Fix CVE-2019-3701 (rhbz 1663729 1663730)

CVE-2019-3701.patch

@@ -0,0 +1,42 @@
+From linux-netdev  Thu Jan 03 12:26:34 2019
+From: Oliver Hartkopp <socketcan () hartkopp ! net>
+Date: Thu, 03 Jan 2019 12:26:34 +0000
+To: linux-netdev
+Subject: [PATCH] can: gw: ensure DLC boundaries after CAN frame modification
+Message-Id: <20190103122634.2530-1-socketcan () hartkopp ! net>
+X-MARC-Message: https://marc.info/?l=linux-netdev&m=154651842302479
+
+The CAN frame modification rules allow bitwise logical operations which can
+be also applied to the can_dlc field. Ensure the manipulation result to
+maintain the can_dlc boundaries so that the CAN drivers do not accidently
+write arbitrary content beyond the data registers in the CAN controllers
+I/O mem when processing can-gw manipulated outgoing frames. When passing these
+frames to user space this issue did not have any effect to the kernel or any
+leaked data as we always strictly copy sizeof(struct can_frame) bytes.
+
+Reported-by: Muyu Yu <ieatmuttonchuan@gmail.com>
+Reported-by: Marcus Meissner <meissner@suse.de>
+Tested-by: Muyu Yu <ieatmuttonchuan@gmail.com>
+Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
+Cc: linux-stable <stable@vger.kernel.org> # >= v3.2
+---
+ net/can/gw.c | 4 ++++
+ 1 file changed, 4 insertions(+)
+
+diff --git a/net/can/gw.c b/net/can/gw.c
+index faa3da88a127..9000d9b8a133 100644
+--- a/net/can/gw.c
++++ b/net/can/gw.c
+@@ -418,6 +418,10 @@ static void can_can_gw_rcv(struct sk_buff *skb, void *data)
+ 
+ 	/* check for checksum updates when the CAN frame has been modified */
+ 	if (modidx) {
++		/* ensure DLC boundaries after the different mods */
++		if (cf->can_dlc > 8)
++			cf->can_dlc = 8;
++
+ 		if (gwj->mod.csumfunc.crc8)
+ 			(*gwj->mod.csumfunc.crc8)(cf, &gwj->mod.csum.crc8);
+ 
+-- 
+2.19.2

kernel.spec

@@ -633,6 +633,9 @@ Patch516: asus-fx503-keyb.patch
 # rhbz 1661961 patch merged upstream in 4.20
 Patch517: 0001-Bluetooth-btsdio-Do-not-bind-to-non-removable-BCM434.patch
 
+# CVE-2019-3701 rhbz 1663729 1663730
+Patch518: CVE-2019-3701.patch
+
 # END OF PATCH DEFINITIONS
 
 %endif
@@ -1884,6 +1887,9 @@ fi
 #
 #
 %changelog
+* Tue Jan 07 2019 Justin M. Forbes <jforbes@fedoraproject.org>
+- Fix CVE-2019-3701 (rhbz 1663729 1663730)
+
 * Mon Jan  7 2019 Hans de Goede <hdegoede@redhat.com>
 - Add patch to fix bluetooth on RPI 3B+ registering twice (rhbz#1661961)