Android: Allow wpa_supplicant to write files to osu-info dir

This commit allows any process running with group id of AID_WIFI to
read/write files to osu-info directory. Also, it allows other users to
read and search the osu-info directory.

This fixes issues with hs20-osu-client creating a directory for
wpa_supplicant use without wpa_supplicant actually having privileges to
write there on Android where the wpa_supplicant process does not run as
root.

Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>

hs20/client/osu_client.c

@@ -2339,12 +2339,23 @@ static int cmd_signup(struct hs20_osu_client *ctx, int no_prod_assoc,
 		return -1;
 
 	snprintf(fname, sizeof(fname), "%s/osu-info", dir);
-	if (mkdir(fname, S_IRWXU | S_IRWXG) < 0 && errno != EEXIST) {
+	if (mkdir(fname, S_IRWXU | S_IRWXG | S_IROTH | S_IXOTH) < 0 &&
+	    errno != EEXIST) {
 		wpa_printf(MSG_INFO, "mkdir(%s) failed: %s",
 			   fname, strerror(errno));
 		return -1;
 	}
 
+#ifdef ANDROID
+	/* Allow processes running with Group ID as AID_WIFI
+	 * to read/write files from osu-info directory
+	 */
+	if (chown(fname, -1, AID_WIFI)) {
+		wpa_printf(MSG_INFO, "Could not chown osu-info directory: %s",
+			   strerror(errno));
+	}
+#endif /* ANDROID */
+
 	snprintf(buf, sizeof(buf), "SET osu_dir %s", fname);
 	if (wpa_command(ifname, buf) < 0) {
 		wpa_printf(MSG_INFO, "Failed to configure osu_dir to wpa_supplicant");