Ocfs2 devel - Jun 2011 - [PATCH 1/1] ocfs2: Add readonly check in ocfs2_quota_on().

Enabling quota on a readonly ocfs2 fs caused a 'NULL pointer
dereference' in
dquot_enable(), a very straightforward fix is to check readonly at the very
beginning of ocfs2_quota_on(), which calls dquot_enable().

Signed-off-by: Tristan Ye <tristan.ye at oracle.com>
---
 fs/ocfs2/super.c |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/fs/ocfs2/super.c b/fs/ocfs2/super.c
index 029c4cd..3cade2a 100644
--- a/fs/ocfs2/super.c
+++ b/fs/ocfs2/super.c
@@ -995,6 +995,10 @@ static int ocfs2_quota_on(struct super_block *sb, int type,
int format_id)
 	if (!OCFS2_HAS_RO_COMPAT_FEATURE(sb, feature[type]))
 		return -EINVAL;
 
+	if (ocfs2_is_hard_readonly(OCFS2_SB(sb))) {
+		return -EROFS;
+	}
+
 	return dquot_enable(sb_dqopt(sb)->files[type], type,
 			    format_id, DQUOT_LIMITS_ENABLED);
 }
-- 
1.5.5

Enabling quota on a readonly ocfs2 fs caused a 'NULL pointer
dereference' in
dquot_enable(), a very straightforward fix is to check readonly at the very
beginning of ocfs2_quota_on(), which calls dquot_enable().

Signed-off-by: Tristan Ye <tristan.ye at oracle.com>
---
 fs/ocfs2/super.c |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/fs/ocfs2/super.c b/fs/ocfs2/super.c
index 029c4cd..3cade2a 100644
--- a/fs/ocfs2/super.c
+++ b/fs/ocfs2/super.c
@@ -995,6 +995,10 @@ static int ocfs2_quota_on(struct super_block *sb, int type,
int format_id)
 	if (!OCFS2_HAS_RO_COMPAT_FEATURE(sb, feature[type]))
 		return -EINVAL;
 
+	if (ocfs2_is_hard_readonly(OCFS2_SB(sb))) {
+		return -EROFS;
+	}
+
 	return dquot_enable(sb_dqopt(sb)->files[type], type,
 			    format_id, DQUOT_LIMITS_ENABLED);
 }
-- 
1.5.5