Patch "[media] cx231xx-audio: fix NULL-deref at probe" has been added to the 4.9-stable tree

This is a note to let you know that I've just added the patch titled

[media] cx231xx-audio: fix NULL-deref at probe

to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
cx231xx-audio-fix-null-deref-at-probe.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Johan Hovold <[email protected]>
Date: Mon, 13 Mar 2017 09:53:58 -0300
Subject: [media] cx231xx-audio: fix NULL-deref at probe

From: Johan Hovold <[email protected]>

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.

---
 drivers/media/usb/cx231xx/cx231xx-audio.c |   17 +++++++++++++++--
 1 file changed, 15 insertions(+), 2 deletions(-)

@@ -701,6 +701,11 @@ 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 =
 	    uif->altsetting[0].endpoint[isoc_pipe].desc.
 			bEndpointAddress;

@@ -716,8 +721,14 @@ 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);

@@ -728,6 +739,8 @@ 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);
 

Patches currently in stable-queue which might be from [email protected] are

queue-4.9/cx231xx-audio-fix-null-deref-at-probe.patch queue-4.9/usb-serial-io_ti-fix-div-by-zero-in-set_termios.patch queue-4.9/usb-chaoskey-fix-alea-quirk-on-big-endian-hosts.patch queue-4.9/usb-hub-fix-non-ss-hub-descriptor-handling.patch queue-4.9/cx231xx-cards-fix-null-deref-at-probe.patch queue-4.9/usb-serial-ftdi_sio-add-olimex-arm-usb-tiny-h-pids.patch queue-4.9/usb-serial-ftdi_sio-fix-setting-latency-for-unprivileged-users.patch queue-4.9/usb-iowarrior-fix-info-ioctl-on-big-endian-hosts.patch queue-4.9/watchdog-pcwd_usb-fix-null-deref-at-probe.patch queue-4.9/gspca-konica-add-missing-endpoint-sanity-check.patch queue-4.9/usb-serial-qcserial-add-more-lenovo-em74xx-device-ids.patch queue-4.9/usb-serial-option-add-telit-me910-support.patch queue-4.9/net-irda-irda-usb-fix-firmware-name-on-big-endian-hosts.patch queue-4.9/dib0700-fix-null-deref-at-probe.patch queue-4.9/cx231xx-audio-fix-init-error-path.patch queue-4.9/of-fdt-add-missing-allocation-failure-check.patch queue-4.9/usbvision-fix-null-deref-at-probe.patch queue-4.9/usb-serial-mct_u232-fix-big-endian-baud-rate-handling.patch queue-4.9/mceusb-fix-null-deref-at-probe.patch queue-4.9/usb-hub-fix-ss-hub-descriptor-handling.patch queue-4.9/ath9k_htc-fix-null-deref-at-probe.patch queue-4.9/usb-musb-fix-trying-to-suspend-while-active-for-otg-configurations.patch