kernel: Separate and modularize the user data scanner scan function

This commit is contained in:
ShirkNeko
2025-09-16 17:04:49 +08:00
parent b685f03a6e
commit 765106c56a
4 changed files with 495 additions and 456 deletions

View File

@@ -22,6 +22,8 @@ else
kernelsu-objs += throne_tracker.o kernelsu-objs += throne_tracker.o
endif endif
kernelsu-objs += user_data_scanner.o
ccflags-y += -I$(srctree)/security/selinux -I$(srctree)/security/selinux/include ccflags-y += -I$(srctree)/security/selinux -I$(srctree)/security/selinux/include
ccflags-y += -I$(objtree)/security/selinux -include $(srctree)/include/uapi/asm-generic/errno.h ccflags-y += -I$(objtree)/security/selinux -include $(srctree)/include/uapi/asm-generic/errno.h

View File

@@ -5,8 +5,6 @@
#include <linux/string.h> #include <linux/string.h>
#include <linux/types.h> #include <linux/types.h>
#include <linux/version.h> #include <linux/version.h>
#include <linux/stat.h>
#include <linux/namei.h>
#include "allowlist.h" #include "allowlist.h"
#include "klog.h" // IWYU pragma: keep #include "klog.h" // IWYU pragma: keep
@@ -16,109 +14,15 @@
#include "throne_tracker.h" #include "throne_tracker.h"
#include "kernel_compat.h" #include "kernel_compat.h"
#include "dynamic_manager.h" #include "dynamic_manager.h"
#include "user_data_scanner.h"
#include <linux/kthread.h> #include <linux/kthread.h>
#include <linux/sched.h> #include <linux/sched.h>
#include <linux/delay.h>
uid_t ksu_manager_uid = KSU_INVALID_UID; uid_t ksu_manager_uid = KSU_INVALID_UID;
static struct task_struct *throne_thread; static struct task_struct *throne_thread;
#define USER_DATA_BASE_PATH "/data/user_de"
#define PRIMARY_USER_PATH "/data/user_de/0"
#define MAX_SUPPORTED_USERS 32 // Supports up to 32 users
#define DATA_PATH_LEN 384 // 384 is enough for /data/app/<package>/base.apk and /data/user_de/{userid}/<package>
#define SMALL_BUFFER_SIZE 64
#define SCHEDULE_INTERVAL 100
// Global work buffer to avoid stack allocation
struct work_buffers {
char path_buffer[DATA_PATH_LEN];
char package_buffer[KSU_MAX_PACKAGE_NAME];
char small_buffer[SMALL_BUFFER_SIZE];
uid_t user_ids_buffer[MAX_SUPPORTED_USERS];
};
struct uid_data {
struct list_head list;
u32 uid;
char package[KSU_MAX_PACKAGE_NAME];
uid_t user_id;
};
struct deferred_path_info {
struct list_head list;
char path[DATA_PATH_LEN];
char package_name[KSU_MAX_PACKAGE_NAME];
uid_t user_id;
};
struct user_scan_ctx {
struct list_head *deferred_paths;
uid_t user_id;
size_t pkg_count;
size_t error_count;
struct work_buffers *work_buf; // Passing the work buffer
size_t processed_count;
};
struct user_dir_ctx {
struct dir_context ctx;
struct user_scan_ctx *scan_ctx;
};
struct user_id_ctx {
struct dir_context ctx;
uid_t *user_ids;
size_t count;
size_t max_count;
size_t processed_count;
};
struct data_path {
char dirpath[DATA_PATH_LEN];
int depth;
struct list_head list;
};
struct apk_path_hash {
unsigned int hash;
bool exists;
struct list_head list;
};
static struct list_head apk_path_hash_list;
struct my_dir_context {
struct dir_context ctx;
struct list_head *data_path_list;
char *parent_dir;
void *private_data;
int depth;
int *stop;
bool found_dynamic_manager;
struct work_buffers *work_buf; // Passing the work buffer
size_t processed_count;
};
// https://docs.kernel.org/filesystems/porting.html
// filldir_t (readdir callbacks) calling conventions have changed. Instead of returning 0 or -E... it returns bool now. false means "no more" (as -E... used to) and true - "keep going" (as 0 in old calling conventions). Rationale: callers never looked at specific -E... values anyway. -> iterate_shared() instances require no changes at all, all filldir_t ones in the tree converted.
#if LINUX_VERSION_CODE >= KERNEL_VERSION(6, 1, 0)
#define FILLDIR_RETURN_TYPE bool
#define FILLDIR_ACTOR_CONTINUE true
#define FILLDIR_ACTOR_STOP false
#else
#define FILLDIR_RETURN_TYPE int
#define FILLDIR_ACTOR_CONTINUE 0
#define FILLDIR_ACTOR_STOP -EINVAL
#endif
static struct work_buffers *get_work_buffer(void)
{
static struct work_buffers global_buffer;
return &global_buffer;
}
static int get_pkg_from_apk_path(char *pkg, const char *path) static int get_pkg_from_apk_path(char *pkg, const char *path)
{ {
int len = strlen(path); int len = strlen(path);
@@ -196,346 +100,31 @@ static void crown_manager(const char *apk, struct list_head *uid_data,
} }
} }
FILLDIR_RETURN_TYPE scan_user_packages(struct dir_context *ctx, const char *name, struct data_path {
int namelen, loff_t off, u64 ino, unsigned int d_type) char dirpath[DATA_PATH_LEN];
{ int depth;
struct user_dir_ctx *uctx = container_of(ctx, struct user_dir_ctx, ctx); struct list_head list;
struct user_scan_ctx *scan_ctx = uctx->scan_ctx; };
if (!scan_ctx || !scan_ctx->deferred_paths) struct apk_path_hash {
return FILLDIR_ACTOR_STOP; unsigned int hash;
bool exists;
struct list_head list;
};
scan_ctx->processed_count++; static struct list_head apk_path_hash_list;
if (scan_ctx->processed_count % SCHEDULE_INTERVAL == 0) {
cond_resched();
}
if (d_type != DT_DIR || namelen <= 0) struct my_dir_context {
return FILLDIR_ACTOR_CONTINUE; struct dir_context ctx;
if (name[0] == '.' && (namelen == 1 || (namelen == 2 && name[1] == '.'))) struct list_head *data_path_list;
return FILLDIR_ACTOR_CONTINUE; char *parent_dir;
void *private_data;
if (namelen >= KSU_MAX_PACKAGE_NAME) { int depth;
pr_warn("Package name too long: %.*s (user %u)\n", namelen, name, scan_ctx->user_id); int *stop;
scan_ctx->error_count++; bool found_dynamic_manager;
return FILLDIR_ACTOR_CONTINUE; struct work_buffers *work_buf; // Passing the work buffer
} size_t processed_count;
};
struct deferred_path_info *path_info = kzalloc(sizeof(struct deferred_path_info), GFP_KERNEL);
if (!path_info) {
pr_err("Memory allocation failed for path info: %.*s\n", namelen, name);
scan_ctx->error_count++;
return FILLDIR_ACTOR_CONTINUE;
}
int path_len = snprintf(path_info->path, sizeof(path_info->path),
"%s/%u/%.*s", USER_DATA_BASE_PATH, scan_ctx->user_id, namelen, name);
if (path_len >= sizeof(path_info->path)) {
pr_err("Path too long for: %.*s (user %u)\n", namelen, name, scan_ctx->user_id);
kfree(path_info);
scan_ctx->error_count++;
return FILLDIR_ACTOR_CONTINUE;
}
path_info->user_id = scan_ctx->user_id;
size_t copy_len = min_t(size_t, namelen, KSU_MAX_PACKAGE_NAME - 1);
strncpy(path_info->package_name, name, copy_len);
path_info->package_name[copy_len] = '\0';
list_add_tail(&path_info->list, scan_ctx->deferred_paths);
scan_ctx->pkg_count++;
return FILLDIR_ACTOR_CONTINUE;
}
static int process_deferred_paths(struct list_head *deferred_paths, struct list_head *uid_list)
{
struct deferred_path_info *path_info, *n;
int success_count = 0;
list_for_each_entry_safe(path_info, n, deferred_paths, list) {
struct path path;
int err = kern_path(path_info->path, LOOKUP_FOLLOW, &path);
if (err) {
pr_debug("Path lookup failed: %s (%d)\n", path_info->path, err);
list_del(&path_info->list);
kfree(path_info);
continue;
}
struct kstat stat;
#if LINUX_VERSION_CODE >= KERNEL_VERSION(4,11,0) || defined(KSU_HAS_NEW_VFS_GETATTR)
err = vfs_getattr(&path, &stat, STATX_UID, AT_STATX_SYNC_AS_STAT);
#else
err = vfs_getattr(&path, &stat);
#endif
path_put(&path);
if (err) {
pr_debug("Failed to get attributes: %s (%d)\n", path_info->path, err);
list_del(&path_info->list);
kfree(path_info);
continue;
}
uid_t uid = from_kuid(&init_user_ns, stat.uid);
if (uid == (uid_t)-1) {
pr_warn("Invalid UID for: %s\n", path_info->path);
list_del(&path_info->list);
kfree(path_info);
continue;
}
struct uid_data *uid_entry = kzalloc(sizeof(struct uid_data), GFP_KERNEL);
if (!uid_entry) {
pr_err("Memory allocation failed for UID entry: %s\n", path_info->path);
list_del(&path_info->list);
kfree(path_info);
continue;
}
uid_entry->uid = uid;
uid_entry->user_id = path_info->user_id;
strncpy(uid_entry->package, path_info->package_name, KSU_MAX_PACKAGE_NAME - 1);
uid_entry->package[KSU_MAX_PACKAGE_NAME - 1] = '\0';
list_add_tail(&uid_entry->list, uid_list);
success_count++;
pr_info("Package: %s, UID: %u, User: %u\n", uid_entry->package, uid, path_info->user_id);
list_del(&path_info->list);
kfree(path_info);
if (success_count % 10 == 0) {
cond_resched();
}
}
return success_count;
}
// Scan the primary user
static int scan_primary_user_apps(struct list_head *uid_list,
size_t *pkg_count, size_t *error_count,
struct work_buffers *work_buf)
{
struct file *dir_file;
struct list_head deferred_paths;
int ret;
*pkg_count = *error_count = 0;
INIT_LIST_HEAD(&deferred_paths);
pr_info("Scanning primary user (0) applications in %s\n", PRIMARY_USER_PATH);
dir_file = ksu_filp_open_compat(PRIMARY_USER_PATH, O_RDONLY, 0);
if (IS_ERR(dir_file)) {
pr_err("Cannot open primary user path: %s (%ld)\n", PRIMARY_USER_PATH, PTR_ERR(dir_file));
return PTR_ERR(dir_file);
}
struct user_scan_ctx scan_ctx = {
.deferred_paths = &deferred_paths,
.user_id = 0,
.pkg_count = 0,
.error_count = 0,
.work_buf = work_buf,
.processed_count = 0
};
struct user_dir_ctx uctx = {
.ctx.actor = scan_user_packages,
.scan_ctx = &scan_ctx
};
ret = iterate_dir(dir_file, &uctx.ctx);
filp_close(dir_file, NULL);
int processed = process_deferred_paths(&deferred_paths, uid_list);
*pkg_count = processed;
*error_count = scan_ctx.error_count;
pr_info("Primary user scan completed: %zu packages found, %zu errors\n",
*pkg_count, *error_count);
return ret;
}
FILLDIR_RETURN_TYPE collect_user_ids(struct dir_context *ctx, const char *name,
int namelen, loff_t off, u64 ino, unsigned int d_type)
{
struct user_id_ctx *uctx = container_of(ctx, struct user_id_ctx, ctx);
uctx->processed_count++;
if (uctx->processed_count % SCHEDULE_INTERVAL == 0) {
cond_resched();
}
if (d_type != DT_DIR || namelen <= 0)
return FILLDIR_ACTOR_CONTINUE;
if (name[0] == '.' && (namelen == 1 || (namelen == 2 && name[1] == '.')))
return FILLDIR_ACTOR_CONTINUE;
uid_t uid = 0;
for (int i = 0; i < namelen; i++) {
if (name[i] < '0' || name[i] > '9')
return FILLDIR_ACTOR_CONTINUE; // Skip non-numeric entries
uid = uid * 10 + (name[i] - '0');
}
if (uctx->count >= uctx->max_count)
return FILLDIR_ACTOR_STOP;
uctx->user_ids[uctx->count++] = uid;
return FILLDIR_ACTOR_CONTINUE;
}
// Retrieve all active users (optional)
static int get_all_active_users(struct work_buffers *work_buf, size_t *found_count)
{
struct file *dir_file;
int ret;
*found_count = 0;
dir_file = ksu_filp_open_compat(USER_DATA_BASE_PATH, O_RDONLY, 0);
if (IS_ERR(dir_file)) {
pr_err("Cannot open user data base path: %s (%ld)\n", USER_DATA_BASE_PATH, PTR_ERR(dir_file));
return PTR_ERR(dir_file);
}
struct user_id_ctx uctx = {
.ctx.actor = collect_user_ids,
.user_ids = work_buf->user_ids_buffer,
.count = 0,
.max_count = MAX_SUPPORTED_USERS,
.processed_count = 0
};
ret = iterate_dir(dir_file, &uctx.ctx);
filp_close(dir_file, NULL);
*found_count = uctx.count;
if (uctx.count > 0) {
pr_info("Found %zu active users: ", uctx.count);
for (size_t i = 0; i < uctx.count; i++) {
pr_cont("%u ", work_buf->user_ids_buffer[i]);
}
pr_cont("\n");
}
return ret;
}
// Scan other users' applications (optional)
static int scan_secondary_users_apps(struct list_head *uid_list,
struct work_buffers *work_buf, size_t user_count,
size_t *total_pkg_count, size_t *total_error_count)
{
int ret = 0;
*total_pkg_count = *total_error_count = 0;
for (size_t i = 0; i < user_count; i++) {
// Skip the main user since it was already scanned in the first step.
if (work_buf->user_ids_buffer[i] == 0)
continue;
struct file *dir_file;
struct list_head deferred_paths;
INIT_LIST_HEAD(&deferred_paths);
snprintf(work_buf->path_buffer, sizeof(work_buf->path_buffer),
"%s/%u", USER_DATA_BASE_PATH, work_buf->user_ids_buffer[i]);
dir_file = ksu_filp_open_compat(work_buf->path_buffer, O_RDONLY, 0);
if (IS_ERR(dir_file)) {
pr_debug("Cannot open user path: %s (%ld)\n", work_buf->path_buffer, PTR_ERR(dir_file));
(*total_error_count)++;
continue;
}
struct user_scan_ctx scan_ctx = {
.deferred_paths = &deferred_paths,
.user_id = work_buf->user_ids_buffer[i],
.pkg_count = 0,
.error_count = 0,
.work_buf = work_buf,
.processed_count = 0
};
struct user_dir_ctx uctx = {
.ctx.actor = scan_user_packages,
.scan_ctx = &scan_ctx
};
ret = iterate_dir(dir_file, &uctx.ctx);
filp_close(dir_file, NULL);
int processed = process_deferred_paths(&deferred_paths, uid_list);
*total_pkg_count += processed;
*total_error_count += scan_ctx.error_count;
if (processed > 0 || scan_ctx.error_count > 0)
pr_info("User %u: %d packages, %zu errors\n",
work_buf->user_ids_buffer[i], processed, scan_ctx.error_count);
cond_resched();
}
return ret;
}
int scan_user_data_for_uids(struct list_head *uid_list, bool scan_all_users)
{
if (!uid_list)
return -EINVAL;
struct work_buffers *work_buf = get_work_buffer();
if (!work_buf) {
pr_err("Failed to get work buffer\n");
return -ENOMEM;
}
// Scan the primary user (User 0)
size_t primary_pkg_count, primary_error_count;
int ret = scan_primary_user_apps(uid_list, &primary_pkg_count, &primary_error_count, work_buf);
if (ret < 0 && primary_pkg_count == 0) {
pr_err("Primary user scan failed completely: %d\n", ret);
return ret;
}
// If you don't need to scan all users, stop here.
if (!scan_all_users) {
pr_info("Scan completed (primary user only): %zu packages, %zu errors\n",
primary_pkg_count, primary_error_count);
return primary_pkg_count > 0 ? 0 : -ENOENT;
}
// Retrieve all active users
size_t active_users;
ret = get_all_active_users(work_buf, &active_users);
if (ret < 0 || active_users == 0) {
pr_warn("Failed to get active users, using primary user only: %d\n", ret);
return primary_pkg_count > 0 ? 0 : -ENOENT;
}
size_t secondary_pkg_count, secondary_error_count;
ret = scan_secondary_users_apps(uid_list, work_buf, active_users,
&secondary_pkg_count, &secondary_error_count);
size_t total_packages = primary_pkg_count + secondary_pkg_count;
size_t total_errors = primary_error_count + secondary_error_count;
if (total_errors > 0)
pr_warn("Scan completed with %zu errors\n", total_errors);
pr_info("Complete scan finished: %zu users, %zu total packages\n",
active_users, total_packages);
return total_packages > 0 ? 0 : -ENOENT;
}
FILLDIR_RETURN_TYPE my_actor(struct dir_context *ctx, const char *name, FILLDIR_RETURN_TYPE my_actor(struct dir_context *ctx, const char *name,
int namelen, loff_t off, u64 ino, int namelen, loff_t off, u64 ino,
@@ -572,13 +161,13 @@ FILLDIR_RETURN_TYPE my_actor(struct dir_context *ctx, const char *name,
if (snprintf(work_buf->path_buffer, DATA_PATH_LEN, "%s/%.*s", my_ctx->parent_dir, if (snprintf(work_buf->path_buffer, DATA_PATH_LEN, "%s/%.*s", my_ctx->parent_dir,
namelen, name) >= DATA_PATH_LEN) { namelen, name) >= DATA_PATH_LEN) {
pr_err("Path too long: %s/%.*s\n", my_ctx->parent_dir, namelen, pr_err("Path too long: %s/%.*s\n", my_ctx->parent_dir, namelen,
name); name);
return FILLDIR_ACTOR_CONTINUE; return FILLDIR_ACTOR_CONTINUE;
} }
if (d_type == DT_DIR && my_ctx->depth > 0 && if (d_type == DT_DIR && my_ctx->depth > 0 &&
(my_ctx->stop && !*my_ctx->stop)) { (my_ctx->stop && !*my_ctx->stop)) {
struct data_path *data = kmalloc(sizeof(struct data_path), GFP_KERNEL); struct data_path *data = kmalloc(sizeof(struct data_path), GFP_ATOMIC);
if (!data) { if (!data) {
pr_err("Failed to allocate memory for %s\n", work_buf->path_buffer); pr_err("Failed to allocate memory for %s\n", work_buf->path_buffer);
@@ -616,7 +205,7 @@ FILLDIR_RETURN_TYPE my_actor(struct dir_context *ctx, const char *name,
crown_manager(work_buf->path_buffer, my_ctx->private_data, crown_manager(work_buf->path_buffer, my_ctx->private_data,
signature_index, work_buf); signature_index, work_buf);
struct apk_path_hash *apk_data = kmalloc(sizeof(struct apk_path_hash), GFP_KERNEL); struct apk_path_hash *apk_data = kmalloc(sizeof(struct apk_path_hash), GFP_ATOMIC);
if (apk_data) { if (apk_data) {
apk_data->hash = hash; apk_data->hash = hash;
apk_data->exists = true; apk_data->exists = true;
@@ -627,22 +216,22 @@ FILLDIR_RETURN_TYPE my_actor(struct dir_context *ctx, const char *name,
my_ctx->private_data, 0, work_buf); my_ctx->private_data, 0, work_buf);
if (!my_ctx->found_dynamic_manager && !ksu_is_dynamic_manager_enabled()) { if (!my_ctx->found_dynamic_manager && !ksu_is_dynamic_manager_enabled()) {
*my_ctx->stop = 1; *my_ctx->stop = 1;
} }
// Manager found, clear APK cache list // Manager found, clear APK cache list
if (!ksu_is_dynamic_manager_enabled()) { if (!ksu_is_dynamic_manager_enabled()) {
list_for_each_entry_safe(pos, n, &apk_path_hash_list, list) { list_for_each_entry_safe(pos, n, &apk_path_hash_list, list) {
list_del(&pos->list); list_del(&pos->list);
kfree(pos); kfree(pos);
} }
} }
} else { } else {
struct apk_path_hash *apk_data = kmalloc(sizeof(struct apk_path_hash), GFP_KERNEL); struct apk_path_hash *apk_data = kmalloc(sizeof(struct apk_path_hash), GFP_ATOMIC);
if (apk_data) { if (apk_data) {
apk_data->hash = hash; apk_data->hash = hash;
apk_data->exists = true; apk_data->exists = true;
list_add_tail(&apk_data->list, &apk_path_hash_list); list_add_tail(&apk_data->list, &apk_path_hash_list);
} }
} }
} }
@@ -666,7 +255,7 @@ void search_manager(const char *path, int depth, struct list_head *uid_data)
INIT_LIST_HEAD(&apk_path_hash_list); INIT_LIST_HEAD(&apk_path_hash_list);
unsigned long data_app_magic = 0; unsigned long data_app_magic = 0;
bool found_dynamic_manager = false; bool found_dynamic_manager = false;
// Initialize APK cache list // Initialize APK cache list
struct apk_path_hash *pos, *n; struct apk_path_hash *pos, *n;
list_for_each_entry(pos, &apk_path_hash_list, list) { list_for_each_entry(pos, &apk_path_hash_list, list) {
@@ -700,7 +289,7 @@ void search_manager(const char *path, int depth, struct list_head *uid_data)
pr_err("Failed to open directory: %s, err: %ld\n", pos->dirpath, PTR_ERR(file)); pr_err("Failed to open directory: %s, err: %ld\n", pos->dirpath, PTR_ERR(file));
goto skip_iterate; goto skip_iterate;
} }
// grab magic on first folder, which is /data/app // grab magic on first folder, which is /data/app
if (!data_app_magic) { if (!data_app_magic) {
if (file->f_inode->i_sb->s_magic) { if (file->f_inode->i_sb->s_magic) {
@@ -711,7 +300,7 @@ void search_manager(const char *path, int depth, struct list_head *uid_data)
goto skip_iterate; goto skip_iterate;
} }
} }
if (file->f_inode->i_sb->s_magic != data_app_magic) { if (file->f_inode->i_sb->s_magic != data_app_magic) {
pr_info("%s: skip: %s magic: 0x%lx expected: 0x%lx\n", __func__, pos->dirpath, pr_info("%s: skip: %s magic: 0x%lx expected: 0x%lx\n", __func__, pos->dirpath,
file->f_inode->i_sb->s_magic, data_app_magic); file->f_inode->i_sb->s_magic, data_app_magic);
@@ -737,11 +326,12 @@ skip_iterate:
cond_resched(); cond_resched();
} }
// clear apk_path_hash_list unconditionally // Remove stale cached APK entries
pr_info("search manager: cleanup!\n");
list_for_each_entry_safe(pos, n, &apk_path_hash_list, list) { list_for_each_entry_safe(pos, n, &apk_path_hash_list, list) {
list_del(&pos->list); if (!pos->exists) {
kfree(pos); list_del(&pos->list);
kfree(pos);
}
} }
} }
@@ -753,7 +343,7 @@ static bool is_uid_exist(uid_t uid, char *package, void *data)
bool exist = false; bool exist = false;
list_for_each_entry(np, list, list) { list_for_each_entry(np, list, list) {
if (np->uid == uid % 100000 && if (np->uid == uid % 100000 &&
strncmp(np->package, package, KSU_MAX_PACKAGE_NAME) == 0) { strncmp(np->package, package, KSU_MAX_PACKAGE_NAME) == 0) {
exist = true; exist = true;
break; break;
} }
@@ -770,8 +360,8 @@ static void track_throne_function(void)
if (ret < 0) { if (ret < 0) {
pr_err("Improved UserDE UID scan failed: %d. scan_all_users=%d\n", ret, scan_all_users); pr_err("Improved UserDE UID scan failed: %d. scan_all_users=%d\n", ret, scan_all_users);
goto out; goto out;
} }
// now update uid list // now update uid list
struct uid_data *np; struct uid_data *np;

361
kernel/user_data_scanner.c Normal file
View File

@@ -0,0 +1,361 @@
#include <linux/err.h>
#include <linux/fs.h>
#include <linux/list.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/types.h>
#include <linux/version.h>
#include <linux/stat.h>
#include <linux/namei.h>
#include <linux/sched.h>
#include "klog.h"
#include "ksu.h"
#include "kernel_compat.h"
#include "user_data_scanner.h"
struct work_buffers *get_work_buffer(void)
{
static struct work_buffers global_buffer;
return &global_buffer;
}
FILLDIR_RETURN_TYPE scan_user_packages(struct dir_context *ctx, const char *name,
int namelen, loff_t off, u64 ino, unsigned int d_type)
{
struct user_dir_ctx *uctx = container_of(ctx, struct user_dir_ctx, ctx);
struct user_scan_ctx *scan_ctx = uctx->scan_ctx;
if (!scan_ctx || !scan_ctx->deferred_paths)
return FILLDIR_ACTOR_STOP;
scan_ctx->processed_count++;
if (scan_ctx->processed_count % SCHEDULE_INTERVAL == 0) {
cond_resched();
}
if (d_type != DT_DIR || namelen <= 0)
return FILLDIR_ACTOR_CONTINUE;
if (name[0] == '.' && (namelen == 1 || (namelen == 2 && name[1] == '.')))
return FILLDIR_ACTOR_CONTINUE;
if (namelen >= KSU_MAX_PACKAGE_NAME) {
pr_warn("Package name too long: %.*s (user %u)\n", namelen, name, scan_ctx->user_id);
scan_ctx->error_count++;
return FILLDIR_ACTOR_CONTINUE;
}
struct deferred_path_info *path_info = kzalloc(sizeof(struct deferred_path_info), GFP_KERNEL);
if (!path_info) {
pr_err("Memory allocation failed for path info: %.*s\n", namelen, name);
scan_ctx->error_count++;
return FILLDIR_ACTOR_CONTINUE;
}
int path_len = snprintf(path_info->path, sizeof(path_info->path),
"%s/%u/%.*s", USER_DATA_BASE_PATH, scan_ctx->user_id, namelen, name);
if (path_len >= sizeof(path_info->path)) {
pr_err("Path too long for: %.*s (user %u)\n", namelen, name, scan_ctx->user_id);
kfree(path_info);
scan_ctx->error_count++;
return FILLDIR_ACTOR_CONTINUE;
}
path_info->user_id = scan_ctx->user_id;
size_t copy_len = min_t(size_t, namelen, KSU_MAX_PACKAGE_NAME - 1);
strncpy(path_info->package_name, name, copy_len);
path_info->package_name[copy_len] = '\0';
list_add_tail(&path_info->list, scan_ctx->deferred_paths);
scan_ctx->pkg_count++;
return FILLDIR_ACTOR_CONTINUE;
}
static int process_deferred_paths(struct list_head *deferred_paths, struct list_head *uid_list)
{
struct deferred_path_info *path_info, *n;
int success_count = 0;
list_for_each_entry_safe(path_info, n, deferred_paths, list) {
struct path path;
int err = kern_path(path_info->path, LOOKUP_FOLLOW, &path);
if (err) {
pr_debug("Path lookup failed: %s (%d)\n", path_info->path, err);
list_del(&path_info->list);
kfree(path_info);
continue;
}
struct kstat stat;
#if LINUX_VERSION_CODE >= KERNEL_VERSION(4,11,0) || defined(KSU_HAS_NEW_VFS_GETATTR)
err = vfs_getattr(&path, &stat, STATX_UID, AT_STATX_SYNC_AS_STAT);
#else
err = vfs_getattr(&path, &stat);
#endif
path_put(&path);
if (err) {
pr_debug("Failed to get attributes: %s (%d)\n", path_info->path, err);
list_del(&path_info->list);
kfree(path_info);
continue;
}
uid_t uid = from_kuid(&init_user_ns, stat.uid);
if (uid == (uid_t)-1) {
pr_warn("Invalid UID for: %s\n", path_info->path);
list_del(&path_info->list);
kfree(path_info);
continue;
}
struct uid_data *uid_entry = kzalloc(sizeof(struct uid_data), GFP_KERNEL);
if (!uid_entry) {
pr_err("Memory allocation failed for UID entry: %s\n", path_info->path);
list_del(&path_info->list);
kfree(path_info);
continue;
}
uid_entry->uid = uid;
uid_entry->user_id = path_info->user_id;
strncpy(uid_entry->package, path_info->package_name, KSU_MAX_PACKAGE_NAME - 1);
uid_entry->package[KSU_MAX_PACKAGE_NAME - 1] = '\0';
list_add_tail(&uid_entry->list, uid_list);
success_count++;
pr_info("Package: %s, UID: %u, User: %u\n", uid_entry->package, uid, path_info->user_id);
list_del(&path_info->list);
kfree(path_info);
if (success_count % 10 == 0) {
cond_resched();
}
}
return success_count;
}
static int scan_primary_user_apps(struct list_head *uid_list,
size_t *pkg_count, size_t *error_count,
struct work_buffers *work_buf)
{
struct file *dir_file;
struct list_head deferred_paths;
int ret;
*pkg_count = *error_count = 0;
INIT_LIST_HEAD(&deferred_paths);
pr_info("Scanning primary user (0) applications in %s\n", PRIMARY_USER_PATH);
dir_file = ksu_filp_open_compat(PRIMARY_USER_PATH, O_RDONLY, 0);
if (IS_ERR(dir_file)) {
pr_err("Cannot open primary user path: %s (%ld)\n", PRIMARY_USER_PATH, PTR_ERR(dir_file));
return PTR_ERR(dir_file);
}
struct user_scan_ctx scan_ctx = {
.deferred_paths = &deferred_paths,
.user_id = 0,
.pkg_count = 0,
.error_count = 0,
.work_buf = work_buf,
.processed_count = 0
};
struct user_dir_ctx uctx = {
.ctx.actor = scan_user_packages,
.scan_ctx = &scan_ctx
};
ret = iterate_dir(dir_file, &uctx.ctx);
filp_close(dir_file, NULL);
int processed = process_deferred_paths(&deferred_paths, uid_list);
*pkg_count = processed;
*error_count = scan_ctx.error_count;
pr_info("Primary user scan completed: %zu packages found, %zu errors\n",
*pkg_count, *error_count);
return ret;
}
FILLDIR_RETURN_TYPE collect_user_ids(struct dir_context *ctx, const char *name,
int namelen, loff_t off, u64 ino, unsigned int d_type)
{
struct user_id_ctx *uctx = container_of(ctx, struct user_id_ctx, ctx);
uctx->processed_count++;
if (uctx->processed_count % SCHEDULE_INTERVAL == 0) {
cond_resched();
}
if (d_type != DT_DIR || namelen <= 0)
return FILLDIR_ACTOR_CONTINUE;
if (name[0] == '.' && (namelen == 1 || (namelen == 2 && name[1] == '.')))
return FILLDIR_ACTOR_CONTINUE;
uid_t uid = 0;
for (int i = 0; i < namelen; i++) {
if (name[i] < '0' || name[i] > '9')
return FILLDIR_ACTOR_CONTINUE;
uid = uid * 10 + (name[i] - '0');
}
if (uctx->count >= uctx->max_count)
return FILLDIR_ACTOR_STOP;
uctx->user_ids[uctx->count++] = uid;
return FILLDIR_ACTOR_CONTINUE;
}
static int get_all_active_users(struct work_buffers *work_buf, size_t *found_count)
{
struct file *dir_file;
int ret;
*found_count = 0;
dir_file = ksu_filp_open_compat(USER_DATA_BASE_PATH, O_RDONLY, 0);
if (IS_ERR(dir_file)) {
pr_err("Cannot open user data base path: %s (%ld)\n", USER_DATA_BASE_PATH, PTR_ERR(dir_file));
return PTR_ERR(dir_file);
}
struct user_id_ctx uctx = {
.ctx.actor = collect_user_ids,
.user_ids = work_buf->user_ids_buffer,
.count = 0,
.max_count = MAX_SUPPORTED_USERS,
.processed_count = 0
};
ret = iterate_dir(dir_file, &uctx.ctx);
filp_close(dir_file, NULL);
*found_count = uctx.count;
if (uctx.count > 0) {
pr_info("Found %zu active users: ", uctx.count);
for (size_t i = 0; i < uctx.count; i++) {
pr_cont("%u ", work_buf->user_ids_buffer[i]);
}
pr_cont("\n");
}
return ret;
}
static int scan_secondary_users_apps(struct list_head *uid_list,
struct work_buffers *work_buf, size_t user_count,
size_t *total_pkg_count, size_t *total_error_count)
{
int ret = 0;
*total_pkg_count = *total_error_count = 0;
for (size_t i = 0; i < user_count; i++) {
// Skip the main user since it was already scanned in the first step
if (work_buf->user_ids_buffer[i] == 0)
continue;
struct file *dir_file;
struct list_head deferred_paths;
INIT_LIST_HEAD(&deferred_paths);
snprintf(work_buf->path_buffer, sizeof(work_buf->path_buffer),
"%s/%u", USER_DATA_BASE_PATH, work_buf->user_ids_buffer[i]);
dir_file = ksu_filp_open_compat(work_buf->path_buffer, O_RDONLY, 0);
if (IS_ERR(dir_file)) {
pr_debug("Cannot open user path: %s (%ld)\n", work_buf->path_buffer, PTR_ERR(dir_file));
(*total_error_count)++;
continue;
}
struct user_scan_ctx scan_ctx = {
.deferred_paths = &deferred_paths,
.user_id = work_buf->user_ids_buffer[i],
.pkg_count = 0,
.error_count = 0,
.work_buf = work_buf,
.processed_count = 0
};
struct user_dir_ctx uctx = {
.ctx.actor = scan_user_packages,
.scan_ctx = &scan_ctx
};
ret = iterate_dir(dir_file, &uctx.ctx);
filp_close(dir_file, NULL);
int processed = process_deferred_paths(&deferred_paths, uid_list);
*total_pkg_count += processed;
*total_error_count += scan_ctx.error_count;
if (processed > 0 || scan_ctx.error_count > 0)
pr_info("User %u: %d packages, %zu errors\n",
work_buf->user_ids_buffer[i], processed, scan_ctx.error_count);
cond_resched();
}
return ret;
}
int scan_user_data_for_uids(struct list_head *uid_list, bool scan_all_users)
{
if (!uid_list)
return -EINVAL;
struct work_buffers *work_buf = get_work_buffer();
if (!work_buf) {
pr_err("Failed to get work buffer\n");
return -ENOMEM;
}
// Scan primary user (User 0)
size_t primary_pkg_count, primary_error_count;
int ret = scan_primary_user_apps(uid_list, &primary_pkg_count, &primary_error_count, work_buf);
if (ret < 0 && primary_pkg_count == 0) {
pr_err("Primary user scan failed completely: %d\n", ret);
return ret;
}
// If scanning all users is not required, stop here.
if (!scan_all_users) {
pr_info("Scan completed (primary user only): %zu packages, %zu errors\n",
primary_pkg_count, primary_error_count);
return primary_pkg_count > 0 ? 0 : -ENOENT;
}
// Retrieve all active users
size_t active_users;
ret = get_all_active_users(work_buf, &active_users);
if (ret < 0 || active_users == 0) {
pr_warn("Failed to get active users, using primary user only: %d\n", ret);
return primary_pkg_count > 0 ? 0 : -ENOENT;
}
size_t secondary_pkg_count, secondary_error_count;
ret = scan_secondary_users_apps(uid_list, work_buf, active_users,
&secondary_pkg_count, &secondary_error_count);
size_t total_packages = primary_pkg_count + secondary_pkg_count;
size_t total_errors = primary_error_count + secondary_error_count;
if (total_errors > 0)
pr_warn("Scan completed with %zu errors\n", total_errors);
pr_info("Complete scan finished: %zu users, %zu total packages\n",
active_users, total_packages);
return total_packages > 0 ? 0 : -ENOENT;
}

View File

@@ -0,0 +1,86 @@
#ifndef _KSU_USER_DATA_SCANNER_H_
#define _KSU_USER_DATA_SCANNER_H_
#include <linux/list.h>
#include <linux/types.h>
#include <linux/fs.h>
#define USER_DATA_BASE_PATH "/data/user_de"
#define PRIMARY_USER_PATH "/data/user_de/0"
#define DATA_PATH_LEN 384 // 384 is enough for /data/user_de/{userid}/<package> and /data/app/<package>/base.apk
#define MAX_SUPPORTED_USERS 32 // Supports up to 32 users
#define SMALL_BUFFER_SIZE 64
#define SCHEDULE_INTERVAL 100
// https://docs.kernel.org/filesystems/porting.html
// filldir_t (readdir callbacks) calling conventions have changed. Instead of returning 0 or -E... it returns bool now. false means "no more" (as -E... used to) and true - "keep going" (as 0 in old calling conventions). Rationale: callers never looked at specific -E... values anyway. -> iterate_shared() instances require no changes at all, all filldir_t ones in the tree converted.
#if LINUX_VERSION_CODE >= KERNEL_VERSION(6, 1, 0)
#define FILLDIR_RETURN_TYPE bool
#define FILLDIR_ACTOR_CONTINUE true
#define FILLDIR_ACTOR_STOP false
#else
#define FILLDIR_RETURN_TYPE int
#define FILLDIR_ACTOR_CONTINUE 0
#define FILLDIR_ACTOR_STOP -EINVAL
#endif
// Global work buffer to avoid stack allocation
struct work_buffers {
char path_buffer[DATA_PATH_LEN];
char package_buffer[KSU_MAX_PACKAGE_NAME];
char small_buffer[SMALL_BUFFER_SIZE];
uid_t user_ids_buffer[MAX_SUPPORTED_USERS];
};
struct work_buffers *get_work_buffer(void);
struct uid_data {
struct list_head list;
u32 uid;
char package[KSU_MAX_PACKAGE_NAME];
uid_t user_id;
};
struct deferred_path_info {
struct list_head list;
char path[DATA_PATH_LEN];
char package_name[KSU_MAX_PACKAGE_NAME];
uid_t user_id;
};
struct user_scan_ctx {
struct list_head *deferred_paths;
uid_t user_id;
size_t pkg_count;
size_t error_count;
struct work_buffers *work_buf;
size_t processed_count;
};
struct user_dir_ctx {
struct dir_context ctx;
struct user_scan_ctx *scan_ctx;
};
struct user_id_ctx {
struct dir_context ctx;
uid_t *user_ids;
size_t count;
size_t max_count;
size_t processed_count;
};
int scan_user_data_for_uids(struct list_head *uid_list, bool scan_all_users);
FILLDIR_RETURN_TYPE scan_user_packages(struct dir_context *ctx, const char *name,
int namelen, loff_t off, u64 ino, unsigned int d_type);
FILLDIR_RETURN_TYPE collect_user_ids(struct dir_context *ctx, const char *name,
int namelen, loff_t off, u64 ino, unsigned int d_type);
static int process_deferred_paths(struct list_head *deferred_paths, struct list_head *uid_list);
static int scan_primary_user_apps(struct list_head *uid_list, size_t *pkg_count,
size_t *error_count, struct work_buffers *work_buf);
static int get_all_active_users(struct work_buffers *work_buf, size_t *found_count);
static int scan_secondary_users_apps(struct list_head *uid_list, struct work_buffers *work_buf,
size_t user_count, size_t *total_pkg_count,
size_t *total_error_count);
#endif /* _KSU_USER_DATA_SCANNER_H_ */