[PATCH v2 2/2] NFSD: WARN if fi_fds[O_RDONLY] is already populated

[Chuck Lever <cel@kernel.org>]

From: Chuck Lever <chuck.lever@oracle.com>

nfsd4_add_rdaccess_to_wrdeleg() expects that fi_fds[O_RDONLY] is
NULL. If it's not NULL, there's a software bug somewhere else that
needs to be looked into.

Replace the redundant fp assignment with a WARN_ON_ONCE.

Suggested-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
 fs/nfsd/nfs4state.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 1c9802d06de1..b8fd0ed3fd53 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -6236,7 +6236,7 @@ nfsd4_add_rdaccess_to_wrdeleg(struct svc_rqst *rqstp, struct nfsd4_open *open,
 		fp = stp->st_stid.sc_file;
 		spin_lock(&fp->fi_lock);
 		__nfs4_file_get_access(fp, NFS4_SHARE_ACCESS_READ);
-		fp = stp->st_stid.sc_file;
+		WARN_ON_ONCE(fp->fi_fds[O_RDONLY] != NULL);
 		fp->fi_fds[O_RDONLY] = nf;
 		fp->fi_rdeleg_file = nf;
 		spin_unlock(&fp->fi_lock);
-- 
2.52.0