linux-kernel - [PATCH 1/2] memcg: mm_update_next

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]

Date:	Fri, 18 Apr 2014 19:26:53 +0200
From:	Oleg Nesterov <oleg@...hat.com>
To:	Andrew Morton <akpm@...ux-foundation.org>,
	Peter Chiang <pchiang@...dia.com>,
	KAMEZAWA Hiroyuki <kamezawa.hiroyu@...fujitsu.com>,
	Balbir Singh <bsingharora@...il.com>,
	Michal Hocko <mhocko@...e.cz>,
	Johannes Weiner <hannes@...xchg.org>
Cc:	"ccross@...roid.com" <ccross@...roid.com>,
	"lizefan@...wei.com" <lizefan@...wei.com>,
	"tj@...nel.org" <tj@...nel.org>, "pavel@....cz" <pavel@....cz>,
	"ebiederm@...ssion.com" <ebiederm@...ssion.com>,
	"guillaume@...infr.org" <guillaume@...infr.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: [PATCH 1/2] memcg: mm_update_next_owner() should skip kthreads

"Search through everything else" in mm_update_next_owner() can
hit a kthread which adopted this "mm" via use_mm(), it should
not be used as mm->owner. Add the PF_KTHREAD check.

While at it, change this code to use for_each_process_thread()
instead of deprecated do_each_thread/while_each_thread.

Signed-off-by: Oleg Nesterov <oleg@...hat.com>
---
 kernel/exit.c |   10 ++++------
 1 files changed, 4 insertions(+), 6 deletions(-)

diff --git a/kernel/exit.c b/kernel/exit.c
index ad7183a..e270d2a 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -356,14 +356,12 @@ retry:
 	}
 
 	/*
-	 * Search through everything else. We should not get
-	 * here often
+	 * Search through everything else, we should not get here often.
 	 */
-	do_each_thread(g, c) {
-		if (c->mm == mm)
+	for_each_process_thread(g, c) {
+		if (!(c->flags & PF_KTHREAD) && c->mm == mm)
 			goto assign_new_owner;
-	} while_each_thread(g, c);
-
+	}
 	read_unlock(&tasklist_lock);
 	/*
 	 * We found no owner yet mm_users > 1: this implies that we are
-- 
1.5.5.1


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/