5.4-stable review patch. If anyone has any objections, please let me know.
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From: Trond Myklebust trond.myklebust@hammerspace.com
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@hammerspace.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- 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)