From: Trond Myklebust <trondmy@gmail.com>
Date: Sun, 26 Jan 2020 17:31:13 -0500
Subject: [PATCH] NFSv4: pnfs_roc() must use cred_fscmp() to compare creds
Git-commit: 387122478775be5d9816c34aa29de53d0b926835
Patch-mainline: v5.6-rc1
References: git-fixes

When comparing two 'struct cred' for equality w.r.t. behaviour under
filesystem access, we need to use cred_fscmp().

Fixes: a52458b48af1 ("NFS/NFSD/SUNRPC: replace generic creds with 'struct cred'.")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Acked-by: NeilBrown <neilb@suse.com>

---
 fs/nfs/pnfs.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/fs/nfs/pnfs.c
+++ b/fs/nfs/pnfs.c
@@ -1415,7 +1415,7 @@ retry:
 	/* lo ref dropped in pnfs_roc_release() */
 	layoutreturn = pnfs_prepare_layoutreturn(lo, &stateid, &iomode);
 	/* If the creds don't match, we can't compound the layoutreturn */
-	if (!layoutreturn || cred != lo->plh_lc_cred)
+	if (!layoutreturn || cred_fscmp(cred, lo->plh_lc_cred) != 0)
 		goto out_noroc;
 
 	roc = layoutreturn;