From: Artem Savkov <asavkov@redhat.com>
Date: Tue, 20 Nov 2018 11:52:15 -0600
Subject: objtool: Fix double-free in .cold detection error path
Git-commit: 0b9301fb632f7111a3293a30cc5b20f1b82ed08d
Patch-mainline: v4.20-rc5
References: bsc#1058115

If read_symbols() fails during second list traversal (the one dealing
with ".cold" subfunctions) it frees the symbol, but never deletes it
from the list/hash_table resulting in symbol being freed again in
elf_close(). Fix it by just returning an error, leaving cleanup to
elf_close().

Signed-off-by: Artem Savkov <asavkov@redhat.com>
Signed-off-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>
Fixes: 13810435b9a7 ("objtool: Support GCC 8's cold subfunctions")
Link: http://lkml.kernel.org/r/beac5a9b7da9e8be90223459dcbe07766ae437dd.1542736240.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Miroslav Benes <mbenes@suse.cz>
---
 tools/objtool/elf.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/tools/objtool/elf.c
+++ b/tools/objtool/elf.c
@@ -310,7 +310,7 @@ static int read_symbols(struct elf *elf)
 				if (!pfunc) {
 					WARN("%s(): can't find parent function",
 					     sym->name);
-					goto err;
+					return -1;
 				}
 
 				sym->pfunc = pfunc;