From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Mauro Carvalho Chehab" , "Hans Verkuil" , "Sri Deevi" , "Johan Hovold" Date: Fri, 18 Aug 2017 14:13:13 +0100 Message-ID: Subject: [PATCH 3.2 20/59] [media] cx231xx-cards: fix NULL-deref at probe In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.2.92-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Johan Hovold commit 0cd273bb5e4d1828efaaa8dfd11b7928131ed149 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 Signed-off-by: Johan Hovold Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab [bwh: Backported to 3.2: adjust filename, context] Signed-off-by: Ben Hutchings --- drivers/media/video/cx231xx/cx231xx-cards.c | 45 +++++++++++++++++++++++++++---- 1 file changed, 40 insertions(+), 5 deletions(-) --- a/drivers/media/video/cx231xx/cx231xx-cards.c +++ b/drivers/media/video/cx231xx/cx231xx-cards.c @@ -1159,6 +1159,9 @@ static int cx231xx_usb_probe(struct usb_ uif = udev->actconfig->interface[dev->current_pcb_config. hs_config_info[0].interface_info.video_index + 1]; + if (uif->altsetting[0].desc.bNumEndpoints < isoc_pipe + 1) + return -ENODEV; + dev->video_mode.end_point_addr = le16_to_cpu(uif->altsetting[0]. endpoint[isoc_pipe].desc.bEndpointAddress); @@ -1176,8 +1179,12 @@ static int cx231xx_usb_probe(struct usb_ } for (i = 0; i < dev->video_mode.num_alt; i++) { - u16 tmp = le16_to_cpu(uif->altsetting[i].endpoint[isoc_pipe]. - desc.wMaxPacketSize); + u16 tmp; + + if (uif->altsetting[i].desc.bNumEndpoints < isoc_pipe + 1) + return -ENODEV; + + tmp = le16_to_cpu(uif->altsetting[i].endpoint[isoc_pipe].desc.wMaxPacketSize); dev->video_mode.alt_max_pkt_size[i] = (tmp & 0x07ff) * (((tmp & 0x1800) >> 11) + 1); cx231xx_info("Alternate setting %i, max size= %i\n", i, @@ -1189,6 +1196,9 @@ static int cx231xx_usb_probe(struct usb_ hs_config_info[0].interface_info. vanc_index + 1]; + if (uif->altsetting[0].desc.bNumEndpoints < isoc_pipe + 1) + return -ENODEV; + dev->vbi_mode.end_point_addr = le16_to_cpu(uif->altsetting[0].endpoint[isoc_pipe].desc. bEndpointAddress); @@ -1207,8 +1217,12 @@ static int cx231xx_usb_probe(struct usb_ } for (i = 0; i < dev->vbi_mode.num_alt; i++) { - u16 tmp = - le16_to_cpu(uif->altsetting[i].endpoint[isoc_pipe]. + u16 tmp; + + if (uif->altsetting[i].desc.bNumEndpoints < isoc_pipe + 1) + return -ENODEV; + + tmp = le16_to_cpu(uif->altsetting[i].endpoint[isoc_pipe]. desc.wMaxPacketSize); dev->vbi_mode.alt_max_pkt_size[i] = (tmp & 0x07ff) * (((tmp & 0x1800) >> 11) + 1); @@ -1221,6 +1235,9 @@ static int cx231xx_usb_probe(struct usb_ hs_config_info[0].interface_info. hanc_index + 1]; + if (uif->altsetting[0].desc.bNumEndpoints < isoc_pipe + 1) + return -ENODEV; + dev->sliced_cc_mode.end_point_addr = le16_to_cpu(uif->altsetting[0].endpoint[isoc_pipe].desc. bEndpointAddress); @@ -1239,7 +1256,12 @@ static int cx231xx_usb_probe(struct usb_ } for (i = 0; i < dev->sliced_cc_mode.num_alt; i++) { - u16 tmp = le16_to_cpu(uif->altsetting[i].endpoint[isoc_pipe]. + u16 tmp; + + if (uif->altsetting[i].desc.bNumEndpoints < isoc_pipe + 1) + return -ENODEV; + + tmp = le16_to_cpu(uif->altsetting[i].endpoint[isoc_pipe]. desc.wMaxPacketSize); dev->sliced_cc_mode.alt_max_pkt_size[i] = (tmp & 0x07ff) * (((tmp & 0x1800) >> 11) + 1); @@ -1254,6 +1276,11 @@ static int cx231xx_usb_probe(struct usb_ interface_info. ts1_index + 1]; + if (uif->altsetting[0].desc.bNumEndpoints < isoc_pipe + 1) { + retval = -ENODEV; + goto err_video_alt; + } + dev->ts1_mode.end_point_addr = le16_to_cpu(uif->altsetting[0].endpoint[isoc_pipe]. desc.bEndpointAddress); @@ -1272,7 +1299,14 @@ static int cx231xx_usb_probe(struct usb_ } for (i = 0; i < dev->ts1_mode.num_alt; i++) { - u16 tmp = le16_to_cpu(uif->altsetting[i]. + u16 tmp; + + if (uif->altsetting[i].desc.bNumEndpoints < isoc_pipe + 1) { + retval = -ENODEV; + goto err_video_alt; + } + + tmp = le16_to_cpu(uif->altsetting[i]. endpoint[isoc_pipe].desc. wMaxPacketSize); dev->ts1_mode.alt_max_pkt_size[i] =