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>

10 files changed, 21 insertions, 78 deletions

diff --git a/fs/afs/security.c b/fs/afs/security.c
index 8866703b2e6c..71e71c07568f 100644
--- a/fs/afs/security.c
+++ b/fs/afs/security.c
@@ -28,7 +28,7 @@ struct key *afs_request_key(struct afs_cell *cell)
 
 	_debug("key %s", cell->anonymous_key->description);
 	key = request_key(&key_type_rxrpc, cell->anonymous_key->description,
-			  NULL, NULL);
+			  NULL);
 	if (IS_ERR(key)) {
 		if (PTR_ERR(key) != -ENOKEY) {
 			_leave(" = %ld", PTR_ERR(key));
diff --git a/fs/cifs/cifs_spnego.c b/fs/cifs/cifs_spnego.c
index d1b439ad0f1a..7f01c6e60791 100644
--- a/fs/cifs/cifs_spnego.c
+++ b/fs/cifs/cifs_spnego.c
@@ -32,25 +32,6 @@
 #include "cifsproto.h"
 static const struct cred *spnego_cred;
 
-static struct key_acl cifs_spnego_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),
-	}
-};
-
-static struct key_acl cifs_spnego_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),
-	}
-};
-
 /* create a new cifs key */
 static int
 cifs_spnego_key_instantiate(struct key *key, struct key_preparsed_payload *prep)
@@ -189,8 +170,7 @@ cifs_get_spnego_key(struct cifs_ses *sesInfo)
 
 	cifs_dbg(FYI, "key description = %s\n", description);
 	saved_cred = override_creds(spnego_cred);
-	spnego_key = request_key(&cifs_spnego_key_type, description, "",
-				 &cifs_spnego_key_acl);
+	spnego_key = request_key(&cifs_spnego_key_type, description, "");
 	revert_creds(saved_cred);
 
 #ifdef CONFIG_CIFS_DEBUG2
@@ -227,7 +207,8 @@ init_cifs_spnego(void)
 
 	keyring = keyring_alloc(".cifs_spnego",
 				GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred,
-				&cifs_spnego_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/fs/cifs/cifsacl.c b/fs/cifs/cifsacl.c
index 78eed72f3af0..1d377b7f2860 100644
--- a/fs/cifs/cifsacl.c
+++ b/fs/cifs/cifsacl.c
@@ -33,25 +33,6 @@
 #include "cifsproto.h"
 #include "cifs_debug.h"
 
-static struct key_acl cifs_idmap_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),
-	}
-};
-
-static struct key_acl cifs_idmap_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),
-	}
-};
-
 /* security id for everyone/world system group */
 static const struct cifs_sid sid_everyone = {
 	1, 1, {0, 0, 0, 0, 0, 1}, {0} };
@@ -317,8 +298,7 @@ id_to_sid(unsigned int cid, uint sidtype, struct cifs_sid *ssid)
 
 	rc = 0;
 	saved_cred = override_creds(root_cred);
-	sidkey = request_key(&cifs_idmap_key_type, desc, "",
-			     &cifs_idmap_key_acl);
+	sidkey = request_key(&cifs_idmap_key_type, desc, "");
 	if (IS_ERR(sidkey)) {
 		rc = -EINVAL;
 		cifs_dbg(FYI, "%s: Can't map %cid %u to a SID\n",
@@ -423,8 +403,7 @@ try_upcall_to_get_id:
 		return -ENOMEM;
 
 	saved_cred = override_creds(root_cred);
-	sidkey = request_key(&cifs_idmap_key_type, sidstr, "",
-			     &cifs_idmap_key_acl);
+	sidkey = request_key(&cifs_idmap_key_type, sidstr, "");
 	if (IS_ERR(sidkey)) {
 		rc = -EINVAL;
 		cifs_dbg(FYI, "%s: Can't map SID %s to a %cid\n",
@@ -502,7 +481,8 @@ init_cifs_idmap(void)
 
 	keyring = keyring_alloc(".cifs_idmap",
 				GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred,
-				&cifs_idmap_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/fs/cifs/connect.c b/fs/cifs/connect.c
index ae6bae2ecb5d..714a359c7c8d 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -2992,7 +2992,7 @@ cifs_set_cifscreds(struct smb_vol *vol, struct cifs_ses *ses)
 	}
 
 	cifs_dbg(FYI, "%s: desc=%s\n", __func__, desc);
-	key = request_key(&key_type_logon, desc, "", NULL);
+	key = request_key(&key_type_logon, desc, "");
 	if (IS_ERR(key)) {
 		if (!ses->domainName) {
 			cifs_dbg(FYI, "domainName is NULL\n");
@@ -3003,7 +3003,7 @@ cifs_set_cifscreds(struct smb_vol *vol, struct cifs_ses *ses)
 		/* didn't work, try to find a domain key */
 		sprintf(desc, "cifs:d:%s", ses->domainName);
 		cifs_dbg(FYI, "%s: desc=%s\n", __func__, desc);
-		key = request_key(&key_type_logon, desc, "", NULL);
+		key = request_key(&key_type_logon, desc, "");
 		if (IS_ERR(key)) {
 			rc = PTR_ERR(key);
 			goto out_err;
diff --git a/fs/crypto/keyinfo.c b/fs/crypto/keyinfo.c
index 4f85af8ab239..dcd91a3fbe49 100644
--- a/fs/crypto/keyinfo.c
+++ b/fs/crypto/keyinfo.c
@@ -92,7 +92,7 @@ find_and_lock_process_key(const char *prefix,
 	if (!description)
 		return ERR_PTR(-ENOMEM);
 
-	key = request_key(&key_type_logon, description, NULL, NULL);
+	key = request_key(&key_type_logon, description, NULL);
 	kfree(description);
 	if (IS_ERR(key))
 		return key;
diff --git a/fs/ecryptfs/ecryptfs_kernel.h b/fs/ecryptfs/ecryptfs_kernel.h
index 67844fe41a61..1c1a56be7ea2 100644
--- a/fs/ecryptfs/ecryptfs_kernel.h
+++ b/fs/ecryptfs/ecryptfs_kernel.h
@@ -91,7 +91,7 @@ ecryptfs_get_encrypted_key_payload_data(struct key *key)
 
 static inline struct key *ecryptfs_get_encrypted_key(char *sig)
 {
-	return request_key(&key_type_encrypted, sig, NULL, NULL);
+	return request_key(&key_type_encrypted, sig, NULL);
 }
 
 #else
diff --git a/fs/ecryptfs/keystore.c b/fs/ecryptfs/keystore.c
index ba382f135918..9536e592e25a 100644
--- a/fs/ecryptfs/keystore.c
+++ b/fs/ecryptfs/keystore.c
@@ -1610,7 +1610,7 @@ int ecryptfs_keyring_auth_tok_for_sig(struct key **auth_tok_key,
 {
 	int rc = 0;
 
-	(*auth_tok_key) = request_key(&key_type_user, sig, NULL, NULL);
+	(*auth_tok_key) = request_key(&key_type_user, sig, NULL);
 	if (!(*auth_tok_key) || IS_ERR(*auth_tok_key)) {
 		(*auth_tok_key) = ecryptfs_get_encrypted_key(sig);
 		if (!(*auth_tok_key) || IS_ERR(*auth_tok_key)) {
diff --git a/fs/fscache/object-list.c b/fs/fscache/object-list.c
index 67b7bda5647a..72ebfe578f40 100644
--- a/fs/fscache/object-list.c
+++ b/fs/fscache/object-list.c
@@ -317,7 +317,7 @@ static void fscache_objlist_config(struct fscache_objlist_data *data)
 	const char *buf;
 	int len;
 
-	key = request_key(&key_type_user, "fscache:objlist", NULL, NULL);
+	key = request_key(&key_type_user, "fscache:objlist", NULL);
 	if (IS_ERR(key))
 		goto no_config;
 
diff --git a/fs/nfs/nfs4idmap.c b/fs/nfs/nfs4idmap.c
index 69679f4f2e6c..1e7296395d71 100644
--- a/fs/nfs/nfs4idmap.c
+++ b/fs/nfs/nfs4idmap.c
@@ -72,25 +72,6 @@ struct idmap {
 	const struct cred	*cred;
 };
 
-static struct key_acl nfs_idmap_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),
-	}
-};
-
-static struct key_acl nfs_idmap_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),
-	}
-};
-
 static struct user_namespace *idmap_userns(const struct idmap *idmap)
 {
 	if (idmap && idmap->cred)
@@ -227,7 +208,8 @@ int nfs_idmap_init(void)
 
 	keyring = keyring_alloc(".id_resolver",
 				GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred,
-				&nfs_idmap_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);
@@ -305,13 +287,11 @@ static struct key *nfs_idmap_request_key(const char *name, size_t namelen,
 		return ERR_PTR(ret);
 
 	if (!idmap->cred || idmap->cred->user_ns == &init_user_ns)
-		rkey = request_key(&key_type_id_resolver, desc, "",
-				   &nfs_idmap_key_acl);
+		rkey = request_key(&key_type_id_resolver, desc, "");
 	if (IS_ERR(rkey)) {
 		mutex_lock(&idmap->idmap_mutex);
 		rkey = request_key_with_auxdata(&key_type_id_resolver_legacy,
-						desc, NULL, "", 0, idmap,
-						&nfs_idmap_key_acl);
+						desc, NULL, "", 0, idmap);
 		mutex_unlock(&idmap->idmap_mutex);
 	}
 	if (!IS_ERR(rkey))
@@ -340,6 +320,8 @@ static ssize_t nfs_idmap_get_key(const char *name, size_t namelen,
 	}
 
 	rcu_read_lock();
+	rkey->perm |= KEY_USR_VIEW;
+
 	ret = key_validate(rkey);
 	if (ret < 0)
 		goto out_up;
diff --git a/fs/ubifs/auth.c b/fs/ubifs/auth.c
index 38718026ad0b..60f43b93d06e 100644
--- a/fs/ubifs/auth.c
+++ b/fs/ubifs/auth.c
@@ -227,7 +227,7 @@ int ubifs_init_authentication(struct ubifs_info *c)
 	snprintf(hmac_name, CRYPTO_MAX_ALG_NAME, "hmac(%s)",
 		 c->auth_hash_name);
 
-	keyring_key = request_key(&key_type_logon, c->auth_key_name, NULL, NULL);
+	keyring_key = request_key(&key_type_logon, c->auth_key_name, NULL);
 
 	if (IS_ERR(keyring_key)) {
 		ubifs_err(c, "Failed to request key: %ld",