kernel_samsung_a53x/fs/susfs.c
2025-01-18 21:48:58 +01:00

898 lines
31 KiB
C

#include <linux/version.h>
#include <linux/cred.h>
#include <linux/fs.h>
#include <linux/slab.h>
#include <linux/seq_file.h>
#include <linux/printk.h>
#include <linux/namei.h>
#include <linux/list.h>
#include <linux/init_task.h>
#include <linux/spinlock.h>
#include <linux/stat.h>
#include <linux/uaccess.h>
#include <linux/version.h>
#include <linux/fdtable.h>
#include <linux/statfs.h>
#include <linux/susfs.h>
#if LINUX_VERSION_CODE < KERNEL_VERSION(5,15,0)
#include "pnode.h"
#endif
static spinlock_t susfs_spin_lock;
extern bool susfs_is_current_ksu_domain(void);
#ifdef CONFIG_KSU_SUSFS_SUS_MOUNT
extern void ksu_try_umount(const char *mnt, bool check_mnt, int flags);
#endif
#ifdef CONFIG_KSU_SUSFS_ENABLE_LOG
bool susfs_is_log_enabled __read_mostly = true;
#define SUSFS_LOGI(fmt, ...) if (susfs_is_log_enabled) pr_info("susfs:[%u][%d][%s] " fmt, current_uid().val, current->pid, __func__, ##__VA_ARGS__)
#define SUSFS_LOGE(fmt, ...) if (susfs_is_log_enabled) pr_err("susfs:[%u][%d][%s]" fmt, current_uid().val, current->pid, __func__, ##__VA_ARGS__)
#else
#define SUSFS_LOGI(fmt, ...)
#define SUSFS_LOGE(fmt, ...)
#endif
/* sus_path */
#ifdef CONFIG_KSU_SUSFS_SUS_PATH
static DEFINE_HASHTABLE(SUS_PATH_HLIST, 10);
static int susfs_update_sus_path_inode(char *target_pathname) {
struct path p;
struct inode *inode = NULL;
const char *dev_type;
if (kern_path(target_pathname, LOOKUP_FOLLOW, &p)) {
SUSFS_LOGE("Failed opening file '%s'\n", target_pathname);
return 1;
}
// - We don't allow paths of which filesystem type is "tmpfs" or "fuse".
// For tmpfs, because its starting inode->i_ino will begin with 1 again,
// so it will cause wrong comparison in function susfs_sus_ino_for_filldir64()
// For fuse, which is almost storage related, sus_path should not handle any paths of
// which filesystem is "fuse" as well, since app can write to "fuse" and lookup files via
// like binder / system API (you can see the uid is changed to 1000)/
// - so sus_path should be applied only on read-only filesystem like "erofs" or "f2fs", but not "tmpfs" or "fuse",
// people may rely on HMA for /data isolation instead.
dev_type = p.mnt->mnt_sb->s_type->name;
if (!strcmp(dev_type, "tmpfs") ||
!strcmp(dev_type, "fuse")) {
SUSFS_LOGE("target_pathname: '%s' cannot be added since its filesystem type is '%s'\n",
target_pathname, dev_type);
path_put(&p);
return 1;
}
inode = d_inode(p.dentry);
if (!inode) {
SUSFS_LOGE("inode is NULL\n");
path_put(&p);
return 1;
}
if (!(inode->i_state & INODE_STATE_SUS_PATH)) {
spin_lock(&inode->i_lock);
inode->i_state |= INODE_STATE_SUS_PATH;
spin_unlock(&inode->i_lock);
}
path_put(&p);
return 0;
}
int susfs_add_sus_path(struct st_susfs_sus_path* __user user_info) {
struct st_susfs_sus_path info;
struct st_susfs_sus_path_hlist *new_entry, *tmp_entry;
struct hlist_node *tmp_node;
int bkt;
bool update_hlist = false;
if (copy_from_user(&info, user_info, sizeof(info))) {
SUSFS_LOGE("failed copying from userspace\n");
return 1;
}
spin_lock(&susfs_spin_lock);
hash_for_each_safe(SUS_PATH_HLIST, bkt, tmp_node, tmp_entry, node) {
if (!strcmp(tmp_entry->target_pathname, info.target_pathname)) {
hash_del(&tmp_entry->node);
kfree(tmp_entry);
update_hlist = true;
break;
}
}
spin_unlock(&susfs_spin_lock);
new_entry = kmalloc(sizeof(struct st_susfs_sus_path_hlist), GFP_KERNEL);
if (!new_entry) {
SUSFS_LOGE("no enough memory\n");
return 1;
}
new_entry->target_ino = info.target_ino;
strncpy(new_entry->target_pathname, info.target_pathname, SUSFS_MAX_LEN_PATHNAME-1);
if (susfs_update_sus_path_inode(new_entry->target_pathname)) {
kfree(new_entry);
return 1;
}
spin_lock(&susfs_spin_lock);
hash_add(SUS_PATH_HLIST, &new_entry->node, info.target_ino);
if (update_hlist) {
SUSFS_LOGI("target_ino: '%lu', target_pathname: '%s' is successfully updated to SUS_PATH_HLIST\n",
new_entry->target_ino, new_entry->target_pathname);
} else {
SUSFS_LOGI("target_ino: '%lu', target_pathname: '%s' is successfully added to SUS_PATH_HLIST\n",
new_entry->target_ino, new_entry->target_pathname);
}
spin_unlock(&susfs_spin_lock);
return 0;
}
int susfs_sus_ino_for_filldir64(unsigned long ino) {
struct st_susfs_sus_path_hlist *entry;
hash_for_each_possible(SUS_PATH_HLIST, entry, node, ino) {
if (entry->target_ino == ino)
return 1;
}
return 0;
}
#endif // #ifdef CONFIG_KSU_SUSFS_SUS_PATH
/* sus_mount */
#ifdef CONFIG_KSU_SUSFS_SUS_MOUNT
static LIST_HEAD(LH_SUS_MOUNT);
static void susfs_update_sus_mount_inode(char *target_pathname) {
struct path p;
struct inode *inode = NULL;
int err = 0;
err = kern_path(target_pathname, LOOKUP_FOLLOW, &p);
if (err) {
SUSFS_LOGE("Failed opening file '%s'\n", target_pathname);
return;
}
inode = d_inode(p.dentry);
if (!inode) {
path_put(&p);
SUSFS_LOGE("inode is NULL\n");
return;
}
if (!(inode->i_state & INODE_STATE_SUS_MOUNT)) {
spin_lock(&inode->i_lock);
inode->i_state |= INODE_STATE_SUS_MOUNT;
spin_unlock(&inode->i_lock);
}
path_put(&p);
}
int susfs_add_sus_mount(struct st_susfs_sus_mount* __user user_info) {
struct st_susfs_sus_mount_list *cursor = NULL, *temp = NULL;
struct st_susfs_sus_mount_list *new_list = NULL;
struct st_susfs_sus_mount info;
if (copy_from_user(&info, user_info, sizeof(info))) {
SUSFS_LOGE("failed copying from userspace\n");
return 1;
}
#if defined(__ARCH_WANT_STAT64) || defined(__ARCH_WANT_COMPAT_STAT64)
#ifdef CONFIG_MIPS
info.target_dev = new_decode_dev(info.target_dev);
#else
info.target_dev = huge_decode_dev(info.target_dev);
#endif /* CONFIG_MIPS */
#else
info.target_dev = old_decode_dev(info.target_dev);
#endif /* defined(__ARCH_WANT_STAT64) || defined(__ARCH_WANT_COMPAT_STAT64) */
list_for_each_entry_safe(cursor, temp, &LH_SUS_MOUNT, list) {
if (unlikely(!strcmp(cursor->info.target_pathname, info.target_pathname))) {
spin_lock(&susfs_spin_lock);
memcpy(&cursor->info, &info, sizeof(info));
susfs_update_sus_mount_inode(cursor->info.target_pathname);
SUSFS_LOGI("target_pathname: '%s', target_dev: '%lu', is successfully updated to LH_SUS_MOUNT\n",
cursor->info.target_pathname, cursor->info.target_dev);
spin_unlock(&susfs_spin_lock);
return 0;
}
}
new_list = kmalloc(sizeof(struct st_susfs_sus_mount_list), GFP_KERNEL);
if (!new_list) {
SUSFS_LOGE("no enough memory\n");
return 1;
}
memcpy(&new_list->info, &info, sizeof(info));
susfs_update_sus_mount_inode(new_list->info.target_pathname);
INIT_LIST_HEAD(&new_list->list);
spin_lock(&susfs_spin_lock);
list_add_tail(&new_list->list, &LH_SUS_MOUNT);
SUSFS_LOGI("target_pathname: '%s', target_dev: '%lu', is successfully added to LH_SUS_MOUNT\n",
new_list->info.target_pathname, new_list->info.target_dev);
spin_unlock(&susfs_spin_lock);
return 0;
}
#ifdef CONFIG_KSU_SUSFS_AUTO_ADD_SUS_BIND_MOUNT
int susfs_auto_add_sus_bind_mount(const char *pathname, struct path *path_target) {
struct inode *inode;
inode = path_target->dentry->d_inode;
if (!inode) return 1;
if (!(inode->i_state & INODE_STATE_SUS_MOUNT)) {
spin_lock(&inode->i_lock);
inode->i_state |= INODE_STATE_SUS_MOUNT;
spin_unlock(&inode->i_lock);
SUSFS_LOGI("set SUS_MOUNT inode state for source bind mount path '%s'\n", pathname);
}
return 0;
}
#endif // #ifdef CONFIG_KSU_SUSFS_AUTO_ADD_SUS_BIND_MOUNT
#ifdef CONFIG_KSU_SUSFS_AUTO_ADD_SUS_KSU_DEFAULT_MOUNT
void susfs_auto_add_sus_ksu_default_mount(const char __user *to_pathname) {
char *pathname = NULL;
struct path path;
struct inode *inode;
pathname = kmalloc(SUSFS_MAX_LEN_PATHNAME, GFP_KERNEL);
if (!pathname) {
SUSFS_LOGE("no enough memory\n");
return;
}
// Here we need to re-retrieve the struct path as we want the new struct path, not the old one
if (strncpy_from_user(pathname, to_pathname, SUSFS_MAX_LEN_PATHNAME-1) < 0) {
SUSFS_LOGE("strncpy_from_user()\n");
goto out_free_pathname;
return;
}
if ((!strncmp(pathname, "/data/adb/modules", 17) ||
!strncmp(pathname, "/debug_ramdisk", 14) ||
!strncmp(pathname, "/system", 7) ||
!strncmp(pathname, "/system_ext", 11) ||
!strncmp(pathname, "/vendor", 7) ||
!strncmp(pathname, "/product", 8) ||
!strncmp(pathname, "/odm", 4)) &&
!kern_path(pathname, LOOKUP_FOLLOW, &path)) {
goto set_inode_sus_mount;
}
goto out_free_pathname;
set_inode_sus_mount:
inode = path.dentry->d_inode;
if (!inode) {
goto out_path_put;
return;
}
if (!(inode->i_state & INODE_STATE_SUS_MOUNT)) {
spin_lock(&inode->i_lock);
inode->i_state |= INODE_STATE_SUS_MOUNT;
spin_unlock(&inode->i_lock);
SUSFS_LOGI("set SUS_MOUNT inode state for default KSU mount path '%s'\n", pathname);
}
out_path_put:
path_put(&path);
out_free_pathname:
kfree(pathname);
}
#endif // #ifdef CONFIG_KSU_SUSFS_AUTO_ADD_SUS_KSU_DEFAULT_MOUNT
#endif // #ifdef CONFIG_KSU_SUSFS_SUS_MOUNT
/* sus_kstat */
#ifdef CONFIG_KSU_SUSFS_SUS_KSTAT
static DEFINE_HASHTABLE(SUS_KSTAT_HLIST, 10);
static int susfs_update_sus_kstat_inode(char *target_pathname) {
struct path p;
struct inode *inode = NULL;
int err = 0;
err = kern_path(target_pathname, LOOKUP_FOLLOW, &p);
if (err) {
SUSFS_LOGE("Failed opening file '%s'\n", target_pathname);
return 1;
}
// We don't allow path of which filesystem type is "tmpfs", because its inode->i_ino is starting from 1 again,
// which will cause wrong comparison in function susfs_sus_ino_for_filldir64()
if (strcmp(p.mnt->mnt_sb->s_type->name, "tmpfs") == 0) {
SUSFS_LOGE("target_pathname: '%s' cannot be added since its filesystem is 'tmpfs'\n", target_pathname);
path_put(&p);
return 1;
}
inode = d_inode(p.dentry);
if (!inode) {
path_put(&p);
SUSFS_LOGE("inode is NULL\n");
return 1;
}
if (!(inode->i_state & INODE_STATE_SUS_KSTAT)) {
spin_lock(&inode->i_lock);
inode->i_state |= INODE_STATE_SUS_KSTAT;
spin_unlock(&inode->i_lock);
}
path_put(&p);
return 0;
}
int susfs_add_sus_kstat(struct st_susfs_sus_kstat* __user user_info) {
struct st_susfs_sus_kstat info;
struct st_susfs_sus_kstat_hlist *new_entry, *tmp_entry;
struct hlist_node *tmp_node;
int bkt;
bool update_hlist = false;
if (copy_from_user(&info, user_info, sizeof(info))) {
SUSFS_LOGE("failed copying from userspace\n");
return 1;
}
if (strlen(info.target_pathname) == 0) {
SUSFS_LOGE("target_pathname is an empty string\n");
return 1;
}
spin_lock(&susfs_spin_lock);
hash_for_each_safe(SUS_KSTAT_HLIST, bkt, tmp_node, tmp_entry, node) {
if (!strcmp(tmp_entry->info.target_pathname, info.target_pathname)) {
hash_del(&tmp_entry->node);
kfree(tmp_entry);
update_hlist = true;
break;
}
}
spin_unlock(&susfs_spin_lock);
new_entry = kmalloc(sizeof(struct st_susfs_sus_kstat_hlist), GFP_KERNEL);
if (!new_entry) {
SUSFS_LOGE("no enough memory\n");
return 1;
}
#if defined(__ARCH_WANT_STAT64) || defined(__ARCH_WANT_COMPAT_STAT64)
#ifdef CONFIG_MIPS
info.spoofed_dev = new_decode_dev(info.spoofed_dev);
#else
info.spoofed_dev = huge_decode_dev(info.spoofed_dev);
#endif /* CONFIG_MIPS */
#else
info.spoofed_dev = old_decode_dev(info.spoofed_dev);
#endif /* defined(__ARCH_WANT_STAT64) || defined(__ARCH_WANT_COMPAT_STAT64) */
new_entry->target_ino = info.target_ino;
memcpy(&new_entry->info, &info, sizeof(info));
if (susfs_update_sus_kstat_inode(new_entry->info.target_pathname)) {
kfree(new_entry);
return 1;
}
spin_lock(&susfs_spin_lock);
hash_add(SUS_KSTAT_HLIST, &new_entry->node, info.target_ino);
#if LINUX_VERSION_CODE >= KERNEL_VERSION(6, 1, 0)
if (update_hlist) {
SUSFS_LOGI("is_statically: '%d', target_ino: '%lu', target_pathname: '%s', spoofed_ino: '%lu', spoofed_dev: '%lu', spoofed_nlink: '%u', spoofed_size: '%llu', spoofed_atime_tv_sec: '%ld', spoofed_mtime_tv_sec: '%ld', spoofed_ctime_tv_sec: '%ld', spoofed_atime_tv_nsec: '%ld', spoofed_mtime_tv_nsec: '%ld', spoofed_ctime_tv_nsec: '%ld', spoofed_blksize: '%lu', spoofed_blocks: '%llu', is successfully added to SUS_KSTAT_HLIST\n",
new_entry->info.is_statically, new_entry->info.target_ino, new_entry->info.target_pathname,
new_entry->info.spoofed_ino, new_entry->info.spoofed_dev,
new_entry->info.spoofed_nlink, new_entry->info.spoofed_size,
new_entry->info.spoofed_atime_tv_sec, new_entry->info.spoofed_mtime_tv_sec, new_entry->info.spoofed_ctime_tv_sec,
new_entry->info.spoofed_atime_tv_nsec, new_entry->info.spoofed_mtime_tv_nsec, new_entry->info.spoofed_ctime_tv_nsec,
new_entry->info.spoofed_blksize, new_entry->info.spoofed_blocks);
} else {
SUSFS_LOGI("is_statically: '%d', target_ino: '%lu', target_pathname: '%s', spoofed_ino: '%lu', spoofed_dev: '%lu', spoofed_nlink: '%u', spoofed_size: '%llu', spoofed_atime_tv_sec: '%ld', spoofed_mtime_tv_sec: '%ld', spoofed_ctime_tv_sec: '%ld', spoofed_atime_tv_nsec: '%ld', spoofed_mtime_tv_nsec: '%ld', spoofed_ctime_tv_nsec: '%ld', spoofed_blksize: '%lu', spoofed_blocks: '%llu', is successfully updated to SUS_KSTAT_HLIST\n",
new_entry->info.is_statically, new_entry->info.target_ino, new_entry->info.target_pathname,
new_entry->info.spoofed_ino, new_entry->info.spoofed_dev,
new_entry->info.spoofed_nlink, new_entry->info.spoofed_size,
new_entry->info.spoofed_atime_tv_sec, new_entry->info.spoofed_mtime_tv_sec, new_entry->info.spoofed_ctime_tv_sec,
new_entry->info.spoofed_atime_tv_nsec, new_entry->info.spoofed_mtime_tv_nsec, new_entry->info.spoofed_ctime_tv_nsec,
new_entry->info.spoofed_blksize, new_entry->info.spoofed_blocks);
}
#else
if (update_hlist) {
SUSFS_LOGI("is_statically: '%d', target_ino: '%lu', target_pathname: '%s', spoofed_ino: '%lu', spoofed_dev: '%lu', spoofed_nlink: '%u', spoofed_size: '%u', spoofed_atime_tv_sec: '%ld', spoofed_mtime_tv_sec: '%ld', spoofed_ctime_tv_sec: '%ld', spoofed_atime_tv_nsec: '%ld', spoofed_mtime_tv_nsec: '%ld', spoofed_ctime_tv_nsec: '%ld', spoofed_blksize: '%lu', spoofed_blocks: '%llu', is successfully added to SUS_KSTAT_HLIST\n",
new_entry->info.is_statically, new_entry->info.target_ino, new_entry->info.target_pathname,
new_entry->info.spoofed_ino, new_entry->info.spoofed_dev,
new_entry->info.spoofed_nlink, new_entry->info.spoofed_size,
new_entry->info.spoofed_atime_tv_sec, new_entry->info.spoofed_mtime_tv_sec, new_entry->info.spoofed_ctime_tv_sec,
new_entry->info.spoofed_atime_tv_nsec, new_entry->info.spoofed_mtime_tv_nsec, new_entry->info.spoofed_ctime_tv_nsec,
new_entry->info.spoofed_blksize, new_entry->info.spoofed_blocks);
} else {
SUSFS_LOGI("is_statically: '%d', target_ino: '%lu', target_pathname: '%s', spoofed_ino: '%lu', spoofed_dev: '%lu', spoofed_nlink: '%u', spoofed_size: '%u', spoofed_atime_tv_sec: '%ld', spoofed_mtime_tv_sec: '%ld', spoofed_ctime_tv_sec: '%ld', spoofed_atime_tv_nsec: '%ld', spoofed_mtime_tv_nsec: '%ld', spoofed_ctime_tv_nsec: '%ld', spoofed_blksize: '%lu', spoofed_blocks: '%llu', is successfully updated to SUS_KSTAT_HLIST\n",
new_entry->info.is_statically, new_entry->info.target_ino, new_entry->info.target_pathname,
new_entry->info.spoofed_ino, new_entry->info.spoofed_dev,
new_entry->info.spoofed_nlink, new_entry->info.spoofed_size,
new_entry->info.spoofed_atime_tv_sec, new_entry->info.spoofed_mtime_tv_sec, new_entry->info.spoofed_ctime_tv_sec,
new_entry->info.spoofed_atime_tv_nsec, new_entry->info.spoofed_mtime_tv_nsec, new_entry->info.spoofed_ctime_tv_nsec,
new_entry->info.spoofed_blksize, new_entry->info.spoofed_blocks);
}
#endif
spin_unlock(&susfs_spin_lock);
return 0;
}
int susfs_update_sus_kstat(struct st_susfs_sus_kstat* __user user_info) {
struct st_susfs_sus_kstat info;
struct st_susfs_sus_kstat_hlist *new_entry, *tmp_entry;
struct hlist_node *tmp_node;
int bkt;
int err = 0;
if (copy_from_user(&info, user_info, sizeof(info))) {
SUSFS_LOGE("failed copying from userspace\n");
return 1;
}
spin_lock(&susfs_spin_lock);
hash_for_each_safe(SUS_KSTAT_HLIST, bkt, tmp_node, tmp_entry, node) {
if (!strcmp(tmp_entry->info.target_pathname, info.target_pathname)) {
if (susfs_update_sus_kstat_inode(tmp_entry->info.target_pathname)) {
err = 1;
goto out_spin_unlock;
}
new_entry = kmalloc(sizeof(struct st_susfs_sus_kstat_hlist), GFP_KERNEL);
if (!new_entry) {
SUSFS_LOGE("no enough memory\n");
err = 1;
goto out_spin_unlock;
}
memcpy(&new_entry->info, &tmp_entry->info, sizeof(tmp_entry->info));
SUSFS_LOGI("updating target_ino from '%lu' to '%lu' for pathname: '%s' in SUS_KSTAT_HLIST\n",
new_entry->info.target_ino, info.target_ino, info.target_pathname);
new_entry->target_ino = info.target_ino;
new_entry->info.target_ino = info.target_ino;
if (info.spoofed_size > 0) {
SUSFS_LOGI("updating spoofed_size from '%lld' to '%lld' for pathname: '%s' in SUS_KSTAT_HLIST\n",
new_entry->info.spoofed_size, info.spoofed_size, info.target_pathname);
new_entry->info.spoofed_size = info.spoofed_size;
}
if (info.spoofed_blocks > 0) {
SUSFS_LOGI("updating spoofed_blocks from '%llu' to '%llu' for pathname: '%s' in SUS_KSTAT_HLIST\n",
new_entry->info.spoofed_blocks, info.spoofed_blocks, info.target_pathname);
new_entry->info.spoofed_blocks = info.spoofed_blocks;
}
hash_del(&tmp_entry->node);
kfree(tmp_entry);
hash_add(SUS_KSTAT_HLIST, &new_entry->node, info.target_ino);
goto out_spin_unlock;
}
}
out_spin_unlock:
spin_unlock(&susfs_spin_lock);
return err;
}
void susfs_sus_ino_for_generic_fillattr(unsigned long ino, struct kstat *stat) {
struct st_susfs_sus_kstat_hlist *entry;
hash_for_each_possible(SUS_KSTAT_HLIST, entry, node, ino) {
if (entry->target_ino == ino) {
stat->dev = entry->info.spoofed_dev;
stat->ino = entry->info.spoofed_ino;
stat->nlink = entry->info.spoofed_nlink;
stat->size = entry->info.spoofed_size;
stat->atime.tv_sec = entry->info.spoofed_atime_tv_sec;
stat->atime.tv_nsec = entry->info.spoofed_atime_tv_nsec;
stat->mtime.tv_sec = entry->info.spoofed_mtime_tv_sec;
stat->mtime.tv_nsec = entry->info.spoofed_mtime_tv_nsec;
stat->ctime.tv_sec = entry->info.spoofed_ctime_tv_sec;
stat->ctime.tv_nsec = entry->info.spoofed_ctime_tv_nsec;
stat->blocks = entry->info.spoofed_blocks;
stat->blksize = entry->info.spoofed_blksize;
return;
}
}
}
void susfs_sus_ino_for_show_map_vma(unsigned long ino, dev_t *out_dev, unsigned long *out_ino) {
struct st_susfs_sus_kstat_hlist *entry;
hash_for_each_possible(SUS_KSTAT_HLIST, entry, node, ino) {
if (entry->target_ino == ino) {
*out_dev = entry->info.spoofed_dev;
*out_ino = entry->info.spoofed_ino;
return;
}
}
}
#endif // #ifdef CONFIG_KSU_SUSFS_SUS_KSTAT
/* try_umount */
#ifdef CONFIG_KSU_SUSFS_TRY_UMOUNT
static LIST_HEAD(LH_TRY_UMOUNT_PATH);
int susfs_add_try_umount(struct st_susfs_try_umount* __user user_info) {
struct st_susfs_try_umount_list *cursor = NULL, *temp = NULL;
struct st_susfs_try_umount_list *new_list = NULL;
struct st_susfs_try_umount info;
if (copy_from_user(&info, user_info, sizeof(info))) {
SUSFS_LOGE("failed copying from userspace\n");
return 1;
}
list_for_each_entry_safe(cursor, temp, &LH_TRY_UMOUNT_PATH, list) {
if (unlikely(!strcmp(info.target_pathname, cursor->info.target_pathname))) {
SUSFS_LOGE("target_pathname: '%s' is already created in LH_TRY_UMOUNT_PATH\n", info.target_pathname);
return 1;
}
}
new_list = kmalloc(sizeof(struct st_susfs_try_umount_list), GFP_KERNEL);
if (!new_list) {
SUSFS_LOGE("no enough memory\n");
return 1;
}
memcpy(&new_list->info, &info, sizeof(info));
INIT_LIST_HEAD(&new_list->list);
spin_lock(&susfs_spin_lock);
list_add_tail(&new_list->list, &LH_TRY_UMOUNT_PATH);
spin_unlock(&susfs_spin_lock);
SUSFS_LOGI("target_pathname: '%s', mnt_mode: %d, is successfully added to LH_TRY_UMOUNT_PATH\n", new_list->info.target_pathname, new_list->info.mnt_mode);
return 0;
}
void susfs_try_umount(uid_t target_uid) {
struct st_susfs_try_umount_list *cursor = NULL;
// We should umount in reversed order
list_for_each_entry_reverse(cursor, &LH_TRY_UMOUNT_PATH, list) {
SUSFS_LOGI("umounting '%s' for uid: %d\n", cursor->info.target_pathname, target_uid);
if (cursor->info.mnt_mode == TRY_UMOUNT_DEFAULT) {
ksu_try_umount(cursor->info.target_pathname, false, 0);
} else if (cursor->info.mnt_mode == TRY_UMOUNT_DETACH) {
ksu_try_umount(cursor->info.target_pathname, false, MNT_DETACH);
} else {
SUSFS_LOGE("failed umounting '%s' for uid: %d, mnt_mode '%d' not supported\n",
cursor->info.target_pathname, target_uid, cursor->info.mnt_mode);
}
}
}
#ifdef CONFIG_KSU_SUSFS_AUTO_ADD_TRY_UMOUNT_FOR_BIND_MOUNT
void susfs_auto_add_try_umount_for_bind_mount(struct path *path) {
struct st_susfs_try_umount_list *cursor = NULL, *temp = NULL;
struct st_susfs_try_umount_list *new_list = NULL;
char *pathname = NULL, *dpath = NULL;
#ifdef CONFIG_KSU_SUSFS_HAS_MAGIC_MOUNT
bool is_magic_mount_path = false;
#endif
#ifdef CONFIG_KSU_SUSFS_SUS_KSTAT
if (path->dentry->d_inode->i_state & INODE_STATE_SUS_KSTAT) {
SUSFS_LOGI("skip adding path to try_umount list as its inode is flagged INODE_STATE_SUS_KSTAT already\n");
return;
}
#endif
pathname = kmalloc(PAGE_SIZE, GFP_KERNEL);
if (!pathname) {
SUSFS_LOGE("no enough memory\n");
return;
}
dpath = d_path(path, pathname, PAGE_SIZE);
if (!dpath) {
SUSFS_LOGE("dpath is NULL\n");
goto out_free_pathname;
}
#ifdef CONFIG_KSU_SUSFS_HAS_MAGIC_MOUNT
if (strstr(dpath, MAGIC_MOUNT_WORKDIR)) {
is_magic_mount_path = true;
}
#endif
list_for_each_entry_safe(cursor, temp, &LH_TRY_UMOUNT_PATH, list) {
#ifdef CONFIG_KSU_SUSFS_HAS_MAGIC_MOUNT
if (is_magic_mount_path && strstr(dpath, cursor->info.target_pathname)) {
goto out_free_pathname;
}
#endif
if (unlikely(!strcmp(dpath, cursor->info.target_pathname))) {
SUSFS_LOGE("target_pathname: '%s', ino: %lu, is already created in LH_TRY_UMOUNT_PATH\n",
dpath, path->dentry->d_inode->i_ino);
goto out_free_pathname;
}
}
new_list = kmalloc(sizeof(struct st_susfs_try_umount_list), GFP_KERNEL);
if (!new_list) {
SUSFS_LOGE("no enough memory\n");
goto out_free_pathname;
}
#ifdef CONFIG_KSU_SUSFS_HAS_MAGIC_MOUNT
if (is_magic_mount_path) {
strncpy(new_list->info.target_pathname, dpath + strlen(MAGIC_MOUNT_WORKDIR), SUSFS_MAX_LEN_PATHNAME-1);
goto out_add_to_list;
}
#endif
strncpy(new_list->info.target_pathname, dpath, SUSFS_MAX_LEN_PATHNAME-1);
#ifdef CONFIG_KSU_SUSFS_HAS_MAGIC_MOUNT
out_add_to_list:
#endif
new_list->info.mnt_mode = TRY_UMOUNT_DETACH;
INIT_LIST_HEAD(&new_list->list);
spin_lock(&susfs_spin_lock);
list_add_tail(&new_list->list, &LH_TRY_UMOUNT_PATH);
spin_unlock(&susfs_spin_lock);
SUSFS_LOGI("target_pathname: '%s', ino: %lu, mnt_mode: %d, is successfully added to LH_TRY_UMOUNT_PATH\n",
new_list->info.target_pathname, path->dentry->d_inode->i_ino, new_list->info.mnt_mode);
out_free_pathname:
kfree(pathname);
}
#endif // #ifdef CONFIG_KSU_SUSFS_AUTO_ADD_TRY_UMOUNT_FOR_BIND_MOUNT
#endif // #ifdef CONFIG_KSU_SUSFS_TRY_UMOUNT
/* spoof_uname */
#ifdef CONFIG_KSU_SUSFS_SPOOF_UNAME
static spinlock_t susfs_uname_spin_lock;
static struct st_susfs_uname my_uname;
static void susfs_my_uname_init(void) {
memset(&my_uname, 0, sizeof(my_uname));
}
int susfs_set_uname(struct st_susfs_uname* __user user_info) {
struct st_susfs_uname info;
if (copy_from_user(&info, user_info, sizeof(struct st_susfs_uname))) {
SUSFS_LOGE("failed copying from userspace.\n");
return 1;
}
spin_lock(&susfs_uname_spin_lock);
if (!strcmp(info.release, "default")) {
strncpy(my_uname.release, utsname()->release, __NEW_UTS_LEN);
} else {
strncpy(my_uname.release, info.release, __NEW_UTS_LEN);
}
if (!strcmp(info.version, "default")) {
strncpy(my_uname.version, utsname()->version, __NEW_UTS_LEN);
} else {
strncpy(my_uname.version, info.version, __NEW_UTS_LEN);
}
spin_unlock(&susfs_uname_spin_lock);
SUSFS_LOGI("setting spoofed release: '%s', version: '%s'\n",
my_uname.release, my_uname.version);
return 0;
}
void susfs_spoof_uname(struct new_utsname* tmp) {
if (unlikely(my_uname.release[0] == '\0' || spin_is_locked(&susfs_uname_spin_lock)))
return;
strncpy(tmp->release, my_uname.release, __NEW_UTS_LEN);
strncpy(tmp->version, my_uname.version, __NEW_UTS_LEN);
}
#endif // #ifdef CONFIG_KSU_SUSFS_SPOOF_UNAME
/* set_log */
#ifdef CONFIG_KSU_SUSFS_ENABLE_LOG
void susfs_set_log(bool enabled) {
spin_lock(&susfs_spin_lock);
susfs_is_log_enabled = enabled;
spin_unlock(&susfs_spin_lock);
if (susfs_is_log_enabled) {
pr_info("susfs: enable logging to kernel");
} else {
pr_info("susfs: disable logging to kernel");
}
}
#endif // #ifdef CONFIG_KSU_SUSFS_ENABLE_LOG
/* spoof_cmdline_or_bootconfig */
#ifdef CONFIG_KSU_SUSFS_SPOOF_CMDLINE_OR_BOOTCONFIG
static char *fake_cmdline_or_bootconfig = NULL;
int susfs_set_cmdline_or_bootconfig(char* __user user_fake_cmdline_or_bootconfig) {
int res;
if (!fake_cmdline_or_bootconfig) {
// 4096 is enough I guess
fake_cmdline_or_bootconfig = kmalloc(SUSFS_FAKE_CMDLINE_OR_BOOTCONFIG_SIZE, GFP_KERNEL);
if (!fake_cmdline_or_bootconfig) {
SUSFS_LOGE("no enough memory\n");
return -ENOMEM;
}
}
spin_lock(&susfs_spin_lock);
memset(fake_cmdline_or_bootconfig, 0, SUSFS_FAKE_CMDLINE_OR_BOOTCONFIG_SIZE);
res = strncpy_from_user(fake_cmdline_or_bootconfig, user_fake_cmdline_or_bootconfig, SUSFS_FAKE_CMDLINE_OR_BOOTCONFIG_SIZE-1);
spin_unlock(&susfs_spin_lock);
if (res > 0) {
#if LINUX_VERSION_CODE >= KERNEL_VERSION(6,1,0)
SUSFS_LOGI("fake_cmdline_or_bootconfig is set, length of string: %lu\n", strlen(fake_cmdline_or_bootconfig));
#else
SUSFS_LOGI("fake_cmdline_or_bootconfig is set, length of string: %u\n", strlen(fake_cmdline_or_bootconfig));
#endif
return 0;
}
SUSFS_LOGI("failed setting fake_cmdline_or_bootconfig\n");
return res;
}
int susfs_spoof_cmdline_or_bootconfig(struct seq_file *m) {
if (fake_cmdline_or_bootconfig != NULL) {
seq_puts(m, fake_cmdline_or_bootconfig);
return 0;
}
return 1;
}
#endif
/* open_redirect */
#ifdef CONFIG_KSU_SUSFS_OPEN_REDIRECT
static DEFINE_HASHTABLE(OPEN_REDIRECT_HLIST, 10);
static int susfs_update_open_redirect_inode(struct st_susfs_open_redirect_hlist *new_entry) {
struct path path_target;
struct inode *inode_target;
int err = 0;
err = kern_path(new_entry->target_pathname, LOOKUP_FOLLOW, &path_target);
if (err) {
SUSFS_LOGE("Failed opening file '%s'\n", new_entry->target_pathname);
return err;
}
inode_target = d_inode(path_target.dentry);
if (!inode_target) {
SUSFS_LOGE("inode_target is NULL\n");
err = 1;
goto out_path_put_target;
}
spin_lock(&inode_target->i_lock);
inode_target->i_state |= INODE_STATE_OPEN_REDIRECT;
spin_unlock(&inode_target->i_lock);
out_path_put_target:
path_put(&path_target);
return err;
}
int susfs_add_open_redirect(struct st_susfs_open_redirect* __user user_info) {
struct st_susfs_open_redirect info;
struct st_susfs_open_redirect_hlist *new_entry, *tmp_entry;
struct hlist_node *tmp_node;
int bkt;
bool update_hlist = false;
if (copy_from_user(&info, user_info, sizeof(info))) {
SUSFS_LOGE("failed copying from userspace\n");
return 1;
}
spin_lock(&susfs_spin_lock);
hash_for_each_safe(OPEN_REDIRECT_HLIST, bkt, tmp_node, tmp_entry, node) {
if (!strcmp(tmp_entry->target_pathname, info.target_pathname)) {
hash_del(&tmp_entry->node);
kfree(tmp_entry);
update_hlist = true;
break;
}
}
spin_unlock(&susfs_spin_lock);
new_entry = kmalloc(sizeof(struct st_susfs_open_redirect_hlist), GFP_KERNEL);
if (!new_entry) {
SUSFS_LOGE("no enough memory\n");
return 1;
}
new_entry->target_ino = info.target_ino;
strncpy(new_entry->target_pathname, info.target_pathname, SUSFS_MAX_LEN_PATHNAME-1);
strncpy(new_entry->redirected_pathname, info.redirected_pathname, SUSFS_MAX_LEN_PATHNAME-1);
if (susfs_update_open_redirect_inode(new_entry)) {
SUSFS_LOGE("failed adding path '%s' to OPEN_REDIRECT_HLIST\n", new_entry->target_pathname);
kfree(new_entry);
return 1;
}
spin_lock(&susfs_spin_lock);
hash_add(OPEN_REDIRECT_HLIST, &new_entry->node, info.target_ino);
if (update_hlist) {
SUSFS_LOGI("target_ino: '%lu', target_pathname: '%s', redirected_pathname: '%s', is successfully updated to OPEN_REDIRECT_HLIST\n",
new_entry->target_ino, new_entry->target_pathname, new_entry->redirected_pathname);
} else {
SUSFS_LOGI("target_ino: '%lu', target_pathname: '%s' redirected_pathname: '%s', is successfully added to OPEN_REDIRECT_HLIST\n",
new_entry->target_ino, new_entry->target_pathname, new_entry->redirected_pathname);
}
spin_unlock(&susfs_spin_lock);
return 0;
}
struct filename* susfs_get_redirected_path(unsigned long ino) {
struct st_susfs_open_redirect_hlist *entry;
hash_for_each_possible(OPEN_REDIRECT_HLIST, entry, node, ino) {
if (entry->target_ino == ino) {
SUSFS_LOGI("Redirect for ino: %lu\n", ino);
return getname_kernel(entry->redirected_pathname);
}
}
return ERR_PTR(-ENOENT);
}
#endif // #ifdef CONFIG_KSU_SUSFS_OPEN_REDIRECT
/* sus_su */
#ifdef CONFIG_KSU_SUSFS_SUS_SU
bool susfs_is_sus_su_hooks_enabled __read_mostly = false;
static int susfs_sus_su_working_mode = 0;
extern void ksu_susfs_enable_sus_su(void);
extern void ksu_susfs_disable_sus_su(void);
int susfs_get_sus_su_working_mode(void) {
return susfs_sus_su_working_mode;
}
int susfs_sus_su(struct st_sus_su* __user user_info) {
struct st_sus_su info;
int last_working_mode = susfs_sus_su_working_mode;
if (copy_from_user(&info, user_info, sizeof(struct st_sus_su))) {
SUSFS_LOGE("failed copying from userspace\n");
return 1;
}
if (info.mode == SUS_SU_WITH_HOOKS) {
if (last_working_mode == SUS_SU_WITH_HOOKS) {
SUSFS_LOGE("current sus_su mode is already %d\n", SUS_SU_WITH_HOOKS);
return 1;
}
if (last_working_mode != SUS_SU_DISABLED) {
SUSFS_LOGE("please make sure the current sus_su mode is %d first\n", SUS_SU_DISABLED);
return 2;
}
ksu_susfs_enable_sus_su();
susfs_sus_su_working_mode = SUS_SU_WITH_HOOKS;
susfs_is_sus_su_hooks_enabled = true;
SUSFS_LOGI("core kprobe hooks for ksu are disabled!\n");
SUSFS_LOGI("non-kprobe hook sus_su is enabled!\n");
SUSFS_LOGI("sus_su mode: %d\n", SUS_SU_WITH_HOOKS);
return 0;
} else if (info.mode == SUS_SU_DISABLED) {
if (last_working_mode == SUS_SU_DISABLED) {
SUSFS_LOGE("current sus_su mode is already %d\n", SUS_SU_DISABLED);
return 1;
}
susfs_is_sus_su_hooks_enabled = false;
ksu_susfs_disable_sus_su();
susfs_sus_su_working_mode = SUS_SU_DISABLED;
if (last_working_mode == SUS_SU_WITH_HOOKS) {
SUSFS_LOGI("core kprobe hooks for ksu are enabled!\n");
goto out;
}
out:
if (copy_to_user(user_info, &info, sizeof(info)))
SUSFS_LOGE("copy_to_user() failed\n");
return 0;
} else if (info.mode == SUS_SU_WITH_OVERLAY) {
SUSFS_LOGE("sus_su mode %d is deprecated\n", SUS_SU_WITH_OVERLAY);
return 1;
}
return 1;
}
#endif // #ifdef CONFIG_KSU_SUSFS_SUS_SU
/* susfs_init */
void susfs_init(void) {
spin_lock_init(&susfs_spin_lock);
#ifdef CONFIG_KSU_SUSFS_SPOOF_UNAME
spin_lock_init(&susfs_uname_spin_lock);
susfs_my_uname_init();
#endif
SUSFS_LOGI("susfs is initialized! version: " SUSFS_VERSION " \n");
}
/* No module exit is needed becuase it should never be a loadable kernel module */
//void __init susfs_exit(void)