[ 018/143] b43: stop format string leaking into error msgs

Willy Tarreau
2014-05-12T01:53:42Z

From: Kees Cook <keescook@chromium.org>

commit e0e29b683d6784ef59bbc914eac85a04b650e63c upstream

The module parameter "fwpostfix" is userspace controllable, unfiltered,
and is used to define the firmware filename. b43_do_request_fw() populates
ctx->errors[] on error, containing the firmware filename. b43err()
parses its arguments as a format string. For systems with b43 hardware,
this could lead to a uid-0 to ring-0 escalation.

CVE-2013-2852

Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
---
drivers/net/wireless/b43/main.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/wireless/b43/main.c b/drivers/net/wireless/b43/main.c
index 94dae56..3cf2472 100644
--- a/drivers/net/wireless/b43/main.c
+++ b/drivers/net/wireless/b43/main.c
@@ -2257,7 +2257,7 @@ static int b43_request_firmware(struct b43_wldev *dev)
for (i = 0; i < B43_NR_FWTYPES; i++) {
errmsg = ctx->errors[i];
if (strlen(errmsg))
- b43err(dev->wl, errmsg);
+ b43err(dev->wl, "%s", errmsg);
}
b43_print_fw_helptext(dev->wl, 1);
err = -ENOENT;
--
1.7.12.2.21.g234cd45.dirty