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From:   Artem Savkov <asavkov@redhat.com>
To:     Josh Poimboeuf <jpoimboe@redhat.com>
Cc:     Peter Zijlstra <peterz@infradead.org>,
        linux-kernel@vger.kernel.org, Artem Savkov <asavkov@redhat.com>
Subject: [PATCH v4 1/2] objtool: fix failed cold symbol doublefree
Date:   Tue, 20 Nov 2018 09:05:47 +0100
Message-Id: <20181120080548.26082-2-asavkov@redhat.com>
In-Reply-To: <20181120080548.26082-1-asavkov@redhat.com>
References: <20181112125519.26855-1-asavkov@redhat.com>
 <20181120080548.26082-1-asavkov@redhat.com>
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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 by just returning an error leaving cleanup to
elf_close().

Fixes: 13810435b9a7 ("objtool: Support GCC 8's cold subfunctions")
Signed-off-by: Artem Savkov <asavkov@redhat.com>
---
 tools/objtool/elf.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/objtool/elf.c b/tools/objtool/elf.c
index 6dbb9fae0f9d..e7a7ac40e045 100644
--- a/tools/objtool/elf.c
+++ b/tools/objtool/elf.c
@@ -312,7 +312,7 @@ 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;
-- 
2.19.1