kernel-device: expect non-NULL 'vendor' and 'product' argument in get_device_ids()

get_device_ids() in mm-kernel-device-udev.c accepts a NULL 'vendor' or
'product' argument, but the current implementation could result in a
potential NULL dereferences of the 'vendor' argument. Given that
get_device_ids() is a local helper and its only caller provides a
non-NULL 'vendor' and 'product' argument, this patch removes the NULL
checks (i.e. get_device_ids() expects non-NULL 'vendor' and 'product').

This patch also rearranges the code such that the 'vendor' argument is
updated only when the function returns TRUE, just like how the 'product'
argument is handled.
This commit is contained in:
Ben Chan
2017-08-15 09:10:44 -07:00
committed by Aleksander Morgado
parent 7ae32d6c61
commit 7e22696b34

View File

@@ -119,29 +119,21 @@ get_device_ids (GUdevDevice *device,
if (strlen (vid) != 4)
goto out;
if (vendor) {
*vendor = (guint16) (mm_utils_hex2byte (vid + 2) & 0xFF);
*vendor |= (guint16) ((mm_utils_hex2byte (vid) & 0xFF) << 8);
}
if (!pid)
pid = g_udev_device_get_property (device, "ID_MODEL_ID");
if (!pid) {
*vendor = 0;
if (!pid)
goto out;
}
if (strncmp (pid, "0x", 2) == 0)
pid += 2;
if (strlen (pid) != 4) {
*vendor = 0;
if (strlen (pid) != 4)
goto out;
}
if (product) {
*product = (guint16) (mm_utils_hex2byte (pid + 2) & 0xFF);
*product |= (guint16) ((mm_utils_hex2byte (pid) & 0xFF) << 8);
}
*vendor = (guint16) (mm_utils_hex2byte (vid + 2) & 0xFF);
*vendor |= (guint16) ((mm_utils_hex2byte (vid) & 0xFF) << 8);
*product = (guint16) (mm_utils_hex2byte (pid + 2) & 0xFF);
*product |= (guint16) ((mm_utils_hex2byte (pid) & 0xFF) << 8);
success = TRUE;