* These commits are carefully picked from upstream (tiann/KernelSU)
- Picked range:
8c5f485f27..e5f43a3427
Signed-off-by: Faris <rissu.ntk@gmail.com>
Co-authored-by: Wang Han <416810799@qq.com>
Co-authored-by: TwinbornPlate75 <3342733415@qq.com>
Co-authored-by: KOWX712 <leecc0503@gmail.com>
Co-authored-by: Ylarod <me@ylarod.cn>
Co-authored-by: YuKongA <70465933+YuKongA@users.noreply.github.com>
Co-authored-by: backslashxx <118538522+backslashxx@users.noreply.github.com>
Co-authored-by: 5ec1cff <56485584+5ec1cff@users.noreply.github.com>
Co-authored-by: weishu <twsxtd@gmail.com>
836 lines
21 KiB
C
836 lines
21 KiB
C
#include <linux/compiler.h>
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#include <linux/version.h>
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#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 11, 0)
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#include <linux/sched/task_stack.h>
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#else
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#include <linux/sched.h>
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#endif
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#include <linux/slab.h>
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#include <linux/task_work.h>
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#include <linux/thread_info.h>
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#include <linux/seccomp.h>
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#include <linux/capability.h>
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#include <linux/cred.h>
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#include <linux/dcache.h>
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#include <linux/fs.h>
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#include <linux/init.h>
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#include <linux/init_task.h>
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#include <linux/kernel.h>
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#include <linux/kprobes.h>
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#include <linux/mm.h>
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#include <linux/mount.h>
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#include <linux/namei.h>
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#include <linux/nsproxy.h>
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#include <linux/path.h>
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#include <linux/printk.h>
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#include <linux/sched.h>
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#include <linux/stddef.h>
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#include <linux/string.h>
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#include <linux/types.h>
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#include <linux/uaccess.h>
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#include <linux/uidgid.h>
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#ifndef KSU_HAS_PATH_UMOUNT
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#include <linux/syscalls.h> // sys_umount (<4.17) & ksys_umount (4.17+)
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#endif
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#include <linux/binfmts.h>
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#include <linux/err.h>
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#include "allowlist.h"
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#include "arch.h"
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#include "core_hook.h"
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#include "feature.h"
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#include "klog.h" // IWYU pragma: keep
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#include "ksu.h"
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#include "ksud.h"
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#include "manager.h"
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#include "selinux/selinux.h"
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#include "throne_tracker.h"
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#include "throne_comm.h"
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#include "kernel_compat.h"
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#include "supercalls.h"
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#include "sucompat.h"
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bool ksu_module_mounted __read_mostly = false;
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#ifndef DEVPTS_SUPER_MAGIC
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#define DEVPTS_SUPER_MAGIC 0x1cd1
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#endif
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extern int __ksu_handle_devpts(struct inode *inode); // sucompat.c
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#ifdef CONFIG_COMPAT
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bool ksu_is_compat __read_mostly = false;
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#endif
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static bool ksu_kernel_umount_enabled = true;
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static bool ksu_enhanced_security_enabled = false;
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static int kernel_umount_feature_get(u64 *value)
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{
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*value = ksu_kernel_umount_enabled ? 1 : 0;
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return 0;
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}
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static int kernel_umount_feature_set(u64 value)
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{
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bool enable = value != 0;
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ksu_kernel_umount_enabled = enable;
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pr_info("kernel_umount: set to %d\n", enable);
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return 0;
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}
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static const struct ksu_feature_handler kernel_umount_handler = {
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.feature_id = KSU_FEATURE_KERNEL_UMOUNT,
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.name = "kernel_umount",
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.get_handler = kernel_umount_feature_get,
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.set_handler = kernel_umount_feature_set,
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};
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static int enhanced_security_feature_get(u64 *value)
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{
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*value = ksu_enhanced_security_enabled ? 1 : 0;
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return 0;
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}
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static int enhanced_security_feature_set(u64 value)
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{
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bool enable = value != 0;
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ksu_enhanced_security_enabled = enable;
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pr_info("enhanced_security: set to %d\n", enable);
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return 0;
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}
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static const struct ksu_feature_handler enhanced_security_handler = {
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.feature_id = KSU_FEATURE_ENHANCED_SECURITY,
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.name = "enhanced_security",
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.get_handler = enhanced_security_feature_get,
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.set_handler = enhanced_security_feature_set,
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};
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static inline bool is_allow_su(void)
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{
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if (is_manager()) {
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// we are manager, allow!
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return true;
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}
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return ksu_is_allow_uid_for_current(current_uid().val);
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}
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static inline bool is_unsupported_uid(uid_t uid)
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{
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#define LAST_APPLICATION_UID 19999
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uid_t appid = uid % 100000;
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return appid > LAST_APPLICATION_UID;
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}
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#if LINUX_VERSION_CODE >= KERNEL_VERSION(6, 7, 0)
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static struct group_info root_groups = {
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.usage = REFCOUNT_INIT(2),
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};
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#else
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static struct group_info root_groups = { .usage = ATOMIC_INIT(2) };
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#endif
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static void setup_groups(struct root_profile *profile, struct cred *cred)
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{
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if (profile->groups_count > KSU_MAX_GROUPS) {
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pr_warn("Failed to setgroups, too large group: %d!\n",
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profile->uid);
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return;
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}
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if (profile->groups_count == 1 && profile->groups[0] == 0) {
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// setgroup to root and return early.
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if (cred->group_info)
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put_group_info(cred->group_info);
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cred->group_info = get_group_info(&root_groups);
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return;
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}
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u32 ngroups = profile->groups_count;
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struct group_info *group_info = groups_alloc(ngroups);
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if (!group_info) {
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pr_warn("Failed to setgroups, ENOMEM for: %d\n", profile->uid);
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return;
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}
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int i;
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for (i = 0; i < ngroups; i++) {
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gid_t gid = profile->groups[i];
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kgid_t kgid = make_kgid(current_user_ns(), gid);
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if (!gid_valid(kgid)) {
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pr_warn("Failed to setgroups, invalid gid: %d\n", gid);
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put_group_info(group_info);
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return;
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}
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#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 9, 0)
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group_info->gid[i] = kgid;
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#else
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GROUP_AT(group_info, i) = kgid;
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#endif
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}
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groups_sort(group_info);
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set_groups(cred, group_info);
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put_group_info(group_info);
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}
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static void disable_seccomp(struct task_struct *tsk)
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{
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assert_spin_locked(&tsk->sighand->siglock);
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// disable seccomp
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#if defined(CONFIG_GENERIC_ENTRY) && \
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LINUX_VERSION_CODE >= KERNEL_VERSION(5, 11, 0)
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clear_syscall_work(SECCOMP);
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#else
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clear_thread_flag(TIF_SECCOMP);
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#endif
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#ifdef CONFIG_SECCOMP
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tsk->seccomp.mode = 0;
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if (tsk->seccomp.filter) {
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// 5.9+ have filter_count and use seccomp_filter_release
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#if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 9, 0)
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seccomp_filter_release(tsk);
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atomic_set(&tsk->seccomp.filter_count, 0);
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#else
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// for 6.11+ kernel support?
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#if LINUX_VERSION_CODE < KERNEL_VERSION(5, 9, 0)
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put_seccomp_filter(tsk);
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#endif
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tsk->seccomp.filter = NULL;
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#endif
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}
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#endif
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}
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void escape_to_root(void)
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{
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struct cred *cred;
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#ifdef KSU_SHOULD_USE_NEW_TP
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struct task_struct *p = current;
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struct task_struct *t;
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#endif
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cred = prepare_creds();
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if (!cred) {
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pr_warn("prepare_creds failed!\n");
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return;
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}
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if (cred->euid.val == 0) {
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pr_warn("Already root, don't escape!\n");
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abort_creds(cred);
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return;
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}
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struct root_profile *profile = ksu_get_root_profile(cred->uid.val);
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cred->uid.val = profile->uid;
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cred->suid.val = profile->uid;
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cred->euid.val = profile->uid;
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cred->fsuid.val = profile->uid;
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cred->gid.val = profile->gid;
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cred->fsgid.val = profile->gid;
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cred->sgid.val = profile->gid;
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cred->egid.val = profile->gid;
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cred->securebits = 0;
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BUILD_BUG_ON(sizeof(profile->capabilities.effective) !=
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sizeof(kernel_cap_t));
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// setup capabilities
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// we need CAP_DAC_READ_SEARCH becuase `/data/adb/ksud` is not accessible for non root process
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// we add it here but don't add it to cap_inhertiable, it would be dropped automaticly after exec!
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u64 cap_for_ksud =
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profile->capabilities.effective | CAP_DAC_READ_SEARCH;
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memcpy(&cred->cap_effective, &cap_for_ksud,
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sizeof(cred->cap_effective));
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memcpy(&cred->cap_permitted, &profile->capabilities.effective,
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sizeof(cred->cap_permitted));
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memcpy(&cred->cap_bset, &profile->capabilities.effective,
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sizeof(cred->cap_bset));
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setup_groups(profile, cred);
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commit_creds(cred);
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spin_lock_irq(¤t->sighand->siglock);
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disable_seccomp(current);
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spin_unlock_irq(¤t->sighand->siglock);
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setup_selinux(profile->selinux_domain);
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#ifdef KSU_SHOULD_USE_NEW_TP
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for_each_thread (p, t) {
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ksu_set_task_tracepoint_flag(t);
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}
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#endif
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}
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extern void ext4_unregister_sysfs(struct super_block *sb);
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void nuke_ext4_sysfs(void)
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{
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#ifdef CONFIG_EXT4_FS
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struct path path;
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int err = kern_path("/data/adb/modules", 0, &path);
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if (err) {
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pr_err("%s: failed to get path, err %d\n", __func__, err);
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return;
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}
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struct super_block *sb = path.dentry->d_inode->i_sb;
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const char *name = sb->s_type->name;
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if (strcmp(name, "ext4") != 0) {
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pr_info("nuke_module: skipping s_type: %s\n", name);
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path_put(&path);
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return;
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}
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ext4_unregister_sysfs(sb);
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pr_info("nuke_module: ext4 sysfs unregistered.n\n");
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path_put(&path);
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#endif
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}
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static bool is_appuid(kuid_t uid)
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{
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#define PER_USER_RANGE 100000
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#define FIRST_APPLICATION_UID 10000
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#define LAST_APPLICATION_UID 19999
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uid_t appid = uid.val % PER_USER_RANGE;
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return appid >= FIRST_APPLICATION_UID && appid <= LAST_APPLICATION_UID;
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}
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static bool should_umount(struct path *path)
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{
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if (!path) {
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return false;
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}
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if (current->nsproxy->mnt_ns == init_nsproxy.mnt_ns) {
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pr_info("ignore global mnt namespace process: %d\n",
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current_uid().val);
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return false;
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}
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if (path->mnt && path->mnt->mnt_sb && path->mnt->mnt_sb->s_type) {
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const char *fstype = path->mnt->mnt_sb->s_type->name;
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return strcmp(fstype, "overlay") == 0;
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}
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return false;
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}
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#if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 9, 0) || \
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defined(KSU_HAS_PATH_UMOUNT)
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extern int path_umount(struct path *path, int flags);
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#define ksu_umount_mnt(__unused, path, flags) (path_umount(path, flags))
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#else
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static int ksu_sys_umount(const char *mnt, int flags)
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{
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char __user *usermnt = (char __user *)mnt;
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mm_segment_t old_fs;
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int ret; // although asmlinkage long
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old_fs = get_fs();
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set_fs(KERNEL_DS);
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#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 17, 0)
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ret = ksys_umount(usermnt, flags);
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#else
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ret = sys_umount(usermnt, flags); // cuz asmlinkage long sys##name
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#endif
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set_fs(old_fs);
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return ret;
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}
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#define ksu_umount_mnt(mnt, __unused, flags) \
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({ \
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int ret; \
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path_put(__unused); \
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ret = ksu_sys_umount(mnt, flags); \
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ret; \
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})
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#endif
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static void try_umount(const char *mnt, bool check_mnt, int flags)
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{
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struct path path;
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int ret;
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int err = kern_path(mnt, 0, &path);
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if (err) {
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return;
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}
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if (path.dentry != path.mnt->mnt_root) {
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// it is not root mountpoint, maybe umounted by others already.
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path_put(&path);
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return;
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}
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// we are only interest in some specific mounts
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if (check_mnt && !should_umount(&path)) {
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path_put(&path);
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return;
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}
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ret = ksu_umount_mnt(mnt, &path, flags);
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if (ret) {
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#ifdef CONFIG_KSU_DEBUG
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pr_info("%s: path: %s, ret: %d\n", __func__, mnt, ret);
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#endif
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}
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}
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static void ksu_do_umount_lists(void)
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{
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// fixme: use `collect_mounts` and `iterate_mount` to iterate all mountpoint and
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// filter the mountpoint whose target is `/data/adb`
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try_umount("/odm", true, 0);
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try_umount("/system", true, 0);
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try_umount("/vendor", true, 0);
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try_umount("/product", true, 0);
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try_umount("/system_ext", true, 0);
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try_umount("/data/adb/modules", false, MNT_DETACH);
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try_umount("/debug_ramdisk", false, MNT_DETACH);
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try_umount("/sbin", false, MNT_DETACH);
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}
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#if defined(MODULE) || defined(KSU_KPROBES_HOOK)
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struct umount_tw {
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struct callback_head cb;
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const struct cred *old_cred;
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};
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static void umount_tw_func(struct callback_head *cb)
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{
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struct umount_tw *tw = container_of(cb, struct umount_tw, cb);
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const struct cred *saved = NULL;
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if (tw->old_cred) {
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saved = override_creds(tw->old_cred);
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}
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ksu_do_umount_lists();
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if (saved)
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revert_creds(saved);
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if (tw->old_cred)
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put_cred(tw->old_cred);
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kfree(tw);
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}
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#endif
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// force_sig kcompat, TODO: move it out of core_hook.c
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// https://elixir.bootlin.com/linux/v5.3-rc1/source/kernel/signal.c#L1613
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#if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 3, 0)
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#define __force_sig(sig) force_sig(sig)
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#else
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#define __force_sig(sig) force_sig(sig, current)
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#endif
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int ksu_handle_setuid(struct cred *new, const struct cred *old)
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{
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if (!new || !old) {
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return 0;
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}
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kuid_t new_uid = new->uid;
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kuid_t old_uid = old->uid;
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// pr_info("handle_setuid from %d to %d\n", old_uid.val, new_uid.val);
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if (0 != old_uid.val) {
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// old process is not root, ignore it.
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if (ksu_enhanced_security_enabled) {
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// disallow any non-ksu domain escalation from non-root to root!
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if (unlikely(new_uid.val) == 0) {
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if (!is_ksu_domain()) {
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pr_warn("find suspicious EoP: %d %s, from %d to %d\n",
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current->pid, current->comm,
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old_uid.val, new_uid.val);
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__force_sig(SIGKILL);
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return 0;
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}
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}
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// disallow appuid decrease to any other uid if it is allowed to su
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if (is_appuid(old_uid)) {
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if (new_uid.val < old_uid.val &&
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!ksu_is_allow_uid_for_current(
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old_uid.val)) {
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pr_warn("find suspicious EoP: %d %s, from %d to %d\n",
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current->pid, current->comm,
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old_uid.val, new_uid.val);
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__force_sig(SIGKILL);
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return 0;
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}
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}
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}
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return 0;
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}
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#ifdef KSU_SHOULD_USE_NEW_TP
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if (new_uid.val == 2000 && ksu_su_compat_enabled) {
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ksu_set_task_tracepoint_flag(current);
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}
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#endif
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if (!is_appuid(new_uid) || is_unsupported_uid(new_uid.val)) {
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// pr_info("handle setuid ignore non application or isolated uid: %d\n", new_uid.val);
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return 0;
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}
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// if on private space, see if its possibly the manager
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if (new_uid.val > 100000 &&
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new_uid.val % 100000 == ksu_get_manager_uid()) {
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ksu_set_manager_uid(new_uid.val);
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}
|
|
|
|
#if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 10, 0)
|
|
if (ksu_get_manager_uid() == new_uid.val) {
|
|
pr_info("install fd for ksu manager(uid=%d)\n", new_uid.val);
|
|
ksu_install_fd();
|
|
spin_lock_irq(¤t->sighand->siglock);
|
|
ksu_seccomp_allow_cache(current->seccomp.filter, __NR_reboot);
|
|
spin_unlock_irq(¤t->sighand->siglock);
|
|
ksu_set_task_tracepoint_flag(current);
|
|
return 0;
|
|
}
|
|
|
|
if (ksu_is_allow_uid_for_current(new_uid.val)) {
|
|
if (current->seccomp.mode == SECCOMP_MODE_FILTER &&
|
|
current->seccomp.filter) {
|
|
spin_lock_irq(¤t->sighand->siglock);
|
|
ksu_seccomp_allow_cache(current->seccomp.filter,
|
|
__NR_reboot);
|
|
spin_unlock_irq(¤t->sighand->siglock);
|
|
}
|
|
if (ksu_su_compat_enabled) {
|
|
ksu_set_task_tracepoint_flag(current);
|
|
}
|
|
} else {
|
|
if (ksu_su_compat_enabled) {
|
|
// Disable syscall tracepoint sucompat for non-allowed processes
|
|
ksu_clear_task_tracepoint_flag(current);
|
|
}
|
|
}
|
|
#else
|
|
if (ksu_is_allow_uid_for_current(new_uid.val)) {
|
|
spin_lock_irq(¤t->sighand->siglock);
|
|
disable_seccomp(current);
|
|
spin_unlock_irq(¤t->sighand->siglock);
|
|
|
|
if (ksu_get_manager_uid() == new_uid.val) {
|
|
pr_info("install fd for ksu manager(uid=%d)\n",
|
|
new_uid.val);
|
|
ksu_install_fd();
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
// this hook is used for umounting overlayfs for some uid, if there isn't any module mounted, just ignore it!
|
|
if (!ksu_module_mounted) {
|
|
return 0;
|
|
}
|
|
|
|
if (!ksu_kernel_umount_enabled) {
|
|
return 0;
|
|
}
|
|
|
|
if (!ksu_uid_should_umount(new_uid.val)) {
|
|
return 0;
|
|
} else {
|
|
#ifdef CONFIG_KSU_DEBUG
|
|
pr_info("uid: %d should not umount!\n", current_uid().val);
|
|
#endif
|
|
}
|
|
|
|
// check old process's selinux context, if it is not zygote, ignore it!
|
|
// because some su apps may setuid to untrusted_app but they are in global mount namespace
|
|
// when we umount for such process, that is a disaster!
|
|
if (!is_zygote(old)) {
|
|
pr_info("handle umount ignore non zygote child: %d\n",
|
|
current->pid);
|
|
return 0;
|
|
}
|
|
#ifdef CONFIG_KSU_DEBUG
|
|
// umount the target mnt
|
|
pr_info("handle umount for uid: %d, pid: %d\n", new_uid.val,
|
|
current->pid);
|
|
#endif
|
|
|
|
#if defined(MODULE) || defined(KSU_KPROBES_HOOK)
|
|
struct umount_tw *tw;
|
|
tw = kmalloc(sizeof(*tw), GFP_ATOMIC);
|
|
if (!tw)
|
|
return 0;
|
|
|
|
tw->old_cred = get_current_cred();
|
|
tw->cb.func = umount_tw_func;
|
|
|
|
#if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 7, 8)
|
|
int err = task_work_add(current, &tw->cb, TWA_RESUME);
|
|
#else
|
|
int err = task_work_add(current, &tw->cb, true);
|
|
#endif
|
|
|
|
if (err) {
|
|
if (tw->old_cred) {
|
|
put_cred(tw->old_cred);
|
|
}
|
|
kfree(tw);
|
|
pr_warn("unmount add task_work failed\n");
|
|
}
|
|
#else
|
|
ksu_do_umount_lists();
|
|
#endif
|
|
|
|
return 0;
|
|
}
|
|
|
|
int ksu_inode_permission(struct inode *inode, int mask)
|
|
{
|
|
if (inode && inode->i_sb
|
|
&& unlikely(inode->i_sb->s_magic == DEVPTS_SUPER_MAGIC)) {
|
|
//pr_info("%s: handling devpts for: %s \n", __func__, current->comm);
|
|
__ksu_handle_devpts(inode);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
int ksu_bprm_check(struct linux_binprm *bprm)
|
|
{
|
|
char *filename = (char *)bprm->filename;
|
|
|
|
if (likely(!ksu_execveat_hook))
|
|
return 0;
|
|
|
|
#ifdef CONFIG_COMPAT
|
|
static bool compat_check_done __read_mostly = false;
|
|
if ( unlikely(!compat_check_done) && unlikely(!strcmp(filename, "/data/adb/ksud"))
|
|
&& !memcmp(bprm->buf, "\x7f\x45\x4c\x46", 4) ) {
|
|
if (bprm->buf[4] == 0x01 )
|
|
ksu_is_compat = true;
|
|
|
|
pr_info("%s: %s ELF magic found! ksu_is_compat: %d \n", __func__, filename, ksu_is_compat);
|
|
compat_check_done = true;
|
|
}
|
|
#endif
|
|
|
|
ksu_handle_pre_ksud(filename);
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
int ksu_handle_sys_reboot(int magic1, int magic2, unsigned int cmd,
|
|
void __user **arg)
|
|
{
|
|
if (magic1 != KSU_INSTALL_MAGIC1)
|
|
return 0;
|
|
|
|
#ifdef CONFIG_KSU_DEBUG
|
|
pr_info("sys_reboot: intercepted call! magic: 0x%x id: %d\n", magic1,
|
|
magic2);
|
|
#endif
|
|
|
|
// Check if this is a request to install KSU fd
|
|
if (magic2 == KSU_INSTALL_MAGIC2) {
|
|
int fd = ksu_install_fd();
|
|
// downstream: dereference all arg usage!
|
|
if (copy_to_user((void __user *)*arg, &fd, sizeof(fd))) {
|
|
pr_err("install ksu fd reply err\n");
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
// extensions
|
|
|
|
return 0;
|
|
}
|
|
|
|
// -- For old kernel compat?
|
|
#if !defined(MODULE) && !defined(KSU_KPROBE_HOOK)
|
|
static int ksu_task_fix_setuid(struct cred *new, const struct cred *old,
|
|
int flags)
|
|
{
|
|
return ksu_handle_setuid(new, old);
|
|
}
|
|
|
|
// kernel 4.4 and 4.9
|
|
#if LINUX_VERSION_CODE < KERNEL_VERSION(4, 10, 0) || \
|
|
defined(CONFIG_IS_HW_HISI) || defined(CONFIG_KSU_ALLOWLIST_WORKAROUND)
|
|
static int ksu_key_permission(key_ref_t key_ref, const struct cred *cred,
|
|
unsigned perm)
|
|
{
|
|
if (init_session_keyring != NULL) {
|
|
return 0;
|
|
}
|
|
if (strcmp(current->comm, "init")) {
|
|
// we are only interested in `init` process
|
|
return 0;
|
|
}
|
|
init_session_keyring = cred->session_keyring;
|
|
pr_info("kernel_compat: got init_session_keyring\n");
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
#include <linux/lsm_hooks.h>
|
|
static struct security_hook_list ksu_hooks[] = {
|
|
LSM_HOOK_INIT(task_fix_setuid, ksu_task_fix_setuid),
|
|
LSM_HOOK_INIT(inode_permission, ksu_inode_permission),
|
|
#ifndef KSU_KPROBES_HOOK
|
|
LSM_HOOK_INIT(bprm_check_security, ksu_bprm_check),
|
|
#endif
|
|
#if LINUX_VERSION_CODE < KERNEL_VERSION(4, 10, 0) || \
|
|
defined(CONFIG_IS_HW_HISI) || defined(CONFIG_KSU_ALLOWLIST_WORKAROUND)
|
|
LSM_HOOK_INIT(key_permission, ksu_key_permission)
|
|
#endif
|
|
};
|
|
|
|
#if LINUX_VERSION_CODE >= KERNEL_VERSION(6, 8, 0)
|
|
static const struct lsm_id ksu_lsmid = {
|
|
.name = "ksu",
|
|
.id = 912,
|
|
};
|
|
#endif
|
|
|
|
static void ksu_lsm_hook_init(void)
|
|
{
|
|
#if LINUX_VERSION_CODE >= KERNEL_VERSION(6, 8, 0)
|
|
security_add_hooks(ksu_hooks, ARRAY_SIZE(ksu_hooks), &ksu_lsmid);
|
|
#elif LINUX_VERSION_CODE >= KERNEL_VERSION(4, 11, 0)
|
|
security_add_hooks(ksu_hooks, ARRAY_SIZE(ksu_hooks), "ksu");
|
|
#else
|
|
// https://elixir.bootlin.com/linux/v4.10.17/source/include/linux/lsm_hooks.h#L1892
|
|
security_add_hooks(ksu_hooks, ARRAY_SIZE(ksu_hooks));
|
|
#endif
|
|
pr_info("LSM hooks initialized.\n");
|
|
}
|
|
#else
|
|
static void ksu_lsm_hook_init(void)
|
|
{
|
|
}
|
|
#endif
|
|
|
|
// -- For KPROBE and LKM handler
|
|
#if defined(MODULE) || defined(KSU_KPROBES_HOOK)
|
|
static int reboot_handler_pre(struct kprobe *p, struct pt_regs *regs)
|
|
{
|
|
struct pt_regs *real_regs = PT_REAL_REGS(regs);
|
|
int magic1 = (int)PT_REGS_PARM1(real_regs);
|
|
int magic2 = (int)PT_REGS_PARM2(real_regs);
|
|
int cmd = (int)PT_REGS_PARM3(real_regs);
|
|
void __user **arg = (void __user **)&PT_REGS_SYSCALL_PARM4(real_regs);
|
|
|
|
return ksu_handle_sys_reboot(magic1, magic2, cmd, arg);
|
|
}
|
|
|
|
static struct kprobe reboot_kp = {
|
|
.symbol_name = REBOOT_SYMBOL,
|
|
.pre_handler = reboot_handler_pre,
|
|
};
|
|
|
|
// 2. cap_task_fix_setuid hook for handling setuid
|
|
static int cap_task_fix_setuid_handler_pre(struct kprobe *p,
|
|
struct pt_regs *regs)
|
|
{
|
|
struct cred *new = (struct cred *)PT_REGS_PARM1(regs);
|
|
const struct cred *old = (const struct cred *)PT_REGS_PARM2(regs);
|
|
|
|
ksu_handle_setuid(new, old);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct kprobe cap_task_fix_setuid_kp = {
|
|
.symbol_name = "cap_task_fix_setuid",
|
|
.pre_handler = cap_task_fix_setuid_handler_pre,
|
|
};
|
|
|
|
static int ksu_kprobe_init(void)
|
|
{
|
|
int rc = 0;
|
|
|
|
// Register reboot kprobe
|
|
rc = register_kprobe(&reboot_kp);
|
|
if (rc) {
|
|
pr_err("reboot kprobe failed: %d\n", rc);
|
|
return rc;
|
|
}
|
|
pr_info("reboot kprobe registered successfully\n");
|
|
|
|
// Register cap_task_fix_setuid kprobe
|
|
rc = register_kprobe(&cap_task_fix_setuid_kp);
|
|
if (rc) {
|
|
pr_err("cap_task_fix_setuid kprobe failed: %d\n", rc);
|
|
unregister_kprobe(&reboot_kp);
|
|
return rc;
|
|
}
|
|
pr_info("cap_task_fix_setuid kprobe registered successfully\n");
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void ksu_kprobe_exit(void)
|
|
{
|
|
unregister_kprobe(&cap_task_fix_setuid_kp);
|
|
unregister_kprobe(&reboot_kp);
|
|
}
|
|
|
|
void __init ksu_core_init(void)
|
|
{
|
|
int rc = ksu_kprobe_init();
|
|
if (rc) {
|
|
pr_err("ksu_kprobe_init failed: %d\n", rc);
|
|
}
|
|
|
|
if (ksu_register_feature_handler(&kernel_umount_handler)) {
|
|
pr_err("Failed to register umount feature handler\n");
|
|
}
|
|
|
|
if (ksu_register_feature_handler(&enhanced_security_handler)) {
|
|
pr_err("Failed to register enhanced security feature handler\n");
|
|
}
|
|
}
|
|
|
|
void ksu_core_exit(void)
|
|
{
|
|
pr_info("ksu_core_exit\n");
|
|
ksu_kprobe_exit();
|
|
ksu_unregister_feature_handler(KSU_FEATURE_KERNEL_UMOUNT);
|
|
}
|
|
#else
|
|
|
|
void __init ksu_core_init(void)
|
|
{
|
|
ksu_lsm_hook_init();
|
|
|
|
if (ksu_register_feature_handler(&kernel_umount_handler)) {
|
|
pr_err("Failed to register umount feature handler\n");
|
|
}
|
|
|
|
if (ksu_register_feature_handler(&enhanced_security_handler)) {
|
|
pr_err("Failed to register enhanced security feature handler\n");
|
|
}
|
|
}
|
|
|
|
void ksu_core_exit(void)
|
|
{
|
|
ksu_unregister_feature_handler(KSU_FEATURE_KERNEL_UMOUNT);
|
|
|
|
ksu_uid_exit();
|
|
ksu_throne_comm_exit();
|
|
|
|
ksu_unregister_feature_handler(KSU_FEATURE_ENHANCED_SECURITY);
|
|
}
|
|
|
|
#endif
|