HID: core: Avoid uninitialized buffer access

commit 79b568b9d0c7c5d81932f4486d50b38efdd6da6d upstream.

hid_connect adds various strings to the buffer but they're all
conditional. You can find circumstances where nothing would be written
to it but the kernel will still print the supposedly empty buffer with
printk. This leads to corruption on the console/in the logs.

Ensure buf is initialized to an empty string.

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
[dvhart: Initialize string to "" rather than assign buf[0] = NULL;]
Cc: Jiri Kosina <jikos@kernel.org>
Cc: linux-input@vger.kernel.org
Signed-off-by: Darren Hart <dvhart@linux.intel.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>

diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c
index 5ed3a7b91b4cbe92f302caa1f6698685554bfab7..fb16c812816aaaf912381218342df02a805cd58b 100644 (file)
--- a/drivers/hid/hid-core.c
+++ b/drivers/hid/hid-core.c
@@ -1561,7 +1561,7 @@ int hid_connect(struct hid_device *hdev, unsigned int connect_mask)
                "Multi-Axis Controller"
        };
        const char *type, *bus;
-       char buf[64];
+       char buf[64] = "";
        unsigned int i;
        int len;
        int ret;