lkml.org 
[lkml]   [2020]   [Apr]   [15]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH AUTOSEL 5.6 068/129] slcan: Don't transmit uninitialized stack data in padding
Date
From: Richard Palethorpe <rpalethorpe@suse.com>

[ Upstream commit b9258a2cece4ec1f020715fe3554bc2e360f6264 ]

struct can_frame contains some padding which is not explicitly zeroed in
slc_bump. This uninitialized data will then be transmitted if the stack
initialization hardening feature is not enabled (CONFIG_INIT_STACK_ALL).

This commit just zeroes the whole struct including the padding.

Signed-off-by: Richard Palethorpe <rpalethorpe@suse.com>
Fixes: a1044e36e457 ("can: add slcan driver for serial/USB-serial CAN adapters")
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: linux-can@vger.kernel.org
Cc: netdev@vger.kernel.org
Cc: security@kernel.org
Cc: wg@grandegger.com
Cc: mkl@pengutronix.de
Cc: davem@davemloft.net
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/can/slcan.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/drivers/net/can/slcan.c b/drivers/net/can/slcan.c
index a3664281a33fc..4dfa459ef5c73 100644
--- a/drivers/net/can/slcan.c
+++ b/drivers/net/can/slcan.c
@@ -148,7 +148,7 @@ static void slc_bump(struct slcan *sl)
u32 tmpid;
char *cmd = sl->rbuff;

- cf.can_id = 0;
+ memset(&cf, 0, sizeof(cf));

switch (*cmd) {
case 'r':
@@ -187,8 +187,6 @@ static void slc_bump(struct slcan *sl)
else
return;

- *(u64 *) (&cf.data) = 0; /* clear payload */
-
/* RTR frames may have a dlc > 0 but they never have any data bytes */
if (!(cf.can_id & CAN_RTR_FLAG)) {
for (i = 0; i < cf.can_dlc; i++) {
--
2.20.1
\
 
 \ /
  Last update: 2020-04-15 13:42    [W:0.414 / U:0.008 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site