linux-ext4 - [PATCH 1/3 v2] quota: protect Q_GETFMT by dqonoff

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:	Wed, 28 May 2014 09:52:19 +0800
From:	Niu Yawei <yawei.niu@...il.com>
To:	Christoph Hellwig <hch@...radead.org>, jack@...e.cz
CC:	linux-fsdevel@...r.kernel.org, linux-ext4@...r.kernel.org,
	yawei.niu@...el.com, andreas.dilger@...el.com, lai.siyao@...el.com
Subject: [PATCH 1/3 v2] quota: protect Q_GETFMT by dqonoff_mutex

Remove dqptr_sem to make quota code scalable: Protect the
Q_GETFMT by dqonoff_mutex instead of dqptr_sem.

Signed-off-by: Lai Siyao <lai.siyao@...el.com>
Signed-off-by: Niu Yawei <yawei.niu@...el.com>
---
 fs/quota/quota.c |    6 +++---
 1 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/fs/quota/quota.c b/fs/quota/quota.c
index 2b363e2..e4851cb 100644
--- a/fs/quota/quota.c
+++ b/fs/quota/quota.c
@@ -79,13 +79,13 @@ static int quota_getfmt(struct super_block *sb, int type, void __user *addr)
 {
 	__u32 fmt;
 
-	down_read(&sb_dqopt(sb)->dqptr_sem);
+	mutex_lock(&sb_dqopt(sb)->dqonoff_mutex);
 	if (!sb_has_quota_active(sb, type)) {
-		up_read(&sb_dqopt(sb)->dqptr_sem);
+		mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex);
 		return -ESRCH;
 	}
 	fmt = sb_dqopt(sb)->info[type].dqi_format->qf_fmt_id;
-	up_read(&sb_dqopt(sb)->dqptr_sem);
+	mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex);
 	if (copy_to_user(addr, &fmt, sizeof(fmt)))
 		return -EFAULT;
 	return 0;
-- 
1.7.1


--
To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html