From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Date: Sat, 14 Oct 2017 20:17:54 +0530
Subject: [PATCH] objtool: Print top level commands on incorrect usage
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CVE-2017-5754

Print top-level objtool commands, along with the error on incorrect
command line usage. Objtool command line parser exit's with code 129,
for incorrect usage. Convert the cmd_usage() exit code also, to maintain
consistency across objtool.

After the patch:

  $ ./objtool -j

  Unknown option: -j

  usage: objtool COMMAND [ARGS]

  Commands:
     check   Perform stack metadata validation on an object file
     orc     Generate in-place ORC unwind tables for an object file

  $ echo $?
  129

Signed-off-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1507992474-16142-1-git-send-email-kamalesh@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
(cherry picked from commit 6a93bb7e4a7d6670677d5b0eb980936eb9cc5d2e)
Signed-off-by: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
(cherry picked from commit cd75c9c55a5f288e1d3f20c48c5c4c2caf3966e8)
Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
---
 tools/objtool/objtool.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/tools/objtool/objtool.c b/tools/objtool/objtool.c
index 31e0f9143840..07f329919828 100644
--- a/tools/objtool/objtool.c
+++ b/tools/objtool/objtool.c
@@ -70,7 +70,7 @@ static void cmd_usage(void)
 
 	printf("\n");
 
-	exit(1);
+	exit(129);
 }
 
 static void handle_options(int *argc, const char ***argv)
@@ -86,9 +86,7 @@ static void handle_options(int *argc, const char ***argv)
 			break;
 		} else {
 			fprintf(stderr, "Unknown option: %s\n", cmd);
-			fprintf(stderr, "\n Usage: %s\n",
-				objtool_usage_string);
-			exit(1);
+			cmd_usage();
 		}
 
 		(*argv)++;
-- 
2.14.2

