nfsd: return better errors to exportfs
Someone noticed exportfs happily accepted exports that would later be
rejected when mountd tried to give them to the kernel. Fix this.
This is a regression from 4c1e1b34d5c800ad3ac9a7e2805b0bea70ad2278
"nfsd: Store ex_anon_uid and ex_anon_gid as kuids and kgids".
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: stable@vger.kernel.org
Reported-by: Yin.JianHong <jiyin@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
diff --git a/fs/nfsd/export.c b/fs/nfsd/export.c
index 5f38ea3..af51cf9 100644
--- a/fs/nfsd/export.c
+++ b/fs/nfsd/export.c
@@ -536,16 +536,12 @@
if (err)
goto out3;
exp.ex_anon_uid= make_kuid(&init_user_ns, an_int);
- if (!uid_valid(exp.ex_anon_uid))
- goto out3;
/* anon gid */
err = get_int(&mesg, &an_int);
if (err)
goto out3;
exp.ex_anon_gid= make_kgid(&init_user_ns, an_int);
- if (!gid_valid(exp.ex_anon_gid))
- goto out3;
/* fsid */
err = get_int(&mesg, &an_int);
@@ -583,6 +579,17 @@
exp.ex_uuid);
if (err)
goto out4;
+ /*
+ * For some reason exportfs has been passing down an
+ * invalid (-1) uid & gid on the "dummy" export which it
+ * uses to test export support. To make sure exportfs
+ * sees errors from check_export we therefore need to
+ * delay these checks till after check_export:
+ */
+ if (!uid_valid(exp.ex_anon_uid))
+ goto out4;
+ if (!gid_valid(exp.ex_anon_gid))
+ goto out4;
}
expp = svc_export_lookup(&exp);
