1 files changed, 14 insertions, 4 deletions

diff --git a/fs/ceph/export.c b/fs/ceph/export.c
index 8e1b60e557b6..02ce90972d81 100644
--- a/fs/ceph/export.c
+++ b/fs/ceph/export.c
@@ -99,7 +99,7 @@ static int ceph_encode_fh(struct inode *inode, u32 *rawfh, int *max_len,
  * FIXME: we should try harder by querying the mds for the ino.
  */
 static struct dentry *__fh_to_dentry(struct super_block *sb,
-                                     struct ceph_nfs_fh *fh)
+                                     struct ceph_nfs_fh *fh, int fh_len)
 {
         struct ceph_mds_client *mdsc = ceph_sb_to_client(sb)->mdsc;
         struct inode *inode;
@@ -107,6 +107,9 @@ static struct dentry *__fh_to_dentry(struct super_block *sb,
         struct ceph_vino vino;
         int err;
 
+        if (fh_len < sizeof(*fh) / 4)
+                return ERR_PTR(-ESTALE);
+
         dout("__fh_to_dentry %llx\n", fh->ino);
         vino.ino = fh->ino;
         vino.snap = CEPH_NOSNAP;
@@ -150,7 +153,7 @@ static struct dentry *__fh_to_dentry(struct super_block *sb,
  * convert connectable fh to dentry
  */
 static struct dentry *__cfh_to_dentry(struct super_block *sb,
-                                      struct ceph_nfs_confh *cfh)
+                                      struct ceph_nfs_confh *cfh, int fh_len)
 {
         struct ceph_mds_client *mdsc = ceph_sb_to_client(sb)->mdsc;
         struct inode *inode;
@@ -158,6 +161,9 @@ static struct dentry *__cfh_to_dentry(struct super_block *sb,
         struct ceph_vino vino;
         int err;
 
+        if (fh_len < sizeof(*cfh) / 4)
+                return ERR_PTR(-ESTALE);
+
         dout("__cfh_to_dentry %llx (%llx/%x)\n",
              cfh->ino, cfh->parent_ino, cfh->parent_name_hash);
 
@@ -207,9 +213,11 @@ static struct dentry *ceph_fh_to_dentry(struct super_block *sb, struct fid *fid,
                                         int fh_len, int fh_type)
 {
         if (fh_type == 1)
-                return __fh_to_dentry(sb, (struct ceph_nfs_fh *)fid->raw);
+                return __fh_to_dentry(sb, (struct ceph_nfs_fh *)fid->raw,
+                                                                fh_len);
         else
-                return __cfh_to_dentry(sb, (struct ceph_nfs_confh *)fid->raw);
+                return __cfh_to_dentry(sb, (struct ceph_nfs_confh *)fid->raw,
+                                                                fh_len);
 }
 
 /*
@@ -230,6 +238,8 @@ static struct dentry *ceph_fh_to_parent(struct super_block *sb,
 
         if (fh_type == 1)
                 return ERR_PTR(-ESTALE);
+        if (fh_len < sizeof(*cfh) / 4)
+                return ERR_PTR(-ESTALE);
 
         pr_debug("fh_to_parent %llx/%d\n", cfh->parent_ino,
                  cfh->parent_name_hash);