[PATCH 5.11 132/329] nfs: Subsequent READDIR calls should carry non-zero cookieverifier

From: Greg Kroah-Hartman
Date: Mon May 17 2021 - 11:10:01 EST


From: Nagendra S Tomar <natomar@xxxxxxxxxxxxx>

[ Upstream commit ee3707ae2c1f1327ad5188836b7ab62ed2c93b28 ]

If the loop in nfs_readdir_xdr_to_array() runs more than once, subsequent
READDIR RPCs may wrongly carry a zero cookie verifier and non-zero cookie.
Make sure subsequent calls to READDIR carry the cookie verifier returned
by the first call.

Signed-off-by: Nagendra S Tomar <natomar@xxxxxxxxxxxxx>
Fixes: b593c09f83a2 ("NFS: Improve handling of directory verifiers")
Signed-off-by: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
fs/nfs/dir.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index 4db3018776f6..c3618b6abfc0 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -865,6 +865,8 @@ static int nfs_readdir_xdr_to_array(struct nfs_readdir_descriptor *desc,
break;
}

+ verf_arg = verf_res;
+
status = nfs_readdir_page_filler(desc, entry, pages, pglen,
arrays, narrays);
} while (!status && nfs_readdir_page_needs_filling(page));
--
2.30.2