1 files changed, 17 insertions, 24 deletions

diff --git a/fs/nfsd/auth.c b/fs/nfsd/auth.c
index 06cddd572264..4dc327e02456 100644
--- a/fs/nfsd/auth.c
+++ b/fs/nfsd/auth.c
@@ -1,44 +1,41 @@
+// SPDX-License-Identifier: GPL-2.0
 /* Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de> */
 
 #include <linux/sched.h>
-#include <linux/user_namespace.h>
 #include "nfsd.h"
 #include "auth.h"
 
-int nfsexp_flags(struct svc_rqst *rqstp, struct svc_export *exp)
+int nfsexp_flags(struct svc_cred *cred, struct svc_export *exp)
 {
 	struct exp_flavor_info *f;
 	struct exp_flavor_info *end = exp->ex_flavors + exp->ex_nflavors;
 
 	for (f = exp->ex_flavors; f < end; f++) {
-		if (f->pseudoflavor == rqstp->rq_cred.cr_flavor)
+		if (f->pseudoflavor == cred->cr_flavor)
 			return f->flags;
 	}
 	return exp->ex_flags;
 
 }
 
-int nfsd_setuser(struct svc_rqst *rqstp, struct svc_export *exp)
+int nfsd_setuser(struct svc_cred *cred, struct svc_export *exp)
 {
 	struct group_info *rqgi;
 	struct group_info *gi;
 	struct cred *new;
 	int i;
-	int flags = nfsexp_flags(rqstp, exp);
-	int ret;
-
-	validate_process_creds();
+	int flags = nfsexp_flags(cred, exp);
 
 	/* discard any old override before preparing the new set */
-	revert_creds(get_cred(current->real_cred));
+	put_cred(revert_creds(get_cred(current_real_cred())));
 	new = prepare_creds();
 	if (!new)
 		return -ENOMEM;
 
-	new->fsuid = rqstp->rq_cred.cr_uid;
-	new->fsgid = rqstp->rq_cred.cr_gid;
+	new->fsuid = cred->cr_uid;
+	new->fsgid = cred->cr_gid;
 
-	rqgi = rqstp->rq_cred.cr_group_info;
+	rqgi = cred->cr_group_info;
 
 	if (flags & NFSEXP_ALLSQUASH) {
 		new->fsuid = exp->ex_anon_uid;
@@ -57,11 +54,14 @@ int nfsd_setuser(struct svc_rqst *rqstp, struct svc_export *exp)
 			goto oom;
 
 		for (i = 0; i < rqgi->ngroups; i++) {
-			if (gid_eq(GLOBAL_ROOT_GID, GROUP_AT(rqgi, i)))
-				GROUP_AT(gi, i) = exp->ex_anon_gid;
+			if (gid_eq(GLOBAL_ROOT_GID, rqgi->gid[i]))
+				gi->gid[i] = exp->ex_anon_gid;
 			else
-				GROUP_AT(gi, i) = GROUP_AT(rqgi, i);
+				gi->gid[i] = rqgi->gid[i];
 		}
+
+		/* Each thread allocates its own gi, no race */
+		groups_sort(gi);
 	} else {
 		gi = get_group_info(rqgi);
 	}
@@ -71,26 +71,19 @@ int nfsd_setuser(struct svc_rqst *rqstp, struct svc_export *exp)
 	if (gid_eq(new->fsgid, INVALID_GID))
 		new->fsgid = exp->ex_anon_gid;
 
-	ret = set_groups(new, gi);
+	set_groups(new, gi);
 	put_group_info(gi);
-	if (ret < 0)
-		goto error;
 
 	if (!uid_eq(new->fsuid, GLOBAL_ROOT_UID))
 		new->cap_effective = cap_drop_nfsd_set(new->cap_effective);
 	else
 		new->cap_effective = cap_raise_nfsd_set(new->cap_effective,
 							new->cap_permitted);
-	validate_process_creds();
 	put_cred(override_creds(new));
-	put_cred(new);
-	validate_process_creds();
 	return 0;
 
 oom:
-	ret = -ENOMEM;
-error:
 	abort_creds(new);
-	return ret;
+	return -ENOMEM;
 }