linux-kernel - [PATCH 3.16 086/114] tools lib traceevent: Do not reassign parg after collapse

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.1465842997.664244917@decadent.org.uk>
Date:	Mon, 13 Jun 2016 19:36:37 +0100
From:	Ben Hutchings <ben@...adent.org.uk>
To:	linux-kernel@...r.kernel.org, stable@...r.kernel.org
CC:	akpm@...ux-foundation.org, "Steven Rostedt" <rostedt@...dmis.org>,
	"Arnaldo Carvalho de Melo" <acme@...hat.com>,
	"Namhyung Kim" <namhyung@...nel.org>
Subject: [PATCH 3.16 086/114] tools lib traceevent: Do not reassign parg
 after collapse_tree()

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

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

From: Steven Rostedt <rostedt@...dmis.org>

commit 106b816cb46ebd87408b4ed99a2e16203114daa6 upstream.

At the end of process_filter(), collapse_tree() was changed to update
the parg parameter, but the reassignment after the call wasn't removed.

What happens is that the "current_op" gets modified and freed and parg
is assigned to the new allocated argument. But after the call to
collapse_tree(), parg is assigned again to the just freed "current_op",
and this causes the tool to crash.

The current_op variable must also be assigned to NULL in case of error,
otherwise it will cause it to be free()ed twice.

Signed-off-by: Steven Rostedt <rostedt@...dmis.org>
Acked-by: Namhyung Kim <namhyung@...nel.org>
Fixes: 42d6194d133c ("tools lib traceevent: Refactor process_filter()")
Link: http://lkml.kernel.org/r/20160511150936.678c18a1@gandalf.local.home
Signed-off-by: Arnaldo Carvalho de Melo <acme@...hat.com>
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings <ben@...adent.org.uk>
---
 tools/lib/traceevent/parse-filter.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/tools/lib/traceevent/parse-filter.c
+++ b/tools/lib/traceevent/parse-filter.c
@@ -1163,11 +1163,11 @@ process_filter(struct event_format *even
 		current_op = current_exp;
 
 	ret = collapse_tree(current_op, parg, error_str);
+	/* collapse_tree() may free current_op, and updates parg accordingly */
+	current_op = NULL;
 	if (ret < 0)
 		goto fail;
 
-	*parg = current_op;
-
 	return 0;
 
  fail_alloc: