Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted

Pull I3C updates from Alexandre Belloni:
 "A new driver this cycle, for the AMD AXI I3C controller.

  There are also new features such as IBI wakeup support, SETAASA device
  discovery and ACPI support for the the DAA methods, meaning we can now
  communicate with the SPD devices on DDR5 modules.

  New driver:
   - AMD AXI I3C master controller

  Subsystem:
   - I3C Common Command Code (CCC) handling improvements, especially
     around GET CCCs
   - SETAASA device discovery support
   - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as
     well as I2C devices on I3C bus
   - IBI-based wakeup support

  Drivers:
   - dw: SETAASA support
   - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C
     controller support, PIO queue management support for HCI v1.2
   - renesas: improve suspend to RAM support, add runtime PM support"

* tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits)
  i3c: dw: reduce do_daa time if there's no client
  i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller
  i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2
  i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode
  i3c: dw: rename "pclk" to "apb" to match dt-binding
  i3c: dw: make struct dw_i3c_cmd smaller
  i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding
  i3c: renesas: Don't register devices when ENTDAA times out
  i3c: master: dw-i3c-master: fix OD timing for first broadcast
  i3c: mipi-i3c-hci: Advertise IBI wakeup capability
  i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev()
  i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI
  i3c: master: Reject IBI requests from non-IBI-capable devices
  i3c: master: Add helper to query bus wakeup requirements
  i3c: master: Report wakeup events for IBIs
  i3c: master: Support IBI-based wakeup capability
  i3c: master: Fix potential UAF in i3c_device_match()
  i3c: master: Fix potential UAF in i3c_device_uevent()
  i3c: Make dev->desc locking assumptions explicit
  i3c: master: Fix use-after-free of master->this
  ...

1 files changed, 490 insertions, 0 deletions

diff --git a/security/ipe/policy_fs.c b/security/ipe/policy_fs.c
new file mode 100644
index 000000000..9d92d8a14
--- /dev/null
+++ b/security/ipe/policy_fs.c
@@ -0,0 +1,490 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2020-2024 Microsoft Corporation. All rights reserved.
+ */
+#include <linux/fs.h>
+#include <linux/namei.h>
+#include <linux/types.h>
+#include <linux/dcache.h>
+#include <linux/security.h>
+
+#include "ipe.h"
+#include "policy.h"
+#include "eval.h"
+#include "fs.h"
+#include "audit.h"
+
+#define MAX_VERSION_SIZE ARRAY_SIZE("65535.65535.65535")
+
+/**
+ * struct ipefs_file - defines a file in securityfs.
+ *
+ * @name: file name inside the policy subdirectory
+ * @access: file permissions
+ * @fops: &file_operations specific to this file
+ */
+struct ipefs_file {
+	const char *name;
+	umode_t access;
+	const struct file_operations *fops;
+};
+
+/**
+ * read_pkcs7() - Read handler for "ipe/policies/$name/pkcs7".
+ * @f: Supplies a file structure representing the securityfs node.
+ * @data: Supplies a buffer passed to the write syscall.
+ * @len: Supplies the length of @data.
+ * @offset: unused.
+ *
+ * @data will be populated with the pkcs7 blob representing the policy
+ * on success. If the policy is unsigned (like the boot policy), this
+ * will return -ENOENT.
+ *
+ * Return:
+ * * Length of buffer written	- Success
+ * * %-ENOENT			- Policy initializing/deleted or is unsigned
+ */
+static ssize_t read_pkcs7(struct file *f, char __user *data,
+			  size_t len, loff_t *offset)
+{
+	const struct ipe_policy *p = NULL;
+	struct inode *root = NULL;
+	int rc = 0;
+
+	root = d_inode(f->f_path.dentry->d_parent);
+
+	inode_lock_shared(root);
+	p = (struct ipe_policy *)root->i_private;
+	if (!p) {
+		rc = -ENOENT;
+		goto out;
+	}
+
+	if (!p->pkcs7) {
+		rc = -ENOENT;
+		goto out;
+	}
+
+	rc = simple_read_from_buffer(data, len, offset, p->pkcs7, p->pkcs7len);
+
+out:
+	inode_unlock_shared(root);
+
+	return rc;
+}
+
+/**
+ * read_policy() - Read handler for "ipe/policies/$name/policy".
+ * @f: Supplies a file structure representing the securityfs node.
+ * @data: Supplies a buffer passed to the write syscall.
+ * @len: Supplies the length of @data.
+ * @offset: unused.
+ *
+ * @data will be populated with the plain-text version of the policy
+ * on success.
+ *
+ * Return:
+ * * Length of buffer written	- Success
+ * * %-ENOENT			- Policy initializing/deleted
+ */
+static ssize_t read_policy(struct file *f, char __user *data,
+			   size_t len, loff_t *offset)
+{
+	const struct ipe_policy *p = NULL;
+	struct inode *root = NULL;
+	int rc = 0;
+
+	root = d_inode(f->f_path.dentry->d_parent);
+
+	inode_lock_shared(root);
+	p = (struct ipe_policy *)root->i_private;
+	if (!p) {
+		rc = -ENOENT;
+		goto out;
+	}
+
+	rc = simple_read_from_buffer(data, len, offset, p->text, p->textlen);
+
+out:
+	inode_unlock_shared(root);
+
+	return rc;
+}
+
+/**
+ * read_name() - Read handler for "ipe/policies/$name/name".
+ * @f: Supplies a file structure representing the securityfs node.
+ * @data: Supplies a buffer passed to the write syscall.
+ * @len: Supplies the length of @data.
+ * @offset: unused.
+ *
+ * @data will be populated with the policy_name attribute on success.
+ *
+ * Return:
+ * * Length of buffer written	- Success
+ * * %-ENOENT			- Policy initializing/deleted
+ */
+static ssize_t read_name(struct file *f, char __user *data,
+			 size_t len, loff_t *offset)
+{
+	const struct ipe_policy *p = NULL;
+	struct inode *root = NULL;
+	int rc = 0;
+
+	root = d_inode(f->f_path.dentry->d_parent);
+
+	inode_lock_shared(root);
+	p = (struct ipe_policy *)root->i_private;
+	if (!p) {
+		rc = -ENOENT;
+		goto out;
+	}
+
+	rc = simple_read_from_buffer(data, len, offset, p->parsed->name,
+				     strlen(p->parsed->name));
+
+out:
+	inode_unlock_shared(root);
+
+	return rc;
+}
+
+/**
+ * read_version() - Read handler for "ipe/policies/$name/version".
+ * @f: Supplies a file structure representing the securityfs node.
+ * @data: Supplies a buffer passed to the write syscall.
+ * @len: Supplies the length of @data.
+ * @offset: unused.
+ *
+ * @data will be populated with the version string on success.
+ *
+ * Return:
+ * * Length of buffer written	- Success
+ * * %-ENOENT			- Policy initializing/deleted
+ */
+static ssize_t read_version(struct file *f, char __user *data,
+			    size_t len, loff_t *offset)
+{
+	char buffer[MAX_VERSION_SIZE] = { 0 };
+	const struct ipe_policy *p = NULL;
+	struct inode *root = NULL;
+	size_t strsize = 0;
+	ssize_t rc = 0;
+
+	root = d_inode(f->f_path.dentry->d_parent);
+
+	inode_lock_shared(root);
+	p = (struct ipe_policy *)root->i_private;
+	if (!p) {
+		rc = -ENOENT;
+		goto out;
+	}
+
+	strsize = scnprintf(buffer, ARRAY_SIZE(buffer), "%hu.%hu.%hu",
+			    p->parsed->version.major, p->parsed->version.minor,
+			    p->parsed->version.rev);
+
+	rc = simple_read_from_buffer(data, len, offset, buffer, strsize);
+
+out:
+	inode_unlock_shared(root);
+
+	return rc;
+}
+
+/**
+ * setactive() - Write handler for "ipe/policies/$name/active".
+ * @f: Supplies a file structure representing the securityfs node.
+ * @data: Supplies a buffer passed to the write syscall.
+ * @len: Supplies the length of @data.
+ * @offset: unused.
+ *
+ * Return:
+ * * Length of buffer written	- Success
+ * * %-EPERM			- Insufficient permission
+ * * %-EINVAL			- Invalid input
+ * * %-ENOENT			- Policy initializing/deleted
+ */
+static ssize_t setactive(struct file *f, const char __user *data,
+			 size_t len, loff_t *offset)
+{
+	const struct ipe_policy *p = NULL;
+	struct inode *root = NULL;
+	bool value = false;
+	int rc = 0;
+
+	if (!file_ns_capable(f, &init_user_ns, CAP_MAC_ADMIN))
+		return -EPERM;
+
+	rc = kstrtobool_from_user(data, len, &value);
+	if (rc)
+		return rc;
+
+	if (!value)
+		return -EINVAL;
+
+	root = d_inode(f->f_path.dentry->d_parent);
+	inode_lock(root);
+
+	p = (struct ipe_policy *)root->i_private;
+	if (!p) {
+		rc = -ENOENT;
+		goto out;
+	}
+
+	rc = ipe_set_active_pol(p);
+
+out:
+	inode_unlock(root);
+	return (rc < 0) ? rc : len;
+}
+
+/**
+ * getactive() - Read handler for "ipe/policies/$name/active".
+ * @f: Supplies a file structure representing the securityfs node.
+ * @data: Supplies a buffer passed to the write syscall.
+ * @len: Supplies the length of @data.
+ * @offset: unused.
+ *
+ * @data will be populated with the 1 or 0 depending on if the
+ * corresponding policy is active.
+ *
+ * Return:
+ * * Length of buffer written	- Success
+ * * %-ENOENT			- Policy initializing/deleted
+ */
+static ssize_t getactive(struct file *f, char __user *data,
+			 size_t len, loff_t *offset)
+{
+	const struct ipe_policy *p = NULL;
+	struct inode *root = NULL;
+	const char *str;
+	int rc = 0;
+
+	root = d_inode(f->f_path.dentry->d_parent);
+
+	inode_lock_shared(root);
+	p = (struct ipe_policy *)root->i_private;
+	if (!p) {
+		inode_unlock_shared(root);
+		return -ENOENT;
+	}
+	inode_unlock_shared(root);
+
+	str = (p == rcu_access_pointer(ipe_active_policy)) ? "1" : "0";
+	rc = simple_read_from_buffer(data, len, offset, str, 1);
+
+	return rc;
+}
+
+/**
+ * update_policy() - Write handler for "ipe/policies/$name/update".
+ * @f: Supplies a file structure representing the securityfs node.
+ * @data: Supplies a buffer passed to the write syscall.
+ * @len: Supplies the length of @data.
+ * @offset: unused.
+ *
+ * On success this updates the policy represented by $name,
+ * in-place.
+ *
+ * Return:
+ * * Length of buffer written		- Success
+ * * %-EPERM				- Insufficient permission
+ * * %-ENOMEM				- Out of memory (OOM)
+ * * %-ENOENT				- Policy was deleted while updating
+ * * %-EINVAL				- Policy name mismatch
+ * * %-ESTALE				- Policy version too old
+ */
+static ssize_t update_policy(struct file *f, const char __user *data,
+			     size_t len, loff_t *offset)
+{
+	struct inode *root = NULL;
+	char *copy = NULL;
+	int rc = 0;
+
+	if (!file_ns_capable(f, &init_user_ns, CAP_MAC_ADMIN)) {
+		rc = -EPERM;
+		goto out;
+	}
+
+	copy = memdup_user(data, len);
+	if (IS_ERR(copy)) {
+		rc = PTR_ERR(copy);
+		copy = NULL;
+		goto out;
+	}
+
+	root = d_inode(f->f_path.dentry->d_parent);
+	inode_lock(root);
+	rc = ipe_update_policy(root, NULL, 0, copy, len);
+	inode_unlock(root);
+
+out:
+	kfree(copy);
+	if (rc) {
+		ipe_audit_policy_load(ERR_PTR(rc));
+		return rc;
+	}
+
+	return len;
+}
+
+/**
+ * delete_policy() - write handler for  "ipe/policies/$name/delete".
+ * @f: Supplies a file structure representing the securityfs node.
+ * @data: Supplies a buffer passed to the write syscall.
+ * @len: Supplies the length of @data.
+ * @offset: unused.
+ *
+ * On success this deletes the policy represented by $name.
+ *
+ * Return:
+ * * Length of buffer written	- Success
+ * * %-EPERM			- Insufficient permission/deleting active policy
+ * * %-EINVAL			- Invalid input
+ * * %-ENOENT			- Policy initializing/deleted
+ */
+static ssize_t delete_policy(struct file *f, const char __user *data,
+			     size_t len, loff_t *offset)
+{
+	struct ipe_policy *ap = NULL;
+	struct ipe_policy *p = NULL;
+	struct inode *root = NULL;
+	bool value = false;
+	int rc = 0;
+
+	if (!file_ns_capable(f, &init_user_ns, CAP_MAC_ADMIN))
+		return -EPERM;
+
+	rc = kstrtobool_from_user(data, len, &value);
+	if (rc)
+		return rc;
+
+	if (!value)
+		return -EINVAL;
+
+	root = d_inode(f->f_path.dentry->d_parent);
+	inode_lock(root);
+	p = (struct ipe_policy *)root->i_private;
+	if (!p) {
+		inode_unlock(root);
+		return -ENOENT;
+	}
+
+	mutex_lock(&ipe_policy_lock);
+	ap = rcu_dereference_protected(ipe_active_policy,
+				       lockdep_is_held(&ipe_policy_lock));
+	if (p == ap) {
+		mutex_unlock(&ipe_policy_lock);
+		inode_unlock(root);
+		return -EPERM;
+	}
+	mutex_unlock(&ipe_policy_lock);
+
+	root->i_private = NULL;
+	inode_unlock(root);
+
+	synchronize_rcu();
+	ipe_free_policy(p);
+
+	return len;
+}
+
+static const struct file_operations content_fops = {
+	.read = read_policy,
+};
+
+static const struct file_operations pkcs7_fops = {
+	.read = read_pkcs7,
+};
+
+static const struct file_operations name_fops = {
+	.read = read_name,
+};
+
+static const struct file_operations ver_fops = {
+	.read = read_version,
+};
+
+static const struct file_operations active_fops = {
+	.write = setactive,
+	.read = getactive,
+};
+
+static const struct file_operations update_fops = {
+	.write = update_policy,
+};
+
+static const struct file_operations delete_fops = {
+	.write = delete_policy,
+};
+
+/*
+ * policy_subdir - files under a policy subdirectory
+ */
+static const struct ipefs_file policy_subdir[] = {
+	{ "pkcs7", 0444, &pkcs7_fops },
+	{ "policy", 0444, &content_fops },
+	{ "name", 0444, &name_fops },
+	{ "version", 0444, &ver_fops },
+	{ "active", 0600, &active_fops },
+	{ "update", 0200, &update_fops },
+	{ "delete", 0200, &delete_fops },
+};
+
+/**
+ * ipe_del_policyfs_node() - Delete a securityfs entry for @p.
+ * @p: Supplies a pointer to the policy to delete a securityfs entry for.
+ */
+void ipe_del_policyfs_node(struct ipe_policy *p)
+{
+	securityfs_remove(p->policyfs);
+	p->policyfs = NULL;
+}
+
+/**
+ * ipe_new_policyfs_node() - Create a securityfs entry for @p.
+ * @p: Supplies a pointer to the policy to create a securityfs entry for.
+ *
+ * Return: %0 on success. If an error occurs, the function will return
+ * the -errno.
+ */
+int ipe_new_policyfs_node(struct ipe_policy *p)
+{
+	const struct ipefs_file *f = NULL;
+	struct dentry *policyfs = NULL;
+	struct inode *root = NULL;
+	struct dentry *d = NULL;
+	size_t i = 0;
+	int rc = 0;
+
+	if (p->policyfs)
+		return 0;
+
+	policyfs = securityfs_create_dir(p->parsed->name, policy_root);
+	if (IS_ERR(policyfs))
+		return PTR_ERR(policyfs);
+
+	root = d_inode(policyfs);
+
+	for (i = 0; i < ARRAY_SIZE(policy_subdir); ++i) {
+		f = &policy_subdir[i];
+
+		d = securityfs_create_file(f->name, f->access, policyfs,
+					   NULL, f->fops);
+		if (IS_ERR(d)) {
+			rc = PTR_ERR(d);
+			goto err;
+		}
+	}
+
+	inode_lock(root);
+	p->policyfs = policyfs;
+	root->i_private = p;
+	inode_unlock(root);
+
+	return 0;
+err:
+	securityfs_remove(policyfs);
+	return rc;
+}