===========
From: Kees Cook <keescook@chromium.org>
commit 1e87a2456b0227ca4ab881e19a11bb99d164e792 upstream.
A HID device could send a malicious output report that would cause the
picolcd HID driver to trigger a NULL dereference during attr file writing.
[jkosina@suse.cz: changed
report->maxfield < 1
to
report->maxfield != 1
as suggested by Bruno].
CVE-2013-2899
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: stable@kernel.org
Reviewed-by: Bruno Prémont <bonbons@linux-vserver.org>
Acked-by: Bruno Prémont <bonbons@linux-vserver.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
[Kefeng: backported to stable 3.4: adjust filename]
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
---
drivers/hid/hid-picolcd.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
@@ -1424,7 +1424,7 @@ static ssize_t picolcd_operation_mode_store(struct device *dev,
buf += 10;
cnt -= 10;
}
- if (!report)
+ if (!report || report->maxfield != 1)
return -EINVAL;
while (cnt > 0 && (buf[cnt-1] == '\n' || buf[cnt-1] == '\r'))
From: Kees Cook <keescook@chromium.org> Hi Kees, Jiri or Greg, This patch has been backported to 3.2 stable tree. It is a CVE bugfix, and looks applicable to stable-3.4. It prevents from triggering a NULL dereference during atrr file writing if a HID device send a malicious output report. NOTE: Rename file drivers/hid/hid-picolcd_core.c -> drivers/hid/hid-picolcd.c.