1 files changed, 121 insertions, 125 deletions

diff --git a/net/sunrpc/auth_unix.c b/net/sunrpc/auth_unix.c
index dc37021fc3e5..1e091d3fa607 100644
--- a/net/sunrpc/auth_unix.c
+++ b/net/sunrpc/auth_unix.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * linux/net/sunrpc/auth_unix.c
  *
@@ -10,96 +11,60 @@
 #include <linux/types.h>
 #include <linux/sched.h>
 #include <linux/module.h>
+#include <linux/mempool.h>
 #include <linux/sunrpc/clnt.h>
 #include <linux/sunrpc/auth.h>
 #include <linux/user_namespace.h>
 
-#define NFS_NGROUPS	16
 
-struct unx_cred {
-	struct rpc_cred		uc_base;
-	kgid_t			uc_gid;
-	kgid_t			uc_gids[NFS_NGROUPS];
-};
-#define uc_uid			uc_base.cr_uid
-
-#define UNX_WRITESLACK		(21 + (UNX_MAXNODENAME >> 2))
-
-#ifdef RPC_DEBUG
+#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
 # define RPCDBG_FACILITY	RPCDBG_AUTH
 #endif
 
 static struct rpc_auth		unix_auth;
 static const struct rpc_credops	unix_credops;
+static mempool_t		*unix_pool;
 
 static struct rpc_auth *
-unx_create(struct rpc_clnt *clnt, rpc_authflavor_t flavor)
+unx_create(const struct rpc_auth_create_args *args, struct rpc_clnt *clnt)
 {
-	dprintk("RPC:       creating UNIX authenticator for client %p\n",
-			clnt);
-	atomic_inc(&unix_auth.au_count);
+	refcount_inc(&unix_auth.au_count);
 	return &unix_auth;
 }
 
 static void
 unx_destroy(struct rpc_auth *auth)
 {
-	dprintk("RPC:       destroying UNIX authenticator %p\n", auth);
-	rpcauth_clear_credcache(auth->au_credcache);
 }
 
 /*
  * Lookup AUTH_UNIX creds for current process
  */
-static struct rpc_cred *
-unx_lookup_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags)
+static struct rpc_cred *unx_lookup_cred(struct rpc_auth *auth,
+					struct auth_cred *acred, int flags)
 {
-	return rpcauth_lookup_credcache(auth, acred, flags);
-}
-
-static struct rpc_cred *
-unx_create_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags)
-{
-	struct unx_cred	*cred;
-	unsigned int groups = 0;
-	unsigned int i;
-
-	dprintk("RPC:       allocating UNIX cred for uid %d gid %d\n",
-			from_kuid(&init_user_ns, acred->uid),
-			from_kgid(&init_user_ns, acred->gid));
-
-	if (!(cred = kmalloc(sizeof(*cred), GFP_NOFS)))
-		return ERR_PTR(-ENOMEM);
-
-	rpcauth_init_cred(&cred->uc_base, acred, auth, &unix_credops);
-	cred->uc_base.cr_flags = 1UL << RPCAUTH_CRED_UPTODATE;
-
-	if (acred->group_info != NULL)
-		groups = acred->group_info->ngroups;
-	if (groups > NFS_NGROUPS)
-		groups = NFS_NGROUPS;
-
-	cred->uc_gid = acred->gid;
-	for (i = 0; i < groups; i++)
-		cred->uc_gids[i] = GROUP_AT(acred->group_info, i);
-	if (i < NFS_NGROUPS)
-		cred->uc_gids[i] = INVALID_GID;
-
-	return &cred->uc_base;
-}
-
-static void
-unx_free_cred(struct unx_cred *unx_cred)
-{
-	dprintk("RPC:       unx_free_cred %p\n", unx_cred);
-	kfree(unx_cred);
+	struct rpc_cred *ret;
+
+	ret = kmalloc(sizeof(*ret), rpc_task_gfp_mask());
+	if (!ret) {
+		if (!(flags & RPCAUTH_LOOKUP_ASYNC))
+			return ERR_PTR(-ENOMEM);
+		ret = mempool_alloc(unix_pool, GFP_NOWAIT);
+		if (!ret)
+			return ERR_PTR(-ENOMEM);
+	}
+	rpcauth_init_cred(ret, acred, auth, &unix_credops);
+	ret->cr_flags = 1UL << RPCAUTH_CRED_UPTODATE;
+	return ret;
 }
 
 static void
 unx_free_cred_callback(struct rcu_head *head)
 {
-	struct unx_cred *unx_cred = container_of(head, struct unx_cred, uc_base.cr_rcu);
-	unx_free_cred(unx_cred);
+	struct rpc_cred *rpc_cred = container_of(head, struct rpc_cred, cr_rcu);
+
+	put_cred(rpc_cred->cr_cred);
+	mempool_free(rpc_cred, unix_pool);
 }
 
 static void
@@ -109,30 +74,32 @@ unx_destroy_cred(struct rpc_cred *cred)
 }
 
 /*
- * Match credentials against current process creds.
- * The root_override argument takes care of cases where the caller may
- * request root creds (e.g. for NFS swapping).
+ * Match credentials against current the auth_cred.
  */
 static int
-unx_match(struct auth_cred *acred, struct rpc_cred *rcred, int flags)
+unx_match(struct auth_cred *acred, struct rpc_cred *cred, int flags)
 {
-	struct unx_cred	*cred = container_of(rcred, struct unx_cred, uc_base);
 	unsigned int groups = 0;
 	unsigned int i;
 
+	if (cred->cr_cred == acred->cred)
+		return 1;
+
+	if (!uid_eq(cred->cr_cred->fsuid, acred->cred->fsuid) || !gid_eq(cred->cr_cred->fsgid, acred->cred->fsgid))
+		return 0;
 
-	if (!uid_eq(cred->uc_uid, acred->uid) || !gid_eq(cred->uc_gid, acred->gid))
+	if (acred->cred->group_info != NULL)
+		groups = acred->cred->group_info->ngroups;
+	if (groups > UNX_NGROUPS)
+		groups = UNX_NGROUPS;
+	if (cred->cr_cred->group_info == NULL)
+		return groups == 0;
+	if (groups != cred->cr_cred->group_info->ngroups)
 		return 0;
 
-	if (acred->group_info != NULL)
-		groups = acred->group_info->ngroups;
-	if (groups > NFS_NGROUPS)
-		groups = NFS_NGROUPS;
 	for (i = 0; i < groups ; i++)
-		if (!gid_eq(cred->uc_gids[i], GROUP_AT(acred->group_info, i)))
+		if (!gid_eq(cred->cr_cred->group_info->gid[i], acred->cred->group_info->gid[i]))
 			return 0;
-	if (groups < NFS_NGROUPS && gid_valid(cred->uc_gids[groups]))
-		return 0;
 	return 1;
 }
 
@@ -140,35 +107,56 @@ unx_match(struct auth_cred *acred, struct rpc_cred *rcred, int flags)
  * Marshal credentials.
  * Maybe we should keep a cached credential for performance reasons.
  */
-static __be32 *
-unx_marshal(struct rpc_task *task, __be32 *p)
+static int
+unx_marshal(struct rpc_task *task, struct xdr_stream *xdr)
 {
 	struct rpc_clnt	*clnt = task->tk_client;
-	struct unx_cred	*cred = container_of(task->tk_rqstp->rq_cred, struct unx_cred, uc_base);
-	__be32		*base, *hold;
+	struct rpc_cred	*cred = task->tk_rqstp->rq_cred;
+	__be32		*p, *cred_len, *gidarr_len;
 	int		i;
+	struct group_info *gi = cred->cr_cred->group_info;
+	struct user_namespace *userns = clnt->cl_cred ?
+		clnt->cl_cred->user_ns : &init_user_ns;
+
+	/* Credential */
+
+	p = xdr_reserve_space(xdr, 3 * sizeof(*p));
+	if (!p)
+		goto marshal_failed;
+	*p++ = rpc_auth_unix;
+	cred_len = p++;
+	*p++ = xdr_zero;	/* stamp */
+	if (xdr_stream_encode_opaque(xdr, clnt->cl_nodename,
+				     clnt->cl_nodelen) < 0)
+		goto marshal_failed;
+	p = xdr_reserve_space(xdr, 3 * sizeof(*p));
+	if (!p)
+		goto marshal_failed;
+	*p++ = cpu_to_be32(from_kuid_munged(userns, cred->cr_cred->fsuid));
+	*p++ = cpu_to_be32(from_kgid_munged(userns, cred->cr_cred->fsgid));
+
+	gidarr_len = p++;
+	if (gi)
+		for (i = 0; i < UNX_NGROUPS && i < gi->ngroups; i++)
+			*p++ = cpu_to_be32(from_kgid_munged(userns, gi->gid[i]));
+	*gidarr_len = cpu_to_be32(p - gidarr_len - 1);
+	*cred_len = cpu_to_be32((p - cred_len - 1) << 2);
+	p = xdr_reserve_space(xdr, (p - gidarr_len - 1) << 2);
+	if (!p)
+		goto marshal_failed;
+
+	/* Verifier */
+
+	p = xdr_reserve_space(xdr, 2 * sizeof(*p));
+	if (!p)
+		goto marshal_failed;
+	*p++ = rpc_auth_null;
+	*p   = xdr_zero;
 
-	*p++ = htonl(RPC_AUTH_UNIX);
-	base = p++;
-	*p++ = htonl(jiffies/HZ);
-
-	/*
-	 * Copy the UTS nodename captured when the client was created.
-	 */
-	p = xdr_encode_array(p, clnt->cl_nodename, clnt->cl_nodelen);
-
-	*p++ = htonl((u32) from_kuid(&init_user_ns, cred->uc_uid));
-	*p++ = htonl((u32) from_kgid(&init_user_ns, cred->uc_gid));
-	hold = p++;
-	for (i = 0; i < 16 && gid_valid(cred->uc_gids[i]); i++)
-		*p++ = htonl((u32) from_kgid(&init_user_ns, cred->uc_gids[i]));
-	*hold = htonl(p - hold - 1);		/* gid array length */
-	*base = htonl((p - base - 1) << 2);	/* cred length */
-
-	*p++ = htonl(RPC_AUTH_NULL);
-	*p++ = htonl(0);
+	return 0;
 
-	return p;
+marshal_failed:
+	return -EMSGSIZE;
 }
 
 /*
@@ -181,39 +169,46 @@ unx_refresh(struct rpc_task *task)
 	return 0;
 }
 
-static __be32 *
-unx_validate(struct rpc_task *task, __be32 *p)
+static int
+unx_validate(struct rpc_task *task, struct xdr_stream *xdr)
 {
-	rpc_authflavor_t	flavor;
-	u32			size;
-
-	flavor = ntohl(*p++);
-	if (flavor != RPC_AUTH_NULL &&
-	    flavor != RPC_AUTH_UNIX &&
-	    flavor != RPC_AUTH_SHORT) {
-		printk("RPC: bad verf flavor: %u\n", flavor);
-		return NULL;
+	struct rpc_auth *auth = task->tk_rqstp->rq_cred->cr_auth;
+	__be32 *p;
+	u32 size;
+
+	p = xdr_inline_decode(xdr, 2 * sizeof(*p));
+	if (!p)
+		return -EIO;
+	switch (*p++) {
+	case rpc_auth_null:
+	case rpc_auth_unix:
+	case rpc_auth_short:
+		break;
+	default:
+		return -EIO;
 	}
-
-	size = ntohl(*p++);
-	if (size > RPC_MAX_AUTH_SIZE) {
-		printk("RPC: giant verf size: %u\n", size);
-		return NULL;
-	}
-	task->tk_rqstp->rq_cred->cr_auth->au_rslack = (size >> 2) + 2;
-	p += (size >> 2);
-
-	return p;
+	size = be32_to_cpup(p);
+	if (size > RPC_MAX_AUTH_SIZE)
+		return -EIO;
+	p = xdr_inline_decode(xdr, size);
+	if (!p)
+		return -EIO;
+
+	auth->au_verfsize = XDR_QUADLEN(size) + 2;
+	auth->au_rslack = XDR_QUADLEN(size) + 2;
+	auth->au_ralign = XDR_QUADLEN(size) + 2;
+	return 0;
 }
 
 int __init rpc_init_authunix(void)
 {
-	return rpcauth_init_credcache(&unix_auth);
+	unix_pool = mempool_create_kmalloc_pool(16, sizeof(struct rpc_cred));
+	return unix_pool ? 0 : -ENOMEM;
 }
 
 void rpc_destroy_authunix(void)
 {
-	rpcauth_destroy_credcache(&unix_auth);
+	mempool_destroy(unix_pool);
 }
 
 const struct rpc_authops authunix_ops = {
@@ -223,25 +218,26 @@ const struct rpc_authops authunix_ops = {
 	.create		= unx_create,
 	.destroy	= unx_destroy,
 	.lookup_cred	= unx_lookup_cred,
-	.crcreate	= unx_create_cred,
 };
 
 static
 struct rpc_auth		unix_auth = {
-	.au_cslack	= UNX_WRITESLACK,
-	.au_rslack	= 2,			/* assume AUTH_NULL verf */
+	.au_cslack	= UNX_CALLSLACK,
+	.au_rslack	= NUL_REPLYSLACK,
+	.au_verfsize	= NUL_REPLYSLACK,
 	.au_ops		= &authunix_ops,
 	.au_flavor	= RPC_AUTH_UNIX,
-	.au_count	= ATOMIC_INIT(0),
+	.au_count	= REFCOUNT_INIT(1),
 };
 
 static
 const struct rpc_credops unix_credops = {
 	.cr_name	= "AUTH_UNIX",
 	.crdestroy	= unx_destroy_cred,
-	.crbind		= rpcauth_generic_bind_cred,
 	.crmatch	= unx_match,
 	.crmarshal	= unx_marshal,
+	.crwrap_req	= rpcauth_wrap_req_encode,
 	.crrefresh	= unx_refresh,
 	.crvalidate	= unx_validate,
+	.crunwrap_resp	= rpcauth_unwrap_resp_decode,
 };