From 4352b8aee98005853aa63f57d6377282de17a33f Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 23 Aug 2026 13:28:57 -0700 Subject: Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux 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 ... --- security/tomoyo/realpath.c | 310 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 310 insertions(+) create mode 100644 security/tomoyo/realpath.c (limited to 'security/tomoyo/realpath.c') diff --git a/security/tomoyo/realpath.c b/security/tomoyo/realpath.c new file mode 100644 index 000000000..1c483ee7f --- /dev/null +++ b/security/tomoyo/realpath.c @@ -0,0 +1,310 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * security/tomoyo/realpath.c + * + * Copyright (C) 2005-2011 NTT DATA CORPORATION + */ + +#include "common.h" +#include +#include + +/** + * tomoyo_encode2 - Encode binary string to ascii string. + * + * @str: String in binary format. + * @str_len: Size of @str in byte. + * + * Returns pointer to @str in ascii format on success, NULL otherwise. + * + * This function uses kzalloc(), so caller must kfree() if this function + * didn't return NULL. + */ +char *tomoyo_encode2(const char *str, int str_len) +{ + int i; + int len = 0; + const char *p = str; + char *cp; + char *cp0; + + if (!p) + return NULL; + for (i = 0; i < str_len; i++) { + const unsigned char c = p[i]; + + if (c == '\\') + len += 2; + else if (c > ' ' && c < 127) + len++; + else + len += 4; + } + len++; + /* Reserve space for appending "/". */ + cp = kzalloc(len + 10, GFP_NOFS); + if (!cp) + return NULL; + cp0 = cp; + p = str; + for (i = 0; i < str_len; i++) { + const unsigned char c = p[i]; + + if (c == '\\') { + *cp++ = '\\'; + *cp++ = '\\'; + } else if (c > ' ' && c < 127) { + *cp++ = c; + } else { + *cp++ = '\\'; + *cp++ = (c >> 6) + '0'; + *cp++ = ((c >> 3) & 7) + '0'; + *cp++ = (c & 7) + '0'; + } + } + return cp0; +} + +/** + * tomoyo_encode - Encode binary string to ascii string. + * + * @str: String in binary format. + * + * Returns pointer to @str in ascii format on success, NULL otherwise. + * + * This function uses kzalloc(), so caller must kfree() if this function + * didn't return NULL. + */ +char *tomoyo_encode(const char *str) +{ + return str ? tomoyo_encode2(str, strlen(str)) : NULL; +} + +/** + * tomoyo_get_absolute_path - Get the path of a dentry but ignores chroot'ed root. + * + * @path: Pointer to "struct path". + * @buffer: Pointer to buffer to return value in. + * @buflen: Sizeof @buffer. + * + * Returns the buffer on success, an error code otherwise. + * + * If dentry is a directory, trailing '/' is appended. + */ +static char *tomoyo_get_absolute_path(const struct path *path, char * const buffer, + const int buflen) +{ + char *pos = ERR_PTR(-ENOMEM); + + if (buflen >= 256) { + /* go to whatever namespace root we are under */ + pos = d_absolute_path(path, buffer, buflen - 1); + if (!IS_ERR(pos) && *pos == '/' && pos[1]) { + struct inode *inode = d_backing_inode(path->dentry); + + if (inode && S_ISDIR(inode->i_mode)) { + buffer[buflen - 2] = '/'; + buffer[buflen - 1] = '\0'; + } + } + } + return pos; +} + +/** + * tomoyo_get_dentry_path - Get the path of a dentry. + * + * @dentry: Pointer to "struct dentry". + * @buffer: Pointer to buffer to return value in. + * @buflen: Sizeof @buffer. + * + * Returns the buffer on success, an error code otherwise. + * + * If dentry is a directory, trailing '/' is appended. + */ +static char *tomoyo_get_dentry_path(struct dentry *dentry, char * const buffer, + const int buflen) +{ + char *pos = ERR_PTR(-ENOMEM); + + if (buflen >= 256) { + pos = dentry_path_raw(dentry, buffer, buflen - 1); + if (!IS_ERR(pos) && *pos == '/' && pos[1]) { + struct inode *inode = d_backing_inode(dentry); + + if (inode && S_ISDIR(inode->i_mode)) { + buffer[buflen - 2] = '/'; + buffer[buflen - 1] = '\0'; + } + } + } + return pos; +} + +/** + * tomoyo_get_local_path - Get the path of a dentry. + * + * @dentry: Pointer to "struct dentry". + * @buffer: Pointer to buffer to return value in. + * @buflen: Sizeof @buffer. + * + * Returns the buffer on success, an error code otherwise. + */ +static char *tomoyo_get_local_path(struct dentry *dentry, char * const buffer, + const int buflen) +{ + struct super_block *sb = dentry->d_sb; + char *pos = tomoyo_get_dentry_path(dentry, buffer, buflen); + + if (IS_ERR(pos)) + return pos; + /* Convert from $PID to self if $PID is current thread. */ + if (sb->s_magic == PROC_SUPER_MAGIC && *pos == '/') { + char *ep; + const pid_t pid = (pid_t) simple_strtoul(pos + 1, &ep, 10); + struct pid_namespace *proc_pidns = proc_pid_ns(sb); + + if (*ep == '/' && pid && pid == + task_tgid_nr_ns(current, proc_pidns)) { + pos = ep - 5; + if (pos < buffer) + goto out; + memmove(pos, "/self", 5); + } + goto prepend_filesystem_name; + } + /* Use filesystem name for unnamed devices. */ + if (!MAJOR(sb->s_dev)) + goto prepend_filesystem_name; + { + struct inode *inode = d_backing_inode(sb->s_root); + + /* + * Use filesystem name if filesystem does not support rename() + * operation. + */ + if (!inode->i_op->rename) + goto prepend_filesystem_name; + } + /* Prepend device name. */ + { + char name[64]; + int name_len; + const dev_t dev = sb->s_dev; + + name[sizeof(name) - 1] = '\0'; + snprintf(name, sizeof(name) - 1, "dev(%u,%u):", MAJOR(dev), + MINOR(dev)); + name_len = strlen(name); + pos -= name_len; + if (pos < buffer) + goto out; + memmove(pos, name, name_len); + return pos; + } + /* Prepend filesystem name. */ +prepend_filesystem_name: + { + const char *name = sb->s_type->name; + const int name_len = strlen(name); + + pos -= name_len + 1; + if (pos < buffer) + goto out; + memmove(pos, name, name_len); + pos[name_len] = ':'; + } + return pos; +out: + return ERR_PTR(-ENOMEM); +} + +/** + * tomoyo_realpath_from_path - Returns realpath(3) of the given pathname but ignores chroot'ed root. + * + * @path: Pointer to "struct path". + * + * Returns the realpath of the given @path on success, NULL otherwise. + * + * If dentry is a directory, trailing '/' is appended. + * Characters out of 0x20 < c < 0x7F range are converted to + * \ooo style octal string. + * Character \ is converted to \\ string. + * + * These functions use kzalloc(), so the caller must call kfree() + * if these functions didn't return NULL. + */ +char *tomoyo_realpath_from_path(const struct path *path) +{ + char *buf = NULL; + char *name = NULL; + unsigned int buf_len = PAGE_SIZE / 2; + struct dentry *dentry = path->dentry; + struct super_block *sb = dentry->d_sb; + + while (1) { + char *pos; + struct inode *inode; + + buf_len <<= 1; + kfree(buf); + buf = kmalloc(buf_len, GFP_NOFS); + if (!buf) + break; + /* To make sure that pos is '\0' terminated. */ + buf[buf_len - 1] = '\0'; + /* For "pipe:[\$]" and "socket:[\$]". */ + if (dentry->d_op && dentry->d_op->d_dname) { + pos = dentry->d_op->d_dname(dentry, buf, buf_len - 1); + goto encode; + } + inode = d_backing_inode(sb->s_root); + /* + * Get local name for filesystems without rename() operation + */ + if ((!inode->i_op->rename && + !(sb->s_type->fs_flags & FS_REQUIRES_DEV))) + pos = tomoyo_get_local_path(path->dentry, buf, + buf_len - 1); + /* Get absolute name for the rest. */ + else { + pos = tomoyo_get_absolute_path(path, buf, buf_len - 1); + /* + * Fall back to local name if absolute name is not + * available. + */ + if (pos == ERR_PTR(-EINVAL)) + pos = tomoyo_get_local_path(path->dentry, buf, + buf_len - 1); + } +encode: + if (IS_ERR(pos)) + continue; + name = tomoyo_encode(pos); + break; + } + kfree(buf); + if (!name) + tomoyo_warn_oom(__func__); + return name; +} + +/** + * tomoyo_realpath_nofollow - Get realpath of a pathname. + * + * @pathname: The pathname to solve. + * + * Returns the realpath of @pathname on success, NULL otherwise. + */ +char *tomoyo_realpath_nofollow(const char *pathname) +{ + struct path path; + + if (pathname && kern_path(pathname, 0, &path) == 0) { + char *buf = tomoyo_realpath_from_path(&path); + + path_put(&path); + return buf; + } + return NULL; +} -- cgit v1.3.1