linux-kernel - [PATCH 3.16 062/254] kdb: Fix handling of kallsyms_symbol

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: <lsq.1519831218.655444379@decadent.org.uk>
Date:   Wed, 28 Feb 2018 15:20:18 +0000
From:   Ben Hutchings <ben@...adent.org.uk>
To:     linux-kernel@...r.kernel.org, stable@...r.kernel.org
CC:     akpm@...ux-foundation.org,
        "Dan Carpenter" <dan.carpenter@...cle.com>,
        "Jason Wessel" <jason.wessel@...driver.com>,
        "Daniel Thompson" <daniel.thompson@...aro.org>
Subject: [PATCH 3.16 062/254] kdb: Fix handling of kallsyms_symbol_next()
 return value

3.16.55-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: Daniel Thompson <daniel.thompson@...aro.org>

commit c07d35338081d107e57cf37572d8cc931a8e32e2 upstream.

kallsyms_symbol_next() returns a boolean (true on success). Currently
kdb_read() tests the return value with an inequality that
unconditionally evaluates to true.

This is fixed in the obvious way and, since the conditional branch is
supposed to be unreachable, we also add a WARN_ON().

Reported-by: Dan Carpenter <dan.carpenter@...cle.com>
Signed-off-by: Daniel Thompson <daniel.thompson@...aro.org>
Signed-off-by: Jason Wessel <jason.wessel@...driver.com>
Signed-off-by: Ben Hutchings <ben@...adent.org.uk>
---
 kernel/debug/kdb/kdb_io.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/kernel/debug/kdb/kdb_io.c
+++ b/kernel/debug/kdb/kdb_io.c
@@ -349,7 +349,7 @@ poll_again:
 			}
 			kdb_printf("\n");
 			for (i = 0; i < count; i++) {
-				if (kallsyms_symbol_next(p_tmp, i) < 0)
+				if (WARN_ON(!kallsyms_symbol_next(p_tmp, i)))
 					break;
 				kdb_printf("%s ", p_tmp);
 				*(p_tmp + len) = '\0';