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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
commit4352b8aee98005853aa63f57d6377282de17a33f (patch)
tree27614d7a9ef05c32d089004e104364ce42324837 /security/apparmor/path.c
downloadlinux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz
linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip
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 ...
Diffstat (limited to 'security/apparmor/path.c')
-rw-r--r--security/apparmor/path.c222
1 files changed, 222 insertions, 0 deletions
diff --git a/security/apparmor/path.c b/security/apparmor/path.c
new file mode 100644
index 000000000..2494e8101
--- /dev/null
+++ b/security/apparmor/path.c
@@ -0,0 +1,222 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * AppArmor security module
+ *
+ * This file contains AppArmor function for pathnames
+ *
+ * Copyright (C) 1998-2008 Novell/SUSE
+ * Copyright 2009-2010 Canonical Ltd.
+ */
+
+#include <linux/magic.h>
+#include <linux/mount.h>
+#include <linux/namei.h>
+#include <linux/nsproxy.h>
+#include <linux/path.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/fs_struct.h>
+
+#include "include/apparmor.h"
+#include "include/path.h"
+#include "include/policy.h"
+
+/* modified from dcache.c */
+static int prepend(char **buffer, int buflen, const char *str, int namelen)
+{
+ buflen -= namelen;
+ if (buflen < 0)
+ return -ENAMETOOLONG;
+ *buffer -= namelen;
+ memcpy(*buffer, str, namelen);
+ return 0;
+}
+
+#define CHROOT_NSCONNECT (PATH_CHROOT_REL | PATH_CHROOT_NSCONNECT)
+
+/* If the path is not connected to the expected root,
+ * check if it is a sysctl and handle specially else remove any
+ * leading / that __d_path may have returned.
+ * Unless
+ * specifically directed to connect the path,
+ * OR
+ * if in a chroot and doing chroot relative paths and the path
+ * resolves to the namespace root (would be connected outside
+ * of chroot) and specifically directed to connect paths to
+ * namespace root.
+ */
+static int disconnect(const struct path *path, char *buf, char **name,
+ int flags, const char *disconnected)
+{
+ int error = 0;
+
+ if (!(flags & PATH_CONNECT_PATH) &&
+ !(((flags & CHROOT_NSCONNECT) == CHROOT_NSCONNECT) &&
+ our_mnt(path->mnt))) {
+ /* disconnected path, don't return pathname starting
+ * with '/'
+ */
+ error = -EACCES;
+ if (**name == '/')
+ *name = *name + 1;
+ } else {
+ if (**name != '/')
+ /* CONNECT_PATH with missing root */
+ error = prepend(name, *name - buf, "/", 1);
+ if (!error && disconnected)
+ error = prepend(name, *name - buf, disconnected,
+ strlen(disconnected));
+ }
+
+ return error;
+}
+
+/**
+ * d_namespace_path - lookup a name associated with a given path
+ * @path: path to lookup (NOT NULL)
+ * @buf: buffer to store path to (NOT NULL)
+ * @name: Returns - pointer for start of path name with in @buf (NOT NULL)
+ * @flags: flags controlling path lookup
+ * @disconnected: string to prefix to disconnected paths
+ *
+ * Handle path name lookup.
+ *
+ * Returns: %0 else error code if path lookup fails
+ * When no error the path name is returned in @name which points to
+ * a position in @buf
+ */
+static int d_namespace_path(const struct path *path, char *buf, char **name,
+ int flags, const char *disconnected)
+{
+ char *res;
+ int error = 0;
+ int connected = 1;
+ int isdir = (flags & PATH_IS_DIR) ? 1 : 0;
+ int buflen = aa_g_path_max - isdir;
+
+ if (path->mnt->mnt_flags & MNT_INTERNAL) {
+ /* it's not mounted anywhere */
+ res = dentry_path(path->dentry, buf, buflen);
+ *name = res;
+ if (IS_ERR(res)) {
+ *name = buf;
+ return PTR_ERR(res);
+ }
+ if (path->dentry->d_sb->s_magic == PROC_SUPER_MAGIC &&
+ strncmp(*name, "/sys/", 5) == 0) {
+ /* TODO: convert over to using a per namespace
+ * control instead of hard coded /proc
+ */
+ error = prepend(name, *name - buf, "/proc", 5);
+ goto out;
+ } else
+ error = disconnect(path, buf, name, flags,
+ disconnected);
+ goto out;
+ }
+
+ /* resolve paths relative to chroot?*/
+ if (flags & PATH_CHROOT_REL) {
+ struct path root;
+ get_fs_root(current->fs, &root);
+ res = __d_path(path, &root, buf, buflen);
+ path_put(&root);
+ } else {
+ res = d_absolute_path(path, buf, buflen);
+ if (!our_mnt(path->mnt))
+ connected = 0;
+ }
+
+ /* handle error conditions - and still allow a partial path to
+ * be returned.
+ */
+ if (IS_ERR_OR_NULL(res)) {
+ if (PTR_ERR(res) == -ENAMETOOLONG) {
+ error = -ENAMETOOLONG;
+ *name = buf;
+ goto out;
+ }
+ connected = 0;
+ res = dentry_path_raw(path->dentry, buf, buflen);
+ if (IS_ERR(res)) {
+ error = PTR_ERR(res);
+ *name = buf;
+ goto out;
+ }
+ } else if (!our_mnt(path->mnt))
+ connected = 0;
+
+ *name = res;
+
+ if (!connected)
+ error = disconnect(path, buf, name, flags, disconnected);
+
+ /* Handle two cases:
+ * 1. A deleted dentry && profile is not allowing mediation of deleted
+ * 2. On some filesystems, newly allocated dentries appear to the
+ * security_path hooks as a deleted dentry except without an inode
+ * allocated.
+ */
+ if (d_unlinked(path->dentry) && d_is_positive(path->dentry) &&
+ !(flags & (PATH_MEDIATE_DELETED | PATH_DELEGATE_DELETED))) {
+ error = -ENOENT;
+ goto out;
+ }
+
+out:
+ /* Append "/" to directory paths and reterminate string, except for
+ * root "/" which already ends in a slash.
+ */
+ if (!error && isdir) {
+ bool is_root = (*name)[0] == '/' && (*name)[1] == '\0';
+
+ if (!is_root) {
+ buf[aa_g_path_max - 2] = '/';
+ buf[aa_g_path_max - 1] = '\0';
+ }
+ }
+
+ return error;
+}
+
+/**
+ * aa_path_name - get the pathname to a buffer ensure dir / is appended
+ * @path: path the file (NOT NULL)
+ * @flags: flags controlling path name generation
+ * @buffer: buffer to put name in (NOT NULL)
+ * @name: Returns - the generated path name if !error (NOT NULL)
+ * @info: Returns - information on why the path lookup failed (MAYBE NULL)
+ * @disconnected: string to prepend to disconnected paths
+ *
+ * @name is a pointer to the beginning of the pathname (which usually differs
+ * from the beginning of the buffer), or NULL. If there is an error @name
+ * may contain a partial or invalid name that can be used for audit purposes,
+ * but it can not be used for mediation.
+ *
+ * We need PATH_IS_DIR to indicate whether the file is a directory or not
+ * because the file may not yet exist, and so we cannot check the inode's
+ * file type.
+ *
+ * Returns: %0 else error code if could retrieve name
+ */
+int aa_path_name(const struct path *path, int flags, char *buffer,
+ const char **name, const char **info, const char *disconnected)
+{
+ char *str = NULL;
+ int error = d_namespace_path(path, buffer, &str, flags, disconnected);
+
+ if (info && error) {
+ if (error == -ENOENT)
+ *info = "Failed name lookup - deleted entry";
+ else if (error == -EACCES)
+ *info = "Failed name lookup - disconnected path";
+ else if (error == -ENAMETOOLONG)
+ *info = "Failed name lookup - name too long";
+ else
+ *info = "Failed name lookup";
+ }
+
+ *name = str;
+
+ return error;
+}