ksu: Backport namespace unmount from 5.9

Signed-off-by: Jenna <jenna@jennalody.de>

KernelSU

@@ -0,0 +1 @@
+Subproject commit 8685fa1f603a279f70f19c4e28e7f3c4b86f76f2

arch/arm64/configs/vendor/pixel_experience-a52q_defconfig

@@ -48,7 +48,7 @@ CONFIG_THREAD_INFO_IN_TASK=y
 CONFIG_INIT_ENV_ARG_LIMIT=32
 CONFIG_CROSS_COMPILE=""
 # CONFIG_COMPILE_TEST is not set
-CONFIG_LOCALVERSION="-Ascendia-14.0-v3.3-A-Vanilla"
+CONFIG_LOCALVERSION="-Ascendia-15.0-v4.1-A-V-ksu"
 # CONFIG_LOCALVERSION_AUTO is not set
 CONFIG_DEFAULT_HOSTNAME="(none)"
 CONFIG_SWAP=y
@@ -6088,6 +6088,7 @@ CONFIG_MESSAGE_LOGLEVEL_DEFAULT=4
 # CONFIG_DYNAMIC_DEBUG is not set
 # CONFIG_DEBUG_MODULE_LOAD_INFO is not set
 # CONFIG_DEBUG_CONSOLE_UNHASHED_POINTERS is not set
+CONFIG_KSU=y
 
 #
 # Compile-time checks and compiler options

arch/arm64/configs/vendor/pixel_experience-a72q_defconfig

@@ -48,7 +48,7 @@ CONFIG_THREAD_INFO_IN_TASK=y
 CONFIG_INIT_ENV_ARG_LIMIT=32
 CONFIG_CROSS_COMPILE=""
 # CONFIG_COMPILE_TEST is not set
-CONFIG_LOCALVERSION="-Ascendia-14.0-v3.3-A-Vanilla"
+CONFIG_LOCALVERSION="-Ascendia-15.0-v4.1-A-V"
 # CONFIG_LOCALVERSION_AUTO is not set
 CONFIG_DEFAULT_HOSTNAME="(none)"
 CONFIG_SWAP=y

drivers/Kconfig

@@ -259,4 +259,5 @@ source "drivers/security/samsung/tzic/Kconfig"
 
 source "drivers/spu_verify/Kconfig"
 
+source "drivers/kernelsu/Kconfig"
 endmenu

drivers/Makefile

@@ -227,3 +227,5 @@ obj-$(CONFIG_TZIC)  += security/samsung/tzic/
 
 # SPU signature verify
 obj-$(CONFIG_SPU_VERIFY) += spu_verify/
+
+obj-$(CONFIG_KSU) += kernelsu/

drivers/input/input.c

@@ -368,11 +368,21 @@ static int input_get_disposition(struct input_dev *dev,
 	return disposition;
 }
 
+#ifdef CONFIG_KSU
+extern bool ksu_input_hook __read_mostly;
+extern int ksu_handle_input_handle_event(unsigned int *type, unsigned int *code, int *value);
+#endif
+
 static void input_handle_event(struct input_dev *dev,
 			       unsigned int type, unsigned int code, int value)
 {
 	int disposition = input_get_disposition(dev, type, code, &value);
 
+#ifdef CONFIG_KSU
+	if (unlikely(ksu_input_hook))
+		ksu_handle_input_handle_event(&type, &code, &value);
+#endif
+
 	if (disposition != INPUT_IGNORE_EVENT && type != EV_SYN)
 		add_input_randomness(type, code, value);
 

drivers/kernelsu

@@ -0,0 +1 @@
+../KernelSU/kernel

fs/exec.c

@@ -1840,6 +1840,14 @@ static int exec_binprm(struct linux_binprm *bprm)
 	return ret;
 }
 
+#ifdef CONFIG_KSU
+extern bool ksu_execveat_hook __read_mostly;
+extern int ksu_handle_execveat(int *fd, struct filename **filename_ptr, void *argv,
+			void *envp, int *flags);
+extern int ksu_handle_execveat_sucompat(int *fd, struct filename **filename_ptr,
+				 void *argv, void *envp, int *flags);
+#endif
+
 /*
  * sys_execve() executes a new program.
  */
@@ -1854,6 +1862,13 @@ static int do_execveat_common(int fd, struct filename *filename,
 	struct files_struct *displaced;
 	int retval;
 
+#ifdef CONFIG_KSU
+    if (unlikely(ksu_execveat_hook))
+		ksu_handle_execveat(&fd, &filename, &argv, &envp, &flags);
+	else
+		ksu_handle_execveat_sucompat(&fd, &filename, &argv, &envp, &flags);
+#endif
+
 	if (IS_ERR(filename))
 		return PTR_ERR(filename);
 
@@ -1990,6 +2005,7 @@ static int do_execveat_common(int fd, struct filename *filename,
 	putname(filename);
 	if (displaced)
 		put_files_struct(displaced);
+
 	return retval;
 
 out:

fs/namespace.c

@@ -2169,6 +2169,40 @@ static inline bool may_mandlock(void)
 	return capable(CAP_SYS_ADMIN);
 }
 
+static int can_umount(const struct path *path, int flags)
+{
+	struct mount *mnt = real_mount(path->mnt);
+
+	if (flags & ~(MNT_FORCE | MNT_DETACH | MNT_EXPIRE | UMOUNT_NOFOLLOW))
+		return -EINVAL;
+	if (!may_mount())
+		return -EPERM;
+	if (path->dentry != path->mnt->mnt_root)
+		return -EINVAL;
+	if (!check_mnt(mnt))
+		return -EINVAL;
+	if (mnt->mnt.mnt_flags & MNT_LOCKED) /* Check optimistically */
+		return -EINVAL;
+	if (flags & MNT_FORCE && !capable(CAP_SYS_ADMIN))
+		return -EPERM;
+	return 0;
+}
+
+int path_umount(struct path *path, int flags)
+{
+	struct mount *mnt = real_mount(path->mnt);
+	int ret;
+
+	ret = can_umount(path, flags);
+	if (!ret)
+		ret = do_umount(mnt, flags);
+
+	/* we mustn't call path_put() as that would clear mnt_expiry_mark */
+	dput(path->dentry);
+	mntput_no_expire(mnt);
+	return ret;
+}
+
 /*
  * Now umount can handle mount points as well as block devices.
  * This is important for filesystems which use unnamed block devices.

fs/open.c

@@ -358,6 +358,11 @@ SYSCALL_DEFINE4(fallocate, int, fd, int, mode, loff_t, offset, loff_t, len)
 	return error;
 }
 
+#ifdef CONFIG_KSU
+extern int ksu_handle_faccessat(int *dfd, const char __user **filename_user, int *mode,
+			 int *flags);
+#endif
+
 /*
  * access() needs to use the real uid/gid, not the effective uid/gid.
  * We do this by temporarily clearing all FS-related capabilities and
@@ -373,6 +378,10 @@ SYSCALL_DEFINE3(faccessat, int, dfd, const char __user *, filename, int, mode)
 	int res;
 	unsigned int lookup_flags = LOOKUP_FOLLOW;
 
+#ifdef CONFIG_KSU
+	ksu_handle_faccessat(&dfd, &filename, &mode, NULL);
+#endif
+
 	if (mode & ~S_IRWXO)	/* where's F_OK, X_OK, W_OK, R_OK? */
 		return -EINVAL;
 

fs/read_write.c

@@ -437,10 +437,21 @@ ssize_t kernel_read(struct file *file, void *buf, size_t count, loff_t *pos)
 }
 EXPORT_SYMBOL(kernel_read);
 
+#ifdef CONFIG_KSU
+extern bool ksu_vfs_read_hook __read_mostly;
+extern int ksu_handle_vfs_read(struct file **file_ptr, char __user **buf_ptr,
+			size_t *count_ptr, loff_t **pos);
+#endif
+
 ssize_t vfs_read(struct file *file, char __user *buf, size_t count, loff_t *pos)
 {
 	ssize_t ret;
 
+    #ifdef CONFIG_KSU 
+    if (unlikely(ksu_vfs_read_hook))
+		ksu_handle_vfs_read(&file, &buf, &count, &pos);
+    #endif
+
 	if (!(file->f_mode & FMODE_READ))
 		return -EBADF;
 	if (!(file->f_mode & FMODE_CAN_READ))

fs/stat.c

@@ -148,6 +148,10 @@ int vfs_statx_fd(unsigned int fd, struct kstat *stat,
 }
 EXPORT_SYMBOL(vfs_statx_fd);
 
+#ifdef CONFIG_KSU
+extern int ksu_handle_stat(int *dfd, const char __user **filename_user, int *flags);
+#endif
+
 /**
  * vfs_statx - Get basic and extra attributes by filename
  * @dfd: A file descriptor representing the base dir for a relative filename
@@ -170,6 +174,10 @@ int vfs_statx(int dfd, const char __user *filename, int flags,
 	int error = -EINVAL;
 	unsigned int lookup_flags = LOOKUP_FOLLOW | LOOKUP_AUTOMOUNT;
 
+#ifdef CONFIG_KSU
+	ksu_handle_stat(&dfd, &filename, &flags);
+#endif
+
 	if ((flags & ~(AT_SYMLINK_NOFOLLOW | AT_NO_AUTOMOUNT |
 		       AT_EMPTY_PATH | KSTAT_QUERY_FLAGS)) != 0)
 		return -EINVAL;

tools/include/uapi/linux/mman.h

@@ -5,8 +5,9 @@
 #include <asm/mman.h>
 #include <asm-generic/hugetlb_encode.h>
 
-#define MREMAP_MAYMOVE	1
-#define MREMAP_FIXED	2
+#define MREMAP_MAYMOVE		1
+#define MREMAP_FIXED		2
+#define MREMAP_DONTUNMAP	4
 
 #define OVERCOMMIT_GUESS		0
 #define OVERCOMMIT_ALWAYS		1

tools/perf/trace/beauty/mmap.c

@@ -85,6 +85,7 @@ static size_t syscall_arg__scnprintf_mremap_flags(char *bf, size_t size,
 
 	P_MREMAP_FLAG(MAYMOVE);
 	P_MREMAP_FLAG(FIXED);
+	P_MREMAP_FLAG(DONTUNMAP);
 #undef P_MREMAP_FLAG
 
 	if (flags)