play: Handle empty arguments to --key-map gracefully.

Executing para_play with an empty argument to --key-map results in
a read which starts one byte past the allocated buffer:

	==24163== Invalid read of size 1
	==24163==    at 0x402A1DA: index (mc_replace_strmem.c:223)
	==24163==    by 0x804DA22: main (play.c:187)
	==24163==  Address 0x498e331 is 0 bytes after a block of size 1 alloc'd

This patch fixes the issue by rejecting empty arguments as invalid.

diff --git a/play.c b/play.c
index 61c30aed08b131384e099a945cfed3011b9a0f97..1b3cc933926da62c9c6f6914759b66f015ac61ee 100644 (file)
--- a/play.c
+++ b/play.c
@@ -184,10 +184,10 @@ static void parse_config_or_die(int argc, char *argv[])
                loglevel = get_loglevel_by_name(conf.loglevel_arg);
        }
        for (i = 0; i < conf.key_map_given; i++) {
-               char *s = strchr(conf.key_map_arg[i] + 1, ':');
-               if (s)
+               char *kma = conf.key_map_arg[i];
+               if (*kma && strchr(kma + 1, ':'))
                        continue;
-               PARA_EMERG_LOG("invalid key map arg: %s\n", conf.key_map_arg[i]);
+               PARA_EMERG_LOG("invalid key map arg: %s\n", kma);
                goto err;
        }
        free(config_file);