up-input.c: fix bitmap check

In up_input_coldplug(), some checks are done on the input device found in order
to detect if it's a lid switch or not.

The following one is problematic :

         /* convert to a bitmask */
         num_bits = up_input_str_to_bitmask (contents, bitmask, sizeof (bitmask));
         if (num_bits != 1) {
                 g_debug ("not one bitmask entry for %s", native_path);
                 ret = FALSE;
                 goto out;
         }

Checking if there's only 1 bit set is wrong. It's nice if you have a x86 with
acpi using 1 input device for the lid switch but it's not always nice.
One can create input devices with gpios-keys like this:

 static struct gpio_keys_button keys[] = {
         {
                 .code = SW_LID,
                 .gpio = ...,
                 .type = EV_SW,
                 .desc = "Lid Switch",
         },
         {
                 .code = SW_RFKILL_ALL,
                 .gpio = ...,
                 .type = EV_SW,
                 .desc = "rfkill",
         },
 };

The resulting SW bitmap will be 9 and thus there are 2 bits sets and due to the
mentionned check, the device is ignored by upower.

As a fix, I'm checking if the number of bits is between 0 and SW_CNT
bits.

Signed-off-by: Arnaud Patard <arnaud.patard@rtp-net.org>
Signed-off-by: Richard Hughes <richard@hughsie.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/src/linux/up-input.c b/src/linux/up-input.c
index 8721ee4..553bd9a 100644
--- a/src/linux/up-input.c
+++ b/src/linux/up-input.c
@@ -197,8 +197,8 @@ up_input_coldplug (UpInput *input, UpDaemon *daemon, GUdevDevice *d)
 
 	/* convert to a bitmask */
 	num_bits = up_input_str_to_bitmask (contents, bitmask, sizeof (bitmask));
-	if (num_bits != 1) {
-		g_debug ("not one bitmask entry for %s", native_path);
+	if ((num_bits == 0) || (num_bits >= SW_CNT)) {
+		g_debug ("invalid bitmask entry for %s", native_path);
 		ret = FALSE;
 		goto out;
 	}