kernel: Implement SUSFS 1.5.3

kernel/Kconfig

@@ -16,4 +16,139 @@ config KSU_DEBUG
 	help
 	  Enable KernelSU debug mode.
 
+menu "KernelSU - SUSFS"
+config KSU_SUSFS
+    bool "KernelSU addon - SUSFS"
+    depends on KSU
+    default y
+    help
+      Patch and Enable SUSFS to kernel with KernelSU.
+
+config KSU_SUSFS_SUS_PATH
+    bool "Enable to hide suspicious path (NOT recommended)"
+    depends on KSU_SUSFS
+    default y
+    help
+      - Allow hiding the user-defined path and all its sub-paths from various system calls.
+      - tmpfs filesystem is not allowed to be added. 
+      - Effective on process with uid > 2000 only.
+      - Use with cautious as it may cause performance loss and will be vulnerable to side channel attacks,
+        just disable this feature if it doesn't work for you or you don't need it at all.
+
+config KSU_SUSFS_SUS_MOUNT
+    bool "Enable to hide suspicious mounts"
+    depends on KSU_SUSFS
+    default y
+    help
+      - Allow hiding the user-defined mount paths from /proc/self/[mounts|mountinfo|mountstat].
+      - Effective on all processes for hiding mount entries.
+      - Mounts mounted by process with ksu domain will be forced to be assigned the dev name "KSU".
+      - mnt_id and mnt_group_id of the sus mount will be assigned to a much bigger number to solve the issue of id not being contiguous.  
+
+config KSU_SUSFS_AUTO_ADD_SUS_KSU_DEFAULT_MOUNT
+    bool "Enable to hide KSU's default mounts automatically (experimental)"
+    depends on KSU_SUSFS_SUS_MOUNT
+    default y
+    help
+      - Automatically add KSU's default mounts to sus_mount.
+      - No susfs command is needed in userspace.
+      - Only mount operation from process with ksu domain will be checked.
+
+config KSU_SUSFS_AUTO_ADD_SUS_BIND_MOUNT
+    bool "Enable to hide suspicious bind mounts automatically (experimental)"
+    depends on KSU_SUSFS_SUS_MOUNT
+    default y
+    help
+      - Automatically add binded mounts to sus_mount.
+      - No susfs command is needed in userspace.
+      - Only mount operation from process with ksu domain will be checked.
+
+config KSU_SUSFS_SUS_KSTAT
+    bool "Enable to spoof suspicious kstat"
+    depends on KSU_SUSFS
+    default y
+    help
+      - Allow spoofing the kstat of user-defined file/directory.
+      - Effective on all processes.
+
+config KSU_SUSFS_SUS_OVERLAYFS
+    bool "Enable to automatically spoof kstat and kstatfs for overlayed files/directories"
+    depends on KSU_SUSFS
+    default y
+    help
+      - Automatically spoof the kstat and kstatfs for overlayed files/directories.
+      - No susfs command is needed in userspace.
+      - Effective on all processes.
+
+config KSU_SUSFS_TRY_UMOUNT
+    bool "Enable to use ksu's ksu_try_umount"
+    depends on KSU_SUSFS
+    default y
+    help
+      - Allow using ksu_try_umount to umount other user-defined mount paths prior to ksu's default umount paths.
+      - Effective on all NO-root-access-granted processes.
+
+config KSU_SUSFS_AUTO_ADD_TRY_UMOUNT_FOR_BIND_MOUNT
+    bool "Enable to add bind mounts to ksu's ksu_try_umount automatically (experimental)"
+    depends on KSU_SUSFS_TRY_UMOUNT
+    default y
+    help
+      - Automatically add binded mounts to ksu's ksu_try_umount.
+      - No susfs command is needed in userspace.
+      - Only mount operation from process with ksu domain will be checked.
+
+config KSU_SUSFS_SPOOF_UNAME
+    bool "Enable to spoof uname"
+    depends on KSU_SUSFS
+    default y
+    help
+      - Allow spoofing the string returned by uname syscall to user-defined string.
+      - Effective on all processes.
+
+config KSU_SUSFS_ENABLE_LOG
+    bool "Enable logging susfs log to kernel"
+    depends on KSU_SUSFS
+    default y
+    help
+      - Allow logging susfs log to kernel, uncheck it to completely disable all susfs log.
+
+config KSU_SUSFS_HIDE_KSU_SUSFS_SYMBOLS
+    bool "Enable to automatically hide ksu and susfs symbols from /proc/kallsyms"
+    depends on KSU_SUSFS
+    default y
+    help
+      - Automatically hide ksu and susfs symbols from '/proc/kallsyms'.
+      - Effective on all processes.
+
+config KSU_SUSFS_SPOOF_PROC_CMDLINE
+    bool "Enable to spoof /proc/cmdline"
+    depends on KSU_SUSFS
+    default y
+    help
+      - Spoof the output of /proc/cmdline with a user-defined file.
+      - Effective on all processes.
+
+config KSU_SUSFS_OPEN_REDIRECT
+    bool "Enable to redirect a path to be opened with another path (experimental)"
+    depends on KSU_SUSFS
+    default y
+    help
+      - Allow redirecting a target path to be opened with another user-defined path.
+      - Effective only on processes with uid < 2000.
+      - Please be reminded that process with open access to the target and redirected path can be detected.
+
+config KSU_SUSFS_SUS_SU
+    bool "Enable SUS-SU in runtime temporarily"
+    depends on KSU_SUSFS && KPROBES && HAVE_KPROBES && KPROBE_EVENTS
+    default y
+    help
+      - Allow user to enable or disable core ksu kprobes hooks temporarily in runtime. There are 2 working modes for sus_su.
+      - Mode 0 (default): Disable sus_su, and enable ksu kprobe hooks for su instead.
+      - Mode 1 (deprecated): 
+      - Mode 2: Enable sus_su, and disable ksu kprobe hooks for su, which means the kernel inline hooks are enabled,
+                the same as the su implementaion of non-gki kernel without kprobe supported.
+      - Only apps with root access granted by ksu manager are allowed to get root.
+
+endmenu
+
 endmenu

kernel/Makefile

@@ -56,14 +56,112 @@ $(info -- KernelSU Manager signature hash: $(KSU_EXPECTED_HASH))
 ccflags-y += -DEXPECTED_SIZE=$(KSU_EXPECTED_SIZE)
 ccflags-y += -DEXPECTED_HASH=\"$(KSU_EXPECTED_HASH)\"
 
-ifeq ($(shell grep -q "int path_umount" $(srctree)/fs/namespace.c; echo $$?),0)
+#ifeq ($(shell grep -q "int path_umount" $(srctree)/fs/namespace.c; echo $$?),0)
+#ccflags-y += -DKSU_UMOUNT
+#else
+#$(info -- Did you know you can backport path_umount to fs/namespace.c from 5.9?)
+#$(info -- Read: https://kernelsu.org/guide/how-to-integrate-for-non-gki.html#how-to-backport-path-umount)
+#endif
+
 ccflags-y += -DKSU_UMOUNT
-else
-$(info -- Did you know you can backport path_umount to fs/namespace.c from 5.9?)
-$(info -- Read: https://kernelsu.org/guide/how-to-integrate-for-non-gki.html#how-to-backport-path-umount)
+
+ifneq ($(shell grep -Eq "^static int can_umount" $(srctree)/fs/namespace.c; echo $$?),0)
+$(info -- KSU_SUSFS: adding function 'static int can_umount(const struct path *path, int flags);' to $(srctree)/fs/namespace.c)
+CAN_UMOUNT = static int can_umount(const struct path *path, int flags)\n\
+{\n\t\
+        struct mount *mnt = real_mount(path->mnt);\n\t\
+        if (flags & ~(MNT_FORCE | MNT_DETACH | MNT_EXPIRE | UMOUNT_NOFOLLOW))\n\t\t\
+                return -EINVAL;\n\t\
+        if (!may_mount())\n\t\t\
+                return -EPERM;\n\t\
+        if (path->dentry != path->mnt->mnt_root)\n\t\t\
+                return -EINVAL;\n\t\
+        if (!check_mnt(mnt))\n\t\t\
+                return -EINVAL;\n\t\
+        if (mnt->mnt.mnt_flags & MNT_LOCKED)\n\t\t\
+                return -EINVAL;\n\t\
+        if (flags & MNT_FORCE && !capable(CAP_SYS_ADMIN))\n\t\t\
+                return -EPERM;\n\t\
+        return 0;\n\
+}\n
+$(shell sed -i '/^static bool is_mnt_ns_file/i $(CAN_UMOUNT)' $(srctree)/fs/namespace.c;)
+endif
+
+ifneq ($(shell grep -Eq "^int path_umount" $(srctree)/fs/namespace.c; echo $$?),0)
+$(info -- KSU_SUSFS: adding function 'int path_umount(struct path *path, int flags);' to $(srctree)/fs/namespace.c)
+PATH_UMOUNT = int path_umount(struct path *path, int flags)\n\
+{\n\t\
+        struct mount *mnt = real_mount(path->mnt);\n\t\
+        int ret;\n\t\
+        ret = can_umount(path, flags);\n\t\
+        if (!ret)\n\t\t\
+                ret = do_umount(mnt, flags);\n\t\
+        dput(path->dentry);\n\t\
+        mntput_no_expire(mnt);\n\t\
+        return ret;\n\
+}\n
+$(shell sed -i '/^static bool is_mnt_ns_file/i $(PATH_UMOUNT)' $(srctree)/fs/namespace.c;)
+endif
+
+ifneq ($(shell grep -Eq "^int path_umount" $(srctree)/fs/internal.h; echo $$?),0)
+$(shell sed -i '/^extern void __init mnt_init/a int path_umount(struct path *path, int flags);' $(srctree)/fs/internal.h;)
+$(info -- KSU_SUSFS: adding 'int path_umount(struct path *path, int flags);' to $(srctree)/fs/internal.h)
 endif
 
 ccflags-y += -Wno-implicit-function-declaration -Wno-strict-prototypes -Wno-int-conversion -Wno-gcc-compat
 ccflags-y += -Wno-declaration-after-statement -Wno-unused-function
 
+ifeq ($(shell test -e $(srctree)/fs/susfs.c; echo $$?),0)
+$(eval SUSFS_VERSION=$(shell cat $(srctree)/include/linux/susfs.h | grep -E '^#define SUSFS_VERSION' | cut -d' ' -f3 | sed 's/"//g'))
+$(info -- SUSFS_VERSION: $(SUSFS_VERSION))
+ifdef KSU_SUSFS
+ccflags-y += -DKSU_SUSFS
+endif
+ifdef KSU_SUSFS_SUS_PATH
+ccflags-y += -DKSU_SUSFS_SUS_PATH
+endif
+ifdef KSU_SUSFS_SUS_MOUNT
+ccflags-y += -DKSU_SUSFS_SUS_MOUNT
+endif
+ifdef KSU_SUSFS_AUTO_ADD_SUS_KSU_DEFAULT_MOUNT
+ccflags-y += -DKSU_SUSFS_AUTO_ADD_SUS_KSU_DEFAULT_MOUNT
+endif
+ifdef KSU_SUSFS_AUTO_ADD_SUS_BIND_MOUNT
+ccflags-y += -DKSU_SUSFS_AUTO_ADD_SUS_BIND_MOUNT
+endif
+ifdef KSU_SUSFS_SUS_KSTAT
+ccflags-y += -DKSU_SUSFS_SUS_KSTAT
+endif
+ifdef KSU_SUSFS_SUS_OVERLAYFS
+ccflags-y += -DKSU_SUSFS_SUS_OVERLAYFS
+endif
+ifdef KSU_SUSFS_TRY_UMOUNT
+ccflags-y += -DKSU_SUSFS_TRY_UMOUNT
+endif
+ifdef KSU_SUSFS_AUTO_ADD_TRY_UMOUNT_FOR_BIND_MOUNT
+ccflags-y += -DKSU_SUSFS_AUTO_ADD_TRY_UMOUNT_FOR_BIND_MOUNT
+endif
+ifdef KSU_SUSFS_SPOOF_UNAME
+ccflags-y += -DKSU_SUSFS_SPOOF_UNAME
+endif
+ifdef KSU_SUSFS_ENABLE_LOG
+ccflags-y += -DKSU_SUSFS_ENABLE_LOG
+endif
+ifdef KSU_SUSFS_HIDE_KSU_SUSFS_SYMBOLS
+ccflags-y += -DKSU_SUSFS_HIDE_KSU_SUSFS_SYMBOLS
+endif
+ifdef KSU_SUSFS_SPOOF_PROC_CMDLINE
+ccflags-y += -DKSU_SUSFS_SPOOF_PROC_CMDLINE
+endif
+ifdef KSU_SUSFS_OPEN_REDIRECT
+ccflags-y += -DKSU_SUSFS_OPEN_REDIRECT
+endif
+ifdef KSU_SUSFS_SUS_SU
+ccflags-y += -DKSU_SUSFS_SUS_SU
+endif
+else
+$(info -- You have not integrate susfs in your kernel.)
+$(info -- Read: https://gitlab.com/simonpunk/susfs4ksu)
+endif
+
 # Keep a new line here!! Because someone may append config

kernel/allowlist.c

@@ -92,7 +92,7 @@ static uint8_t allow_list_bitmap[PAGE_SIZE] __read_mostly __aligned(PAGE_SIZE);
 static struct work_struct ksu_save_work;
 static struct work_struct ksu_load_work;
 
-bool persistent_allow_list(void);
+static bool persistent_allow_list(void);
 
 void ksu_show_allow_list(void)
 {
@@ -267,7 +267,7 @@ bool __ksu_is_allow_uid(uid_t uid)
 
 	if (unlikely(uid == 0)) {
 		// already root, but only allow our domain.
-		return is_ksu_domain();
+		return ksu_is_ksu_domain();
 	}
 
 	if (forbid_system_uid(uid)) {
@@ -352,7 +352,7 @@ bool ksu_get_allow_list(int *array, int *length, bool allow)
 	return true;
 }
 
-void do_save_allow_list(struct work_struct *work)
+static void do_save_allow_list(struct work_struct *work)
 {
 	u32 magic = FILE_MAGIC;
 	u32 version = FILE_FORMAT_VERSION;
@@ -394,7 +394,7 @@ void do_save_allow_list(struct work_struct *work)
 	filp_close(fp, 0);
 }
 
-void do_load_allow_list(struct work_struct *work)
+static void do_load_allow_list(struct work_struct *work)
 {
 	loff_t off = 0;
 	ssize_t ret = 0;
@@ -484,7 +484,7 @@ void ksu_prune_allowlist(bool (*is_uid_valid)(uid_t, char *, void *), void *data
 }
 
 // make sure allow list works cross boot
-bool persistent_allow_list(void)
+static bool persistent_allow_list(void)
 {
 	return ksu_queue_work(&ksu_save_work);
 }

kernel/apk_sign.c

@@ -314,7 +314,7 @@ module_param_cb(ksu_debug_manager_uid, &expected_size_ops,
 
 #endif
 
-bool is_manager_apk(char *path)
+bool ksu_is_manager_apk(char *path)
 {
 	return check_v2_signature(path, EXPECTED_SIZE, EXPECTED_HASH);
 }

kernel/apk_sign.h

@@ -3,6 +3,6 @@
 
 #include <linux/types.h>
 
-bool is_manager_apk(char *path);
+bool ksu_is_manager_apk(char *path);
 
 #endif