linux-kernel - [PATCH 1/2] objtool: Fix double-free in .cold detection error path

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <beac5a9b7da9e8be90223459dcbe07766ae437dd.1542736240.git.jpoimboe@redhat.com>
Date:   Tue, 20 Nov 2018 11:52:15 -0600
From:   Josh Poimboeuf <jpoimboe@...hat.com>
To:     x86@...nel.org
Cc:     linux-kernel@...r.kernel.org, Artem Savkov <asavkov@...hat.com>,
        Peter Zijlstra <peterz@...radead.org>
Subject: [PATCH 1/2] objtool: Fix double-free in .cold detection error path

From: Artem Savkov <asavkov@...hat.com>

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().

Fixes: 13810435b9a7 ("objtool: Support GCC 8's cold subfunctions")
Signed-off-by: Artem Savkov <asavkov@...hat.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@...hat.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;
-- 
2.17.2