5.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
commit 9c07b75b80eeff714420fb6a4c880b284e529d0f upstream.
The struct nfs_server gets put on the cl_superblocks list before
the server->super field has been initialised, in which case the
call to nfs_sb_active() will Oops. Add a check to ensure that
we skip such a list entry.
Fixes: 3c9e502b59fb ("NFS: Add a helper nfs_client_for_each_server()")
Signed-off-by: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/nfs/super.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -445,7 +445,7 @@ static int __nfs_list_for_each_server(st
rcu_read_lock();
list_for_each_entry_rcu(server, head, client_link) {
- if (!nfs_sb_active(server->super))
+ if (!(server->super && nfs_sb_active(server->super)))
continue;
rcu_read_unlock();
if (last)
