UHID allows short writes so user-space can omit unused fields. We
automatically set them to 0 in the kernel. However, the 64/32 bit
compat-handler didn't do that in the UHID_CREATE fallback. This will
reveal random kernel heap data (of random size, even) to user-space.

Reported-by: Ben Hutchings <[email protected]>
Signed-off-by: David Herrmann <[email protected]>
Cc: [email protected]
---
 drivers/hid/uhid.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/hid/uhid.c b/drivers/hid/uhid.c
index 93b00d7..cedc6da 100644
--- a/drivers/hid/uhid.c
+++ b/drivers/hid/uhid.c
@@ -287,7 +287,7 @@ static int uhid_event_from_user(const char __user *buffer, 
size_t len,
                         */
                        struct uhid_create_req_compat *compat;
 
-                       compat = kmalloc(sizeof(*compat), GFP_KERNEL);
+                       compat = kzalloc(sizeof(*compat), GFP_KERNEL);
                        if (!compat)
                                return -ENOMEM;
 
-- 
1.8.4.2

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