[PATCH AUTOSEL for 4.4 061/167] ray_cs: Avoid reading past end of buffer

Sasha Levin
2018-03-19T17:23:39Z

From: Kees Cook <keescook@chromium.org>

[ Upstream commit e48d661eb13f2f83861428f001c567fdb3f317e8 ]

Using memcpy() from a buffer that is shorter than the length copied means
the destination buffer is being filled with arbitrary data from the kernel
rodata segment. In this case, the source was made longer, since it did not
match the destination structure size. Additionally removes a needless cast.

This was found with the future CONFIG_FORTIFY_SOURCE feature.

Cc: Daniel Micay <danielmicay@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
---
drivers/net/wireless/ray_cs.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/net/wireless/ray_cs.c b/drivers/net/wireless/ray_cs.c
index 0881ba8535f4..c78abfc7bd96 100644
--- a/drivers/net/wireless/ray_cs.c
+++ b/drivers/net/wireless/ray_cs.c
@@ -247,7 +247,10 @@ static const UCHAR b4_default_startup_parms[] = {
0x04, 0x08, /* Noise gain, limit offset */
0x28, 0x28, /* det rssi, med busy offsets */
7, /* det sync thresh */
- 0, 2, 2 /* test mode, min, max */
+ 0, 2, 2, /* test mode, min, max */
+ 0, /* rx/tx delay */
+ 0, 0, 0, 0, 0, 0, /* current BSS id */
+ 0 /* hop set */
};

/*===========================================================================*/
@@ -598,7 +601,7 @@ static void init_startup_params(ray_dev_t *local)
* a_beacon_period = hops a_beacon_period = KuS
*//* 64ms = 010000 */
if (local->fw_ver == 0x55) {
- memcpy((UCHAR *) &local->sparm.b4, b4_default_startup_parms,
+ memcpy(&local->sparm.b4, b4_default_startup_parms,
sizeof(struct b4_startup_params));
/* Translate sane kus input values to old build 4/5 format */
/* i = hop time in uS truncated to 3 bytes */
--
2.14.1