staging/lustre/llite: protect from accessing NULL lli_clob

Need to check file's lli_clob object before calling
lov_read_and_clear_async_rc().

Signed-off-by: Bobi Jam <bobijam.xu@intel.com>
Reviewed-by: Jinshan Xiong <jinshan.xiong@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>
Reviewed-on: http://review.whamcloud.com/23031
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-8682
Signed-off-by: Oleg Drokin <green@linuxhacker.ru>
Reviewed-by: James Simmons <jsimmons@infradead.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/lustre/lustre/llite/file.c b/drivers/staging/lustre/lustre/llite/file.c
index c1c7551..7886840 100644 (file)
--- a/drivers/staging/lustre/lustre/llite/file.c
+++ b/drivers/staging/lustre/lustre/llite/file.c
@@ -2328,9 +2328,11 @@ int ll_fsync(struct file *file, loff_t start, loff_t end, int datasync)
                lli->lli_async_rc = 0;
                if (rc == 0)
                        rc = err;
-               err = lov_read_and_clear_async_rc(lli->lli_clob);
-               if (rc == 0)
-                       rc = err;
+               if (lli->lli_clob) {
+                       err = lov_read_and_clear_async_rc(lli->lli_clob);
+                       if (rc == 0)
+                               rc = err;
+               }
        }
 
        err = md_sync(ll_i2sbi(inode)->ll_md_exp, ll_inode2fid(inode), &req);