[GFS2] possible null pointer dereference fixup

gfs2_alloc_get may fail so we have to check it to prevent
NULL pointer dereference.

Signed-off-by: Cyrill Gorcunov <gorcunov@gamil.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

1 files changed, 10 insertions, 1 deletions

diff --git a/fs/gfs2/ops_inode.c b/fs/gfs2/ops_inode.c
index 6cbbb5b46ce4..34fe571e15ee 100644
--- a/fs/gfs2/ops_inode.c
+++ b/fs/gfs2/ops_inode.c
@@ -200,6 +200,10 @@ static int gfs2_link(struct dentry *old_dentry, struct inode *dir,
 
         if (alloc_required) {
                 struct gfs2_alloc *al = gfs2_alloc_get(dip);
+                if (!al) {
+                        error = -ENOMEM;
+                        goto out_gunlock;
+                }
 
                 error = gfs2_quota_lock(dip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE);
                 if (error)
@@ -716,6 +720,10 @@ static int gfs2_rename(struct inode *odir, struct dentry *odentry,
 
         if (alloc_required) {
                 struct gfs2_alloc *al = gfs2_alloc_get(ndip);
+                if (!al) {
+                        error = -ENOMEM;
+                        goto out_gunlock;
+                }
 
                 error = gfs2_quota_lock(ndip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE);
                 if (error)
@@ -953,7 +961,8 @@ static int setattr_chown(struct inode *inode, struct iattr *attr)
         if (!(attr->ia_valid & ATTR_GID) || ogid == ngid)
                 ogid = ngid = NO_QUOTA_CHANGE;
 
-        gfs2_alloc_get(ip);
+        if (!gfs2_alloc_get(ip))
+                return -ENOMEM;
 
         error = gfs2_quota_lock(ip, nuid, ngid);
         if (error)