nfsd4: session needs room for following op to error out

commit 4c69d5855a16f7378648c5733632628fa10431db upstream.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>

diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
index 419572f33b72dafaf04a770fb53e29e250e5f42b..622ede143585109e32f00cedf09eb4195599bd32 100644 (file)
--- a/fs/nfsd/nfs4proc.c
+++ b/fs/nfsd/nfs4proc.c
@@ -1349,6 +1349,12 @@ nfsd4_proc_compound(struct svc_rqst *rqstp,
                /* If op is non-idempotent */
                if (opdesc->op_flags & OP_MODIFIES_SOMETHING) {
                        plen = opdesc->op_rsize_bop(rqstp, op);
+                       /*
+                        * If there's still another operation, make sure
+                        * we'll have space to at least encode an error:
+                        */
+                       if (resp->opcnt < args->opcnt)
+                               plen += COMPOUND_ERR_SLACK_SPACE;
                        op->status = nfsd4_check_resp_size(resp, plen);
                }