Deprecated ADD_TRY_UMOUNT in favor of official kernel_umount; Synced with the latest commit of official KernelSU main repo

- Since official KSU has exposed kernel_umount API and provided meta module for handling mount operations, susfs can finally handover try_umount and auto add_try_umount to KSU and its meta module

- Synced with upstream, see e1e58ed737

Co-authored-by: simonpunk <simonpunk2016@gmail.com>

kernel/Kconfig

@@ -93,14 +93,6 @@ config KSU_SUSFS_SUS_KSTAT
 		- Allow spoofing the kstat of user-defined file/directory.
 		- Effective only on zygote spawned user app process.
 
-config KSU_SUSFS_TRY_UMOUNT
-	bool "Enable to use ksu's try_umount"
-	depends on KSU_SUSFS
-	default y
-	help
-		- Allow using try_umount to umount other user-defined mount paths prior to ksu's default umount paths.
-		- Effective only on zygote spawned umounted user app process.
-
 config KSU_SUSFS_SPOOF_UNAME
 	bool "Enable to spoof uname"
 	depends on KSU_SUSFS

kernel/allowlist.h

@@ -39,6 +39,7 @@ bool ksu_set_app_profile(struct app_profile *, bool persist);
 bool ksu_uid_should_umount(uid_t uid);
 struct root_profile *ksu_get_root_profile(uid_t uid);
 
+#ifndef CONFIG_KSU_SUSFS
 static inline bool is_appuid(uid_t uid)
 {
 	uid_t appid = uid % PER_USER_RANGE;
@@ -50,6 +51,7 @@ static inline bool is_isolated_process(uid_t uid)
     uid_t appid = uid % PER_USER_RANGE;
     return appid >= FIRST_ISOLATED_UID && appid <= LAST_ISOLATED_UID;
 }
+#endif // #ifndef CONFIG_KSU_SUSFS
 
 #ifdef CONFIG_KSU_MANUAL_SU
 bool ksu_temp_grant_root_once(uid_t uid);

kernel/kernel_umount.c

@@ -27,11 +27,7 @@
 
 #include "sulog.h"
 
-#ifndef CONFIG_KSU_SUSFS
 static bool ksu_kernel_umount_enabled = true;
-#else
-bool ksu_kernel_umount_enabled = true;
-#endif
 
 static int kernel_umount_feature_get(u64 *value)
 {
@@ -93,11 +89,7 @@ static void ksu_sys_umount(const char *mnt, int flags)
 
 #endif
 
-#ifndef CONFIG_KSU_SUSFS_TRY_UMOUNT
 static void try_umount(const char *mnt, int flags)
-#else
-void try_umount(const char *mnt, int flags)
-#endif // #ifndef CONFIG_KSU_SUSFS_TRY_UMOUNT
 {
 	struct path path;
 	int err = kern_path(mnt, 0, &path);
@@ -115,7 +107,6 @@ void try_umount(const char *mnt, int flags)
 }
 
 
-#if !defined(CONFIG_KSU_SUSFS) || !defined(CONFIG_KSU_SUSFS_TRY_UMOUNT)
 struct umount_tw {
 	struct callback_head cb;
 	const struct cred *old_cred;
@@ -150,7 +141,6 @@ int ksu_handle_umount(uid_t old_uid, uid_t new_uid)
 {
 	struct umount_tw *tw;
 
-#if defined(CONFIG_KSU_SUSFS) || !defined(CONFIG_KSU_SUSFS_TRY_UMOUNT)
 	// if there isn't any module mounted, just ignore it!
 	if (!ksu_module_mounted) {
 		return 0;
@@ -160,6 +150,7 @@ int ksu_handle_umount(uid_t old_uid, uid_t new_uid)
 		return 0;
 	}
 
+#ifndef CONFIG_KSU_SUSFS
 	// There are 5 scenarios:
     // 1. Normal app: zygote -> appuid
     // 2. Isolated process forked from zygote: zygote -> isolated_process
@@ -183,12 +174,14 @@ int ksu_handle_umount(uid_t old_uid, uid_t new_uid)
 		pr_info("handle umount ignore non zygote child: %d\n", current->pid);
 		return 0;
 	}
+#endif // #ifndef CONFIG_KSU_SUSFS
+
+	// umount the target mnt
+	pr_info("handle umount for uid: %d, pid: %d\n", new_uid, current->pid);
+
 #if __SULOG_GATE
 	ksu_sulog_report_syscall(new_uid, NULL, "setuid", NULL);
 #endif
-#endif // #if defined(CONFIG_KSU_SUSFS) || !defined(CONFIG_KSU_SUSFS_TRY_UMOUNT)
-	// umount the target mnt
-	pr_info("handle umount for uid: %d, pid: %d\n", new_uid, current->pid);
 
 	tw = kzalloc(sizeof(*tw), GFP_ATOMIC);
 	if (!tw)
@@ -208,7 +201,6 @@ int ksu_handle_umount(uid_t old_uid, uid_t new_uid)
 
 	return 0;
 }
-#endif // #if !defined(CONFIG_KSU_SUSFS) || !defined(CONFIG_KSU_SUSFS_TRY_UMOUNT)
 
 void ksu_kernel_umount_init(void)
 {

kernel/kernel_umount.h

@@ -8,10 +8,8 @@
 void ksu_kernel_umount_init(void);
 void ksu_kernel_umount_exit(void);
 
-#if !defined(CONFIG_KSU_SUSFS) || !defined(CONFIG_KSU_SUSFS_TRY_UMOUNT)
 // Handler function to be called from setresuid hook
 int ksu_handle_umount(uid_t old_uid, uid_t new_uid);
-#endif // #if !defined(CONFIG_KSU_SUSFS) || !defined(CONFIG_KSU_SUSFS_TRY_UMOUNT)
 
 // for the umount list
 struct mount_entry {

kernel/selinux/rules.c

@@ -141,7 +141,7 @@ void apply_kernelsu_rules(void)
 	
 #ifdef CONFIG_KSU_SUSFS
 	// Allow umount in zygote process without installing zygisk
-	ksu_allow(db, "zygote", "labeledfs", "filesystem", "unmount");
+	// ksu_allow(db, "zygote", "labeledfs", "filesystem", "unmount");
 	susfs_set_priv_app_sid();
 	susfs_set_init_sid();
 	susfs_set_ksu_sid();

kernel/setuid_hook.c

@@ -68,9 +68,6 @@ extern void susfs_run_sus_path_loop(uid_t uid);
 extern bool susfs_is_umount_for_zygote_iso_service_enabled;
 extern void susfs_reorder_mnt_id(void);
 #endif // #ifdef CONFIG_KSU_SUSFS_SUS_MOUNT
-#ifdef CONFIG_KSU_SUSFS_TRY_UMOUNT
-extern void susfs_try_umount(uid_t uid);
-#endif
 #endif // #ifdef CONFIG_KSU_SUSFS
 
 static bool ksu_enhanced_security_enabled = false;
@@ -297,19 +294,9 @@ int ksu_handle_setresuid(uid_t ruid, uid_t euid, uid_t suid){
 	return 0;
 
 do_umount:
-#ifndef CONFIG_KSU_SUSFS_TRY_UMOUNT
-	if (!ksu_kernel_umount_enabled || !ksu_module_mounted) {
-		goto skip_ksu_handle_umount;
-		
-	}
 	// Handle kernel umount
 	ksu_handle_umount(old_uid, new_uid);
 
-skip_ksu_handle_umount:
-#else
-    susfs_try_umount(new_uid);
-#endif // #ifndef CONFIG_KSU_SUSFS_TRY_UMOUNT
-
 	get_task_struct(current);
 
 #ifdef CONFIG_KSU_SUSFS_SUS_MOUNT

kernel/supercalls.c

@@ -470,7 +470,8 @@ static int do_manage_mark(void __user *arg)
 		cmd.result = (u32)ret;
 		break;
 #else
-		return -EINVAL;
+		cmd.result = 0;
+        break;
 #endif
 	}
 	case KSU_MARK_MARK: {
@@ -486,7 +487,9 @@ static int do_manage_mark(void __user *arg)
 			}
 		}
 #else
-		pr_info("susfs: cmd: KSU_MARK_MARK => do nothing\n");
+		if (cmd.pid != 0) {
+            return 0;
+        }
 #endif
 		break;
 	}
@@ -503,7 +506,9 @@ static int do_manage_mark(void __user *arg)
 			}
 		}
 #else
-		pr_info("susfs: cmd: KSU_MARK_UNMARK => do nothing\n");
+		if (cmd.pid != 0) {
+            return 0;
+        }
 #endif
 		break;
 	}
@@ -1024,12 +1029,6 @@ int ksu_handle_sys_reboot(int magic1, int magic2, unsigned int cmd, void __user
 			return 0;
 		}
 #endif //#ifdef CONFIG_KSU_SUSFS_SUS_KSTAT
-#ifdef CONFIG_KSU_SUSFS_TRY_UMOUNT
-		if (cmd == CMD_SUSFS_ADD_TRY_UMOUNT) {
-			susfs_add_try_umount(arg);
-			return 0;
-		}
-#endif //#ifdef CONFIG_KSU_SUSFS_TRY_UMOUNT
 #ifdef CONFIG_KSU_SUSFS_SPOOF_UNAME
 		if (cmd == CMD_SUSFS_SET_UNAME) {
 			susfs_set_uname(arg);