From: Toshiyuki Okajima <toshi.okajima@jp.fujitsu.com>
To: Gao feng <gaofeng@cn.fujitsu.com>, <viro@zeniv.linux.org.uk>,
<eparis@redhat.com>
Cc: <toshi.okajima@jp.fujitsu.com>, <linux-kernel@vger.kernel.org>
Subject: [BUG][PATCH] audit: audit_log_start running on auditd should not stop
Date: Tue, 15 Oct 2013 13:43:45 +0900 [thread overview]
Message-ID: <20131015134345.98d72df42a39e9e1ad77a73c@jp.fujitsu.com> (raw)
In-Reply-To: <5257EF15.6080209@jp.fujitsu.com>
The backlog cannot be consumed when audit_log_start is running on auditd
even if audit_log_start calls wait_for_auditd to consume it.
The situation is a deadlock because only auditd can consume the backlog.
If the other process needs to send the backlog, it can be also stopped
by the deadlock.
So, audit_log_start running on auditd should not stop.
You can see the deadlock with the following reproducer:
# auditctl -a exit,always -S all
# reboot
Signed-off-by: Toshiyuki Okajima <toshi.okajima@jp.fujitsu.com>
Cc: gaofeng@cn.fujitsu.com
---
kernel/audit.c | 3 +++
1 files changed, 3 insertions(+), 0 deletions(-)
diff --git a/kernel/audit.c b/kernel/audit.c
index 7b0e23a..ce1fb38 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -1098,6 +1098,9 @@ struct audit_buffer *audit_log_start(struct audit_context *ctx, gfp_t gfp_mask,
int reserve;
unsigned long timeout_start = jiffies;
+ if (audit_pid && audit_pid == current->pid)
+ gfp_mask &= ~__GFP_WAIT;
+
if (audit_initialized != AUDIT_INITIALIZED)
return NULL;
--
1.5.5.6
next prev parent reply other threads:[~2013-10-15 4:43 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-10-11 1:36 [BUG][PATCH][RFC] audit: hang up in audit_log_start executed on auditd Toshiyuki Okajima
2013-10-11 9:33 ` Gao feng
2013-10-11 12:29 ` Toshiyuki Okajima (smtp-b.css)
2013-10-15 4:43 ` Toshiyuki Okajima [this message]
2013-10-15 6:30 ` [BUG][PATCH] audit: audit_log_start running on auditd should not stop Gao feng
2013-10-15 7:07 ` Toshiyuki Okajima
2013-10-15 7:58 ` [BUG][PATCH V3] " Toshiyuki Okajima
2013-10-15 9:41 ` Gao feng
2013-10-23 19:55 ` [BUG][PATCH] " Richard Guy Briggs
2013-10-24 5:55 ` Gao feng
2013-10-24 19:35 ` Richard Guy Briggs
2013-10-25 1:36 ` Toshiyuki Okajima
2013-10-25 15:12 ` Eric Paris
2013-10-28 9:20 ` Toshiyuki Okajima
2013-12-05 2:45 ` [PATCH 0/3] audit: remove audit_log_start() contention in AUDIT_USER type calls Richard Guy Briggs
2013-12-05 2:45 ` [PATCH 1/3] selinux: call WARN_ONCE() instead of calling audit_log_start() Richard Guy Briggs
2013-12-05 2:45 ` [PATCH 2/3] smack: " Richard Guy Briggs
2013-12-06 18:40 ` Casey Schaufler
2013-12-08 22:17 ` Richard Guy Briggs
2013-12-05 2:45 ` [PATCH 3/3] audit: drop audit_cmd_lock in AUDIT_USER family of cases Richard Guy Briggs
2013-12-09 2:31 ` Toshiyuki Okajima
2013-12-05 7:15 ` [RESEND][BUG][PATCH V3] audit: audit_log_start running on auditd should not stop Toshiyuki Okajima
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20131015134345.98d72df42a39e9e1ad77a73c@jp.fujitsu.com \
--to=toshi.okajima@jp.fujitsu.com \
--cc=eparis@redhat.com \
--cc=gaofeng@cn.fujitsu.com \
--cc=linux-kernel@vger.kernel.org \
--cc=viro@zeniv.linux.org.uk \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).