Merge tag 'nfsd-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux

Pull nfsd updates from Chuck Lever:
 "Two significant security enhancements are part of this release:

   - NFSD's RPC header encoding and decoding, including RPCSEC GSS and
     gssproxy header parsing, has been overhauled to make it more
     memory-safe.

   - Support for Kerberos AES-SHA2-based encryption types has been added
     for both the NFS client and server. This provides a clean path for
     deprecating and removing insecure encryption types based on DES and
     SHA-1. AES-SHA2 is also FIPS-140 compliant, so that NFS with
     Kerberos may now be used on systems with fips enabled.

  In addition to these, NFSD is now able to handle crossing into an
  auto-mounted mount point on an exported NFS mount. A number of fixes
  have been made to NFSD's server-side copy implementation.

  RPC metrics have been converted to per-CPU variables. This helps
  reduce unnecessary cross-CPU and cross-node memory bus traffic, and
  significantly reduces noise when KCSAN is enabled"

* tag 'nfsd-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux: (121 commits)
  NFSD: Clean up nfsd_symlink()
  NFSD: copy the whole verifier in nfsd_copy_write_verifier
  nfsd: don't fsync nfsd_files on last close
  SUNRPC: Fix occasional warning when destroying gss_krb5_enctypes
  nfsd: fix courtesy client with deny mode handling in nfs4_upgrade_open
  NFSD: fix problems with cleanup on errors in nfsd4_copy
  nfsd: fix race to check ls_layouts
  nfsd: don't hand out delegation on setuid files being opened for write
  SUNRPC: Remove ->xpo_secure_port()
  SUNRPC: Clean up the svc_xprt_flags() macro
  nfsd: remove fs/nfsd/fault_inject.c
  NFSD: fix leaked reference count of nfsd4_ssc_umount_item
  nfsd: clean up potential nfsd_file refcount leaks in COPY codepath
  nfsd: zero out pointers after putting nfsd_files on COPY setup error
  SUNRPC: Fix whitespace damage in svcauth_unix.c
  nfsd: eliminate __nfs4_get_fd
  nfsd: add some kerneldoc comments for stateid preprocessing functions
  nfsd: eliminate find_deleg_file_locked
  nfsd: don't take nfsd4_copy ref for OP_OFFLOAD_STATUS
  SUNRPC: Add encryption self-tests
  ...

1 files changed, 123 insertions, 55 deletions

diff --git a/net/sunrpc/svcauth_unix.c b/net/sunrpc/svcauth_unix.c
index b1efc34db6ed..983c5891cb56 100644
--- a/net/sunrpc/svcauth_unix.c
+++ b/net/sunrpc/svcauth_unix.c
@@ -729,23 +729,38 @@ out:
 
 EXPORT_SYMBOL_GPL(svcauth_unix_set_client);
 
+/**
+ * svcauth_null_accept - Decode and validate incoming RPC_AUTH_NULL credential
+ * @rqstp: RPC transaction
+ *
+ * Return values:
+ *   %SVC_OK: Both credential and verifier are valid
+ *   %SVC_DENIED: Credential or verifier is not valid
+ *   %SVC_GARBAGE: Failed to decode credential or verifier
+ *   %SVC_CLOSE: Temporary failure
+ *
+ * rqstp->rq_auth_stat is set as mandated by RFC 5531.
+ */
 static int
 svcauth_null_accept(struct svc_rqst *rqstp)
 {
-	struct kvec	*argv = &rqstp->rq_arg.head[0];
-	struct kvec	*resv = &rqstp->rq_res.head[0];
+	struct xdr_stream *xdr = &rqstp->rq_arg_stream;
 	struct svc_cred	*cred = &rqstp->rq_cred;
+	u32 flavor, len;
+	void *body;
 
-	if (argv->iov_len < 3*4)
+	/* Length of Call's credential body field: */
+	if (xdr_stream_decode_u32(xdr, &len) < 0)
 		return SVC_GARBAGE;
-
-	if (svc_getu32(argv) != 0) {
-		dprintk("svc: bad null cred\n");
+	if (len != 0) {
 		rqstp->rq_auth_stat = rpc_autherr_badcred;
 		return SVC_DENIED;
 	}
-	if (svc_getu32(argv) != htonl(RPC_AUTH_NULL) || svc_getu32(argv) != 0) {
-		dprintk("svc: bad null verf\n");
+
+	/* Call's verf field: */
+	if (xdr_stream_decode_opaque_auth(xdr, &flavor, &body, &len) < 0)
+		return SVC_GARBAGE;
+	if (flavor != RPC_AUTH_NULL || len != 0) {
 		rqstp->rq_auth_stat = rpc_autherr_badverf;
 		return SVC_DENIED;
 	}
@@ -757,9 +772,11 @@ svcauth_null_accept(struct svc_rqst *rqstp)
 	if (cred->cr_group_info == NULL)
 		return SVC_CLOSE; /* kmalloc failure - client must retry */
 
-	/* Put NULL verifier */
-	svc_putnl(resv, RPC_AUTH_NULL);
-	svc_putnl(resv, 0);
+	if (xdr_stream_encode_opaque_auth(&rqstp->rq_res_stream,
+					  RPC_AUTH_NULL, NULL, 0) < 0)
+		return SVC_CLOSE;
+	if (!svcxdr_set_accept_stat(rqstp))
+		return SVC_CLOSE;
 
 	rqstp->rq_cred.cr_flavor = RPC_AUTH_NULL;
 	return SVC_OK;
@@ -783,31 +800,45 @@ struct auth_ops svcauth_null = {
 	.name		= "null",
 	.owner		= THIS_MODULE,
 	.flavour	= RPC_AUTH_NULL,
-	.accept 	= svcauth_null_accept,
+	.accept		= svcauth_null_accept,
 	.release	= svcauth_null_release,
 	.set_client	= svcauth_unix_set_client,
 };
 
 
+/**
+ * svcauth_tls_accept - Decode and validate incoming RPC_AUTH_TLS credential
+ * @rqstp: RPC transaction
+ *
+ * Return values:
+ *   %SVC_OK: Both credential and verifier are valid
+ *   %SVC_DENIED: Credential or verifier is not valid
+ *   %SVC_GARBAGE: Failed to decode credential or verifier
+ *   %SVC_CLOSE: Temporary failure
+ *
+ * rqstp->rq_auth_stat is set as mandated by RFC 5531.
+ */
 static int
 svcauth_tls_accept(struct svc_rqst *rqstp)
 {
+	struct xdr_stream *xdr = &rqstp->rq_arg_stream;
 	struct svc_cred	*cred = &rqstp->rq_cred;
-	struct kvec *argv = rqstp->rq_arg.head;
-	struct kvec *resv = rqstp->rq_res.head;
+	u32 flavor, len;
+	void *body;
+	__be32 *p;
 
-	if (argv->iov_len < XDR_UNIT * 3)
+	/* Length of Call's credential body field: */
+	if (xdr_stream_decode_u32(xdr, &len) < 0)
 		return SVC_GARBAGE;
-
-	/* Call's cred length */
-	if (svc_getu32(argv) != xdr_zero) {
+	if (len != 0) {
 		rqstp->rq_auth_stat = rpc_autherr_badcred;
 		return SVC_DENIED;
 	}
 
-	/* Call's verifier flavor and its length */
-	if (svc_getu32(argv) != rpc_auth_null ||
-	    svc_getu32(argv) != xdr_zero) {
+	/* Call's verf field: */
+	if (xdr_stream_decode_opaque_auth(xdr, &flavor, &body, &len) < 0)
+		return SVC_GARBAGE;
+	if (flavor != RPC_AUTH_NULL || len != 0) {
 		rqstp->rq_auth_stat = rpc_autherr_badverf;
 		return SVC_DENIED;
 	}
@@ -818,21 +849,27 @@ svcauth_tls_accept(struct svc_rqst *rqstp)
 		return SVC_DENIED;
 	}
 
-	/* Mapping to nobody uid/gid is required */
+	/* Signal that mapping to nobody uid/gid is required */
 	cred->cr_uid = INVALID_UID;
 	cred->cr_gid = INVALID_GID;
 	cred->cr_group_info = groups_alloc(0);
 	if (cred->cr_group_info == NULL)
-		return SVC_CLOSE; /* kmalloc failure - client must retry */
+		return SVC_CLOSE;
 
-	/* Reply's verifier */
-	svc_putnl(resv, RPC_AUTH_NULL);
 	if (rqstp->rq_xprt->xpt_ops->xpo_start_tls) {
-		svc_putnl(resv, 8);
-		memcpy(resv->iov_base + resv->iov_len, "STARTTLS", 8);
-		resv->iov_len += 8;
-	} else
-		svc_putnl(resv, 0);
+		p = xdr_reserve_space(&rqstp->rq_res_stream, XDR_UNIT * 2 + 8);
+		if (!p)
+			return SVC_CLOSE;
+		*p++ = rpc_auth_null;
+		*p++ = cpu_to_be32(8);
+		memcpy(p, "STARTTLS", 8);
+	} else {
+		if (xdr_stream_encode_opaque_auth(&rqstp->rq_res_stream,
+						  RPC_AUTH_NULL, NULL, 0) < 0)
+			return SVC_CLOSE;
+	}
+	if (!svcxdr_set_accept_stat(rqstp))
+		return SVC_CLOSE;
 
 	rqstp->rq_cred.cr_flavor = RPC_AUTH_TLS;
 	return SVC_OK;
@@ -842,32 +879,48 @@ struct auth_ops svcauth_tls = {
 	.name		= "tls",
 	.owner		= THIS_MODULE,
 	.flavour	= RPC_AUTH_TLS,
-	.accept 	= svcauth_tls_accept,
+	.accept		= svcauth_tls_accept,
 	.release	= svcauth_null_release,
 	.set_client	= svcauth_unix_set_client,
 };
 
 
+/**
+ * svcauth_unix_accept - Decode and validate incoming RPC_AUTH_SYS credential
+ * @rqstp: RPC transaction
+ *
+ * Return values:
+ *   %SVC_OK: Both credential and verifier are valid
+ *   %SVC_DENIED: Credential or verifier is not valid
+ *   %SVC_GARBAGE: Failed to decode credential or verifier
+ *   %SVC_CLOSE: Temporary failure
+ *
+ * rqstp->rq_auth_stat is set as mandated by RFC 5531.
+ */
 static int
 svcauth_unix_accept(struct svc_rqst *rqstp)
 {
-	struct kvec	*argv = &rqstp->rq_arg.head[0];
-	struct kvec	*resv = &rqstp->rq_res.head[0];
+	struct xdr_stream *xdr = &rqstp->rq_arg_stream;
 	struct svc_cred	*cred = &rqstp->rq_cred;
 	struct user_namespace *userns;
-	u32		slen, i;
-	int		len   = argv->iov_len;
+	u32 flavor, len, i;
+	void *body;
+	__be32 *p;
 
-	if ((len -= 3*4) < 0)
+	/*
+	 * This implementation ignores the length of the Call's
+	 * credential body field and the timestamp and machinename
+	 * fields.
+	 */
+	p = xdr_inline_decode(xdr, XDR_UNIT * 3);
+	if (!p)
+		return SVC_GARBAGE;
+	len = be32_to_cpup(p + 2);
+	if (len > RPC_MAX_MACHINENAME)
+		return SVC_GARBAGE;
+	if (!xdr_inline_decode(xdr, len))
 		return SVC_GARBAGE;
 
-	svc_getu32(argv);			/* length */
-	svc_getu32(argv);			/* time stamp */
-	slen = XDR_QUADLEN(svc_getnl(argv));	/* machname length */
-	if (slen > 64 || (len -= (slen + 3)*4) < 0)
-		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.
@@ -877,27 +930,42 @@ svcauth_unix_accept(struct svc_rqst *rqstp)
 	 */
 	userns = (rqstp->rq_xprt && rqstp->rq_xprt->xpt_cred) ?
 		rqstp->rq_xprt->xpt_cred->user_ns : &init_user_ns;
-	cred->cr_uid = make_kuid(userns, svc_getnl(argv)); /* uid */
-	cred->cr_gid = make_kgid(userns, svc_getnl(argv)); /* gid */
-	slen = svc_getnl(argv);			/* gids length */
-	if (slen > UNX_NGROUPS || (len -= (slen + 2)*4) < 0)
+	if (xdr_stream_decode_u32(xdr, &i) < 0)
+		return SVC_GARBAGE;
+	cred->cr_uid = make_kuid(userns, i);
+	if (xdr_stream_decode_u32(xdr, &i) < 0)
+		return SVC_GARBAGE;
+	cred->cr_gid = make_kgid(userns, i);
+
+	if (xdr_stream_decode_u32(xdr, &len) < 0)
+		return SVC_GARBAGE;
+	if (len > UNX_NGROUPS)
 		goto badcred;
-	cred->cr_group_info = groups_alloc(slen);
+	p = xdr_inline_decode(xdr, XDR_UNIT * len);
+	if (!p)
+		return SVC_GARBAGE;
+	cred->cr_group_info = groups_alloc(len);
 	if (cred->cr_group_info == NULL)
 		return SVC_CLOSE;
-	for (i = 0; i < slen; i++) {
-		kgid_t kgid = make_kgid(userns, svc_getnl(argv));
+	for (i = 0; i < len; i++) {
+		kgid_t kgid = make_kgid(userns, be32_to_cpup(p++));
 		cred->cr_group_info->gid[i] = kgid;
 	}
 	groups_sort(cred->cr_group_info);
-	if (svc_getu32(argv) != htonl(RPC_AUTH_NULL) || svc_getu32(argv) != 0) {
+
+	/* Call's verf field: */
+	if (xdr_stream_decode_opaque_auth(xdr, &flavor, &body, &len) < 0)
+		return SVC_GARBAGE;
+	if (flavor != RPC_AUTH_NULL || len != 0) {
 		rqstp->rq_auth_stat = rpc_autherr_badverf;
 		return SVC_DENIED;
 	}
 
-	/* Put NULL verifier */
-	svc_putnl(resv, RPC_AUTH_NULL);
-	svc_putnl(resv, 0);
+	if (xdr_stream_encode_opaque_auth(&rqstp->rq_res_stream,
+					  RPC_AUTH_NULL, NULL, 0) < 0)
+		return SVC_CLOSE;
+	if (!svcxdr_set_accept_stat(rqstp))
+		return SVC_CLOSE;
 
 	rqstp->rq_cred.cr_flavor = RPC_AUTH_UNIX;
 	return SVC_OK;
@@ -927,7 +995,7 @@ struct auth_ops svcauth_unix = {
 	.name		= "unix",
 	.owner		= THIS_MODULE,
 	.flavour	= RPC_AUTH_UNIX,
-	.accept 	= svcauth_unix_accept,
+	.accept		= svcauth_unix_accept,
 	.release	= svcauth_unix_release,
 	.domain_release	= svcauth_unix_domain_release,
 	.set_client	= svcauth_unix_set_client,