Update Linux to v5.4.148

Sourced from [1]

[1] https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.4.148.tar.gz

Change-Id: Ib3d26c5ba9b022e2e03533005c4fed4d7c30b61b
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/security/selinux/avc.c b/security/selinux/avc.c
index ecd3829..4a744b1 100644
--- a/security/selinux/avc.c
+++ b/security/selinux/avc.c
@@ -294,26 +294,27 @@
 	struct avc_xperms_decision_node *xpd_node;
 	struct extended_perms_decision *xpd;
 
-	xpd_node = kmem_cache_zalloc(avc_xperms_decision_cachep, GFP_NOWAIT);
+	xpd_node = kmem_cache_zalloc(avc_xperms_decision_cachep,
+				     GFP_NOWAIT | __GFP_NOWARN);
 	if (!xpd_node)
 		return NULL;
 
 	xpd = &xpd_node->xpd;
 	if (which & XPERMS_ALLOWED) {
 		xpd->allowed = kmem_cache_zalloc(avc_xperms_data_cachep,
-						GFP_NOWAIT);
+						GFP_NOWAIT | __GFP_NOWARN);
 		if (!xpd->allowed)
 			goto error;
 	}
 	if (which & XPERMS_AUDITALLOW) {
 		xpd->auditallow = kmem_cache_zalloc(avc_xperms_data_cachep,
-						GFP_NOWAIT);
+						GFP_NOWAIT | __GFP_NOWARN);
 		if (!xpd->auditallow)
 			goto error;
 	}
 	if (which & XPERMS_DONTAUDIT) {
 		xpd->dontaudit = kmem_cache_zalloc(avc_xperms_data_cachep,
-						GFP_NOWAIT);
+						GFP_NOWAIT | __GFP_NOWARN);
 		if (!xpd->dontaudit)
 			goto error;
 	}
@@ -341,7 +342,7 @@
 {
 	struct avc_xperms_node *xp_node;
 
-	xp_node = kmem_cache_zalloc(avc_xperms_cachep, GFP_NOWAIT);
+	xp_node = kmem_cache_zalloc(avc_xperms_cachep, GFP_NOWAIT | __GFP_NOWARN);
 	if (!xp_node)
 		return xp_node;
 	INIT_LIST_HEAD(&xp_node->xpd_head);
@@ -424,7 +425,7 @@
 	if (likely(!audited))
 		return 0;
 	return slow_avc_audit(state, ssid, tsid, tclass, requested,
-			audited, denied, result, ad, 0);
+			audited, denied, result, ad);
 }
 
 static void avc_node_free(struct rcu_head *rhead)
@@ -497,7 +498,7 @@
 {
 	struct avc_node *node;
 
-	node = kmem_cache_zalloc(avc_node_cachep, GFP_NOWAIT);
+	node = kmem_cache_zalloc(avc_node_cachep, GFP_NOWAIT | __GFP_NOWARN);
 	if (!node)
 		goto out;
 
@@ -617,40 +618,37 @@
 	struct avc_node *pos, *node = NULL;
 	int hvalue;
 	unsigned long flag;
+	spinlock_t *lock;
+	struct hlist_head *head;
 
 	if (avc_latest_notif_update(avc, avd->seqno, 1))
-		goto out;
+		return NULL;
 
 	node = avc_alloc_node(avc);
-	if (node) {
-		struct hlist_head *head;
-		spinlock_t *lock;
-		int rc = 0;
+	if (!node)
+		return NULL;
 
-		hvalue = avc_hash(ssid, tsid, tclass);
-		avc_node_populate(node, ssid, tsid, tclass, avd);
-		rc = avc_xperms_populate(node, xp_node);
-		if (rc) {
-			kmem_cache_free(avc_node_cachep, node);
-			return NULL;
-		}
-		head = &avc->avc_cache.slots[hvalue];
-		lock = &avc->avc_cache.slots_lock[hvalue];
-
-		spin_lock_irqsave(lock, flag);
-		hlist_for_each_entry(pos, head, list) {
-			if (pos->ae.ssid == ssid &&
-			    pos->ae.tsid == tsid &&
-			    pos->ae.tclass == tclass) {
-				avc_node_replace(avc, node, pos);
-				goto found;
-			}
-		}
-		hlist_add_head_rcu(&node->list, head);
-found:
-		spin_unlock_irqrestore(lock, flag);
+	avc_node_populate(node, ssid, tsid, tclass, avd);
+	if (avc_xperms_populate(node, xp_node)) {
+		avc_node_kill(avc, node);
+		return NULL;
 	}
-out:
+
+	hvalue = avc_hash(ssid, tsid, tclass);
+	head = &avc->avc_cache.slots[hvalue];
+	lock = &avc->avc_cache.slots_lock[hvalue];
+	spin_lock_irqsave(lock, flag);
+	hlist_for_each_entry(pos, head, list) {
+		if (pos->ae.ssid == ssid &&
+			pos->ae.tsid == tsid &&
+			pos->ae.tclass == tclass) {
+			avc_node_replace(avc, node, pos);
+			goto found;
+		}
+	}
+	hlist_add_head_rcu(&node->list, head);
+found:
+	spin_unlock_irqrestore(lock, flag);
 	return node;
 }
 
@@ -758,8 +756,7 @@
 noinline int slow_avc_audit(struct selinux_state *state,
 			    u32 ssid, u32 tsid, u16 tclass,
 			    u32 requested, u32 audited, u32 denied, int result,
-			    struct common_audit_data *a,
-			    unsigned int flags)
+			    struct common_audit_data *a)
 {
 	struct common_audit_data stack_data;
 	struct selinux_audit_data sad;
@@ -772,17 +769,6 @@
 		a->type = LSM_AUDIT_DATA_NONE;
 	}
 
-	/*
-	 * When in a RCU walk do the audit on the RCU retry.  This is because
-	 * the collection of the dname in an inode audit message is not RCU
-	 * safe.  Note this may drop some audits when the situation changes
-	 * during retry. However this is logically just as if the operation
-	 * happened a little later.
-	 */
-	if ((a->type == LSM_AUDIT_DATA_INODE) &&
-	    (flags & MAY_NOT_BLOCK))
-		return -ECHILD;
-
 	sad.tclass = tclass;
 	sad.requested = requested;
 	sad.ssid = ssid;
@@ -855,15 +841,14 @@
 	/*
 	 * If we are in a non-blocking code path, e.g. VFS RCU walk,
 	 * then we must not add permissions to a cache entry
-	 * because we cannot safely audit the denial.  Otherwise,
+	 * because we will not audit the denial.  Otherwise,
 	 * during the subsequent blocking retry (e.g. VFS ref walk), we
 	 * will find the permissions already granted in the cache entry
 	 * and won't audit anything at all, leading to silent denials in
 	 * permissive mode that only appear when in enforcing mode.
 	 *
-	 * See the corresponding handling in slow_avc_audit(), and the
-	 * logic in selinux_inode_permission for the MAY_NOT_BLOCK flag,
-	 * which is transliterated into AVC_NONBLOCKING.
+	 * See the corresponding handling of MAY_NOT_BLOCK in avc_audit()
+	 * and selinux_inode_permission().
 	 */
 	if (flags & AVC_NONBLOCKING)
 		return 0;
@@ -907,7 +892,7 @@
 	if (orig->ae.xp_node) {
 		rc = avc_xperms_populate(node, orig->ae.xp_node);
 		if (rc) {
-			kmem_cache_free(avc_node_cachep, node);
+			avc_node_kill(avc, node);
 			goto out_unlock;
 		}
 	}
@@ -1205,6 +1190,25 @@
 	return rc;
 }
 
+int avc_has_perm_flags(struct selinux_state *state,
+		       u32 ssid, u32 tsid, u16 tclass, u32 requested,
+		       struct common_audit_data *auditdata,
+		       int flags)
+{
+	struct av_decision avd;
+	int rc, rc2;
+
+	rc = avc_has_perm_noaudit(state, ssid, tsid, tclass, requested,
+				  (flags & MAY_NOT_BLOCK) ? AVC_NONBLOCKING : 0,
+				  &avd);
+
+	rc2 = avc_audit(state, ssid, tsid, tclass, requested, &avd, rc,
+			auditdata, flags);
+	if (rc2)
+		return rc2;
+	return rc;
+}
+
 u32 avc_policy_seqno(struct selinux_state *state)
 {
 	return state->avc->avc_cache.latest_notif;
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 9625b99..717a398 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -1499,7 +1499,7 @@
 			 * inode_doinit with a dentry, before these inodes could
 			 * be used again by userspace.
 			 */
-			goto out;
+			goto out_invalid;
 		}
 
 		rc = inode_doinit_use_xattr(inode, dentry, sbsec->def_sid,
@@ -1554,7 +1554,7 @@
 			 * could be used again by userspace.
 			 */
 			if (!dentry)
-				goto out;
+				goto out_invalid;
 			rc = selinux_genfs_get_sid(dentry, sclass,
 						   sbsec->flags, &sid);
 			if (rc) {
@@ -1579,11 +1579,10 @@
 out:
 	spin_lock(&isec->lock);
 	if (isec->initialized == LABEL_PENDING) {
-		if (!sid || rc) {
+		if (rc) {
 			isec->initialized = LABEL_INVALID;
 			goto out_unlock;
 		}
-
 		isec->initialized = LABEL_INITIALIZED;
 		isec->sid = sid;
 	}
@@ -1591,6 +1590,15 @@
 out_unlock:
 	spin_unlock(&isec->lock);
 	return rc;
+
+out_invalid:
+	spin_lock(&isec->lock);
+	if (isec->initialized == LABEL_PENDING) {
+		isec->initialized = LABEL_INVALID;
+		isec->sid = sid;
+	}
+	spin_unlock(&isec->lock);
+	return 0;
 }
 
 /* Convert a Linux signal to an access vector. */
@@ -2766,6 +2774,14 @@
 		return path_has_perm(cred, path, FILE__MOUNTON);
 }
 
+static int selinux_move_mount(const struct path *from_path,
+			      const struct path *to_path)
+{
+	const struct cred *cred = current_cred();
+
+	return path_has_perm(cred, to_path, FILE__MOUNTON);
+}
+
 static int selinux_umount(struct vfsmount *mnt, int flags)
 {
 	const struct cred *cred = current_cred();
@@ -3008,14 +3024,14 @@
 	if (IS_ERR(isec))
 		return PTR_ERR(isec);
 
-	return avc_has_perm(&selinux_state,
-			    sid, isec->sid, isec->sclass, FILE__READ, &ad);
+	return avc_has_perm_flags(&selinux_state,
+				  sid, isec->sid, isec->sclass, FILE__READ, &ad,
+				  rcu ? MAY_NOT_BLOCK : 0);
 }
 
 static noinline int audit_inode_permission(struct inode *inode,
 					   u32 perms, u32 audited, u32 denied,
-					   int result,
-					   unsigned flags)
+					   int result)
 {
 	struct common_audit_data ad;
 	struct inode_security_struct *isec = selinux_inode(inode);
@@ -3026,7 +3042,7 @@
 
 	rc = slow_avc_audit(&selinux_state,
 			    current_sid(), isec->sid, isec->sclass, perms,
-			    audited, denied, result, &ad, flags);
+			    audited, denied, result, &ad);
 	if (rc)
 		return rc;
 	return 0;
@@ -3073,7 +3089,11 @@
 	if (likely(!audited))
 		return rc;
 
-	rc2 = audit_inode_permission(inode, perms, audited, denied, rc, flags);
+	/* fall back to ref-walk if we have to generate audit */
+	if (flags & MAY_NOT_BLOCK)
+		return -ECHILD;
+
+	rc2 = audit_inode_permission(inode, perms, audited, denied, rc);
 	if (rc2)
 		return rc2;
 	return rc;
@@ -3144,6 +3164,9 @@
 		return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
 	}
 
+	if (!selinux_state.initialized)
+		return (inode_owner_or_capable(inode) ? 0 : -EPERM);
+
 	sbsec = inode->i_sb->s_security;
 	if (!(sbsec->flags & SBLABEL_MNT))
 		return -EOPNOTSUPP;
@@ -3227,6 +3250,15 @@
 		return;
 	}
 
+	if (!selinux_state.initialized) {
+		/* If we haven't even been initialized, then we can't validate
+		 * against a policy, so leave the label as invalid. It may
+		 * resolve to a valid label on the next revalidation try if
+		 * we've since initialized.
+		 */
+		return;
+	}
+
 	rc = security_context_to_sid_force(&selinux_state, value, size,
 					   &newsid);
 	if (rc) {
@@ -5509,40 +5541,60 @@
 
 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
 {
-	int err = 0;
-	u32 perm;
+	int rc = 0;
+	unsigned int msg_len;
+	unsigned int data_len = skb->len;
+	unsigned char *data = skb->data;
 	struct nlmsghdr *nlh;
 	struct sk_security_struct *sksec = sk->sk_security;
+	u16 sclass = sksec->sclass;
+	u32 perm;
 
-	if (skb->len < NLMSG_HDRLEN) {
-		err = -EINVAL;
-		goto out;
-	}
-	nlh = nlmsg_hdr(skb);
+	while (data_len >= nlmsg_total_size(0)) {
+		nlh = (struct nlmsghdr *)data;
 
-	err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
-	if (err) {
-		if (err == -EINVAL) {
+		/* NOTE: the nlmsg_len field isn't reliably set by some netlink
+		 *       users which means we can't reject skb's with bogus
+		 *       length fields; our solution is to follow what
+		 *       netlink_rcv_skb() does and simply skip processing at
+		 *       messages with length fields that are clearly junk
+		 */
+		if (nlh->nlmsg_len < NLMSG_HDRLEN || nlh->nlmsg_len > data_len)
+			return 0;
+
+		rc = selinux_nlmsg_lookup(sclass, nlh->nlmsg_type, &perm);
+		if (rc == 0) {
+			rc = sock_has_perm(sk, perm);
+			if (rc)
+				return rc;
+		} else if (rc == -EINVAL) {
+			/* -EINVAL is a missing msg/perm mapping */
 			pr_warn_ratelimited("SELinux: unrecognized netlink"
-			       " message: protocol=%hu nlmsg_type=%hu sclass=%s"
-			       " pig=%d comm=%s\n",
-			       sk->sk_protocol, nlh->nlmsg_type,
-			       secclass_map[sksec->sclass - 1].name,
-			       task_pid_nr(current), current->comm);
-			if (!enforcing_enabled(&selinux_state) ||
-			    security_get_allow_unknown(&selinux_state))
-				err = 0;
+				" message: protocol=%hu nlmsg_type=%hu sclass=%s"
+				" pid=%d comm=%s\n",
+				sk->sk_protocol, nlh->nlmsg_type,
+				secclass_map[sclass - 1].name,
+				task_pid_nr(current), current->comm);
+			if (enforcing_enabled(&selinux_state) &&
+			    !security_get_allow_unknown(&selinux_state))
+				return rc;
+			rc = 0;
+		} else if (rc == -ENOENT) {
+			/* -ENOENT is a missing socket/class mapping, ignore */
+			rc = 0;
+		} else {
+			return rc;
 		}
 
-		/* Ignore */
-		if (err == -ENOENT)
-			err = 0;
-		goto out;
+		/* move to the next message after applying netlink padding */
+		msg_len = NLMSG_ALIGN(nlh->nlmsg_len);
+		if (msg_len >= data_len)
+			return 0;
+		data_len -= msg_len;
+		data += msg_len;
 	}
 
-	err = sock_has_perm(sk, perm);
-out:
-	return err;
+	return rc;
 }
 
 #ifdef CONFIG_NETFILTER
@@ -6834,6 +6886,8 @@
 	LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts),
 	LSM_HOOK_INIT(sb_add_mnt_opt, selinux_add_mnt_opt),
 
+	LSM_HOOK_INIT(move_mount, selinux_move_mount),
+
 	LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security),
 	LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as),
 
diff --git a/security/selinux/ibpkey.c b/security/selinux/ibpkey.c
index de92365..5887bff 100644
--- a/security/selinux/ibpkey.c
+++ b/security/selinux/ibpkey.c
@@ -151,8 +151,10 @@
 	 * is valid, it just won't be added to the cache.
 	 */
 	new = kzalloc(sizeof(*new), GFP_ATOMIC);
-	if (!new)
+	if (!new) {
+		ret = -ENOMEM;
 		goto out;
+	}
 
 	new->psec.subnet_prefix = subnet_prefix;
 	new->psec.pkey = pkey_num;
diff --git a/security/selinux/include/avc.h b/security/selinux/include/avc.h
index 7be0e1e..cf4cc3e 100644
--- a/security/selinux/include/avc.h
+++ b/security/selinux/include/avc.h
@@ -100,8 +100,7 @@
 int slow_avc_audit(struct selinux_state *state,
 		   u32 ssid, u32 tsid, u16 tclass,
 		   u32 requested, u32 audited, u32 denied, int result,
-		   struct common_audit_data *a,
-		   unsigned flags);
+		   struct common_audit_data *a);
 
 /**
  * avc_audit - Audit the granting or denial of permissions.
@@ -135,9 +134,12 @@
 	audited = avc_audit_required(requested, avd, result, 0, &denied);
 	if (likely(!audited))
 		return 0;
+	/* fall back to ref-walk if we have to generate audit */
+	if (flags & MAY_NOT_BLOCK)
+		return -ECHILD;
 	return slow_avc_audit(state, ssid, tsid, tclass,
 			      requested, audited, denied, result,
-			      a, flags);
+			      a);
 }
 
 #define AVC_STRICT 1 /* Ignore permissive mode. */
@@ -153,6 +155,11 @@
 		 u32 ssid, u32 tsid,
 		 u16 tclass, u32 requested,
 		 struct common_audit_data *auditdata);
+int avc_has_perm_flags(struct selinux_state *state,
+		       u32 ssid, u32 tsid,
+		       u16 tclass, u32 requested,
+		       struct common_audit_data *auditdata,
+		       int flags);
 
 int avc_has_extended_perms(struct selinux_state *state,
 			   u32 ssid, u32 tsid, u16 tclass, u32 requested,
diff --git a/security/selinux/selinuxfs.c b/security/selinux/selinuxfs.c
index e6c7643..e9eaff9 100644
--- a/security/selinux/selinuxfs.c
+++ b/security/selinux/selinuxfs.c
@@ -1508,6 +1508,7 @@
 		*idx = cpu + 1;
 		return &per_cpu(avc_cache_stats, cpu);
 	}
+	(*idx)++;
 	return NULL;
 }
 
diff --git a/security/selinux/ss/policydb.c b/security/selinux/ss/policydb.c
index 1260f5f..dd7aabd 100644
--- a/security/selinux/ss/policydb.c
+++ b/security/selinux/ss/policydb.c
@@ -2496,6 +2496,7 @@
 	if (rc)
 		goto bad;
 
+	rc = -ENOMEM;
 	p->type_attr_map_array = kvcalloc(p->p_types.nprim,
 					  sizeof(*p->type_attr_map_array),
 					  GFP_KERNEL);
diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c
index a5813c7..f62adf3 100644
--- a/security/selinux/ss/services.c
+++ b/security/selinux/ss/services.c
@@ -2844,8 +2844,12 @@
 	if (*names) {
 		for (i = 0; i < *len; i++)
 			kfree((*names)[i]);
+		kfree(*names);
 	}
 	kfree(*values);
+	*len = 0;
+	*names = NULL;
+	*values = NULL;
 	goto out;
 }