Revert "Merge tag 'keys-acl-20190703' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs"

This reverts merge 0f75ef6a9cff49ff612f7ce0578bced9d0b38325 (and thus
effectively commits

   7a1ade847596 ("keys: Provide KEYCTL_GRANT_PERMISSION")
   2e12256b9a76 ("keys: Replace uid/gid/perm permissions checking with an ACL")

that the merge brought in).

It turns out that it breaks booting with an encrypted volume, and Eric
biggers reports that it also breaks the fscrypt tests [1] and loading of
in-kernel X.509 certificates [2].

The root cause of all the breakage is likely the same, but David Howells
is off email so rather than try to work it out it's getting reverted in
order to not impact the rest of the merge window.

 [1] https://lore.kernel.org/lkml/20190710011559.GA7973@sol.localdomain/
 [2] https://lore.kernel.org/lkml/20190710013225.GB7973@sol.localdomain/

Link: https://lore.kernel.org/lkml/CAHk-=wjxoeMJfeBahnWH=9zShKp2bsVy527vo3_y8HfOdhwAAw@mail.gmail.com/
Reported-by: Eric Biggers <ebiggers@kernel.org>
Cc: David Howells <dhowells@redhat.com>
Cc: James Morris <jmorris@namei.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

5 files changed, 14 insertions, 40 deletions

diff --git a/net/ceph/ceph_common.c b/net/ceph/ceph_common.c
index 38de80d01aae..1c811c74bfc0 100644
--- a/net/ceph/ceph_common.c
+++ b/net/ceph/ceph_common.c
@@ -306,7 +306,7 @@ static int get_secret(struct ceph_crypto_key *dst, const char *name) {
 	int err = 0;
 	struct ceph_crypto_key *ckey;
 
-	ukey = request_key(&key_type_ceph, name, NULL, NULL);
+	ukey = request_key(&key_type_ceph, name, NULL);
 	if (IS_ERR(ukey)) {
 		/* request_key errors don't map nicely to mount(2)
 		   errors; don't even try, but still printk */
diff --git a/net/dns_resolver/dns_key.c b/net/dns_resolver/dns_key.c
index 6b201531b165..3e1a90669006 100644
--- a/net/dns_resolver/dns_key.c
+++ b/net/dns_resolver/dns_key.c
@@ -46,15 +46,6 @@ const struct cred *dns_resolver_cache;
 
 #define	DNS_ERRORNO_OPTION	"dnserror"
 
-static struct key_acl dns_keyring_acl = {
-	.usage	= REFCOUNT_INIT(1),
-	.nr_ace	= 2,
-	.aces = {
-		KEY_POSSESSOR_ACE(KEY_ACE_SEARCH | KEY_ACE_WRITE),
-		KEY_OWNER_ACE(KEY_ACE_VIEW | KEY_ACE_READ | KEY_ACE_CLEAR),
-	}
-};
-
 /*
  * Preparse instantiation data for a dns_resolver key.
  *
@@ -352,7 +343,8 @@ static int __init init_dns_resolver(void)
 
 	keyring = keyring_alloc(".dns_resolver",
 				GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred,
-				&dns_keyring_acl,
+				(KEY_POS_ALL & ~KEY_POS_SETATTR) |
+				KEY_USR_VIEW | KEY_USR_READ,
 				KEY_ALLOC_NOT_IN_QUOTA, NULL, NULL);
 	if (IS_ERR(keyring)) {
 		ret = PTR_ERR(keyring);
diff --git a/net/dns_resolver/dns_query.c b/net/dns_resolver/dns_query.c
index 236baf2bfa4c..cab4e0df924f 100644
--- a/net/dns_resolver/dns_query.c
+++ b/net/dns_resolver/dns_query.c
@@ -47,16 +47,6 @@
 
 #include "internal.h"
 
-static struct key_acl dns_key_acl = {
-	.usage	= REFCOUNT_INIT(1),
-	.nr_ace	= 2,
-	.possessor_viewable = true,
-	.aces = {
-		KEY_POSSESSOR_ACE(KEY_ACE_VIEW | KEY_ACE_SEARCH | KEY_ACE_READ),
-		KEY_OWNER_ACE(KEY_ACE_VIEW | KEY_ACE_INVAL),
-	}
-};
-
 /**
  * dns_query - Query the DNS
  * @net: The network namespace to operate in.
@@ -135,8 +125,7 @@ int dns_query(struct net *net,
 	 * add_key() to preinstall malicious redirections
 	 */
 	saved_cred = override_creds(dns_resolver_cache);
-	rkey = request_key_net(&key_type_dns_resolver, desc, net, options,
-			       &dns_key_acl);
+	rkey = request_key_net(&key_type_dns_resolver, desc, net, options);
 	revert_creds(saved_cred);
 	kfree(desc);
 	if (IS_ERR(rkey)) {
@@ -146,6 +135,8 @@ int dns_query(struct net *net,
 
 	down_read(&rkey->sem);
 	set_bit(KEY_FLAG_ROOT_CAN_INVAL, &rkey->flags);
+	rkey->perm |= KEY_USR_VIEW;
+
 	ret = key_validate(rkey);
 	if (ret < 0)
 		goto put;
diff --git a/net/rxrpc/key.c b/net/rxrpc/key.c
index 2032f6a8225e..6c3f35fac42d 100644
--- a/net/rxrpc/key.c
+++ b/net/rxrpc/key.c
@@ -23,14 +23,6 @@
 #include <keys/user-type.h>
 #include "ar-internal.h"
 
-static struct key_acl rxrpc_null_key_acl = {
-	.usage	= REFCOUNT_INIT(1),
-	.nr_ace	= 1,
-	.aces = {
-		KEY_POSSESSOR_ACE(KEY_ACE_SEARCH | KEY_ACE_READ),
-	}
-};
-
 static int rxrpc_vet_description_s(const char *);
 static int rxrpc_preparse(struct key_preparsed_payload *);
 static int rxrpc_preparse_s(struct key_preparsed_payload *);
@@ -918,8 +910,7 @@ int rxrpc_request_key(struct rxrpc_sock *rx, char __user *optval, int optlen)
 	if (IS_ERR(description))
 		return PTR_ERR(description);
 
-	key = request_key_net(&key_type_rxrpc, description, sock_net(&rx->sk),
-			      NULL, NULL);
+	key = request_key_net(&key_type_rxrpc, description, sock_net(&rx->sk), NULL);
 	if (IS_ERR(key)) {
 		kfree(description);
 		_leave(" = %ld", PTR_ERR(key));
@@ -950,8 +941,7 @@ int rxrpc_server_keyring(struct rxrpc_sock *rx, char __user *optval,
 	if (IS_ERR(description))
 		return PTR_ERR(description);
 
-	key = request_key_net(&key_type_keyring, description, sock_net(&rx->sk),
-			      NULL, NULL);
+	key = request_key_net(&key_type_keyring, description, sock_net(&rx->sk), NULL);
 	if (IS_ERR(key)) {
 		kfree(description);
 		_leave(" = %ld", PTR_ERR(key));
@@ -984,8 +974,7 @@ int rxrpc_get_server_data_key(struct rxrpc_connection *conn,
 	_enter("");
 
 	key = key_alloc(&key_type_rxrpc, "x",
-			GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred,
-			&internal_key_acl,
+			GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred, 0,
 			KEY_ALLOC_NOT_IN_QUOTA, NULL);
 	if (IS_ERR(key)) {
 		_leave(" = -ENOMEM [alloc %ld]", PTR_ERR(key));
@@ -1033,7 +1022,7 @@ struct key *rxrpc_get_null_key(const char *keyname)
 
 	key = key_alloc(&key_type_rxrpc, keyname,
 			GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred,
-			&rxrpc_null_key_acl, KEY_ALLOC_NOT_IN_QUOTA, NULL);
+			KEY_POS_SEARCH, KEY_ALLOC_NOT_IN_QUOTA, NULL);
 	if (IS_ERR(key))
 		return key;
 
diff --git a/net/wireless/reg.c b/net/wireless/reg.c
index 298fe91557f7..4831ad745f91 100644
--- a/net/wireless/reg.c
+++ b/net/wireless/reg.c
@@ -741,7 +741,8 @@ static void __init load_keys_from_buffer(const u8 *p, unsigned int buflen)
 
 		key = key_create_or_update(make_key_ref(builtin_regdb_keys, 1),
 					   "asymmetric", NULL, p, plen,
-					   &internal_key_acl, 
+					   ((KEY_POS_ALL & ~KEY_POS_SETATTR) |
+					    KEY_USR_VIEW | KEY_USR_READ),
 					   KEY_ALLOC_NOT_IN_QUOTA |
 					   KEY_ALLOC_BUILT_IN |
 					   KEY_ALLOC_BYPASS_RESTRICTION);
@@ -767,7 +768,8 @@ static int __init load_builtin_regdb_keys(void)
 	builtin_regdb_keys =
 		keyring_alloc(".builtin_regdb_keys",
 			      KUIDT_INIT(0), KGIDT_INIT(0), current_cred(),
-			      &internal_keyring_acl, 
+			      ((KEY_POS_ALL & ~KEY_POS_SETATTR) |
+			      KEY_USR_VIEW | KEY_USR_READ | KEY_USR_SEARCH),
 			      KEY_ALLOC_NOT_IN_QUOTA, NULL, NULL);
 	if (IS_ERR(builtin_regdb_keys))
 		return PTR_ERR(builtin_regdb_keys);