diff mbox

ray_cs: Avoid reading past end of buffer

Message ID 20170505223841.GA20367@beast (mailing list archive)
State Accepted
Commit e48d661eb13f2f83861428f001c567fdb3f317e8
Delegated to: Kalle Valo
Headers show

Commit Message

Kees Cook May 5, 2017, 10:38 p.m. UTC
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>
---
 drivers/net/wireless/ray_cs.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

Comments

Kalle Valo May 22, 2017, 3:27 p.m. UTC | #1
Kees Cook <keescook@chromium.org> wrote:
> 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>

Patch applied to wireless-drivers-next.git, thanks.

e48d661eb13f ray_cs: Avoid reading past end of buffer
diff mbox

Patch

diff --git a/drivers/net/wireless/ray_cs.c b/drivers/net/wireless/ray_cs.c
index b94479441b0c..170cd504e8ff 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 */
 };
 
 /*===========================================================================*/
@@ -597,7 +600,7 @@  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 */