tc: m_bpf: fix next arg selection after tc opcode

Next argument after the tc opcode/verdict is optional, using NEXT_ARG()
requires to have another argument after that one otherwise tc will bail
out. Therefore, we need to advance to the next argument manually as done
elsewhere.

Fixes: 86ab59a6 ("tc: add support for BPF based actions")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jiri Pirko <jiri@resnulli.us>

tc/m_bpf.c

@@ -89,20 +89,25 @@ static int parse_bpf(struct action_util *a, int *argc_p, char ***argv_p,
 	if (argc) {
 		if (matches(*argv, "reclassify") == 0) {
 			parm.action = TC_ACT_RECLASSIFY;
-			NEXT_ARG();
+			argc--;
+			argv++;
 		} else if (matches(*argv, "pipe") == 0) {
 			parm.action = TC_ACT_PIPE;
-			NEXT_ARG();
+			argc--;
+			argv++;
 		} else if (matches(*argv, "drop") == 0 ||
 			   matches(*argv, "shot") == 0) {
 			parm.action = TC_ACT_SHOT;
-			NEXT_ARG();
+			argc--;
+			argv++;
 		} else if (matches(*argv, "continue") == 0) {
 			parm.action = TC_ACT_UNSPEC;
-			NEXT_ARG();
+			argc--;
+			argv++;
 		} else if (matches(*argv, "pass") == 0) {
 			parm.action = TC_ACT_OK;
-			NEXT_ARG();
+			argc--;
+			argv++;
 		}
 	}