[isoc_pipe].desc. + u16 tmp; + + if (uif->altsetting[i].desc.bNumEndpoints < isoc_pipe + 1) { + err = -ENODEV; + goto err_free_pkt_size; + } + + tmp = le16_to_cpu(uif->altsetting[i].endpoint[isoc_pipe].desc. wMaxPacketSize); adev->alt_max_pkt_size[i] = (tmp & 0x07ff) * (((tmp & 0x1800) >> 11) + 1); @@ -706,6 +717,8 @@ static int cx231xx_audio_init(struct cx2 return 0; +err_free_pkt_size: + kfree(adev->alt_max_pkt_size); err_free_card: snd_card_free(card);