svcrpc: fix failures to handle -1 uid's and gid's
As of f025adf191924e3a75ce80e130afcd2485b53bb8 "sunrpc: Properly decode
kuids and kgids in RPC_AUTH_UNIX credentials" any rpc containing a -1
(0xffff) uid or gid would fail with a badcred error.
Reported symptoms were xmbc clients failing on upgrade of the NFS
server; examination of the network trace showed them sending -1 as the
gid.
Reported-by: Julian Sikorski <belegdol@gmail.com>
Tested-by: Julian Sikorski <belegdol@gmail.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
diff --git a/net/sunrpc/svcauth_unix.c b/net/sunrpc/svcauth_unix.c
index c3f9e1e..06bdf5a 100644
--- a/net/sunrpc/svcauth_unix.c
+++ b/net/sunrpc/svcauth_unix.c
@@ -810,11 +810,15 @@
goto badcred;
argv->iov_base = (void*)((__be32*)argv->iov_base + slen); /* skip machname */
argv->iov_len -= slen*4;
-
+ /*
+ * Note: we skip uid_valid()/gid_valid() checks here for
+ * backwards compatibility with clients that use -1 id's.
+ * Instead, -1 uid or gid is later mapped to the
+ * (export-specific) anonymous id by nfsd_setuser.
+ * Supplementary gid's will be left alone.
+ */
cred->cr_uid = make_kuid(&init_user_ns, svc_getnl(argv)); /* uid */
cred->cr_gid = make_kgid(&init_user_ns, svc_getnl(argv)); /* gid */
- if (!uid_valid(cred->cr_uid) || !gid_valid(cred->cr_gid))
- goto badcred;
slen = svc_getnl(argv); /* gids length */
if (slen > 16 || (len -= (slen + 2)*4) < 0)
goto badcred;
@@ -823,8 +827,6 @@
return SVC_CLOSE;
for (i = 0; i < slen; i++) {
kgid_t kgid = make_kgid(&init_user_ns, svc_getnl(argv));
- if (!gid_valid(kgid))
- goto badcred;
GROUP_AT(cred->cr_group_info, i) = kgid;
}
if (svc_getu32(argv) != htonl(RPC_AUTH_NULL) || svc_getu32(argv) != 0) {