diff --git a/drivers/base/devtmpfs.c b/drivers/base/devtmpfs.c index 32af6cb987b4287496c5df0738074de7b4ec4ea3..e48aaba3166b5d45e604658ac51e169a99d6a292 100644 --- a/drivers/base/devtmpfs.c +++ b/drivers/base/devtmpfs.c @@ -412,7 +412,7 @@ static int __init devtmpfs_setup(void *p) err = init_mount("devtmpfs", "/", "devtmpfs", MS_SILENT, NULL); if (err) goto out; - ksys_chdir("/.."); /* will traverse into overmounted root */ + init_chdir("/.."); /* will traverse into overmounted root */ ksys_chroot("."); out: *(int *)p = err; diff --git a/fs/init.c b/fs/init.c index eabd9ed2b51092cdaf54dca72946d9df1ea132d8..64d4e12eba933946f3330fee70d5650960e5bcb5 100644 --- a/fs/init.c +++ b/fs/init.c @@ -7,6 +7,7 @@ #include #include #include +#include #include #include "internal.h" @@ -38,6 +39,21 @@ int __init init_umount(const char *name, int flags) return path_umount(&path, flags); } +int __init init_chdir(const char *filename) +{ + struct path path; + int error; + + error = kern_path(filename, LOOKUP_FOLLOW | LOOKUP_DIRECTORY, &path); + if (error) + return error; + error = inode_permission(path.dentry->d_inode, MAY_EXEC | MAY_CHDIR); + if (!error) + set_fs_pwd(current->fs, &path); + path_put(&path); + return error; +} + int __init init_unlink(const char *pathname) { return do_unlinkat(AT_FDCWD, getname_kernel(pathname)); diff --git a/fs/open.c b/fs/open.c index b316dd6a86a8b9f270eed0e0d77c3fb969a2bc5d..723e0ac898935e0c3a1f14de3a974641d497a4a4 100644 --- a/fs/open.c +++ b/fs/open.c @@ -482,7 +482,7 @@ SYSCALL_DEFINE2(access, const char __user *, filename, int, mode) return do_faccessat(AT_FDCWD, filename, mode, 0); } -int ksys_chdir(const char __user *filename) +SYSCALL_DEFINE1(chdir, const char __user *, filename) { struct path path; int error; @@ -508,11 +508,6 @@ int ksys_chdir(const char __user *filename) return error; } -SYSCALL_DEFINE1(chdir, const char __user *, filename) -{ - return ksys_chdir(filename); -} - SYSCALL_DEFINE1(fchdir, unsigned int, fd) { struct fd f = fdget_raw(fd); diff --git a/include/linux/init_syscalls.h b/include/linux/init_syscalls.h index abf3af563c0b3aff1d1d46eb3c514846d1a3f2ee..1e845910ae56e9b50bc023e4b94738af60ab7539 100644 --- a/include/linux/init_syscalls.h +++ b/include/linux/init_syscalls.h @@ -3,5 +3,6 @@ int __init init_mount(const char *dev_name, const char *dir_name, const char *type_page, unsigned long flags, void *data_page); int __init init_umount(const char *name, int flags); +int __init init_chdir(const char *filename); int __init init_unlink(const char *pathname); int __init init_rmdir(const char *pathname); diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h index a7b14258d245e245664cb4810cf0816ed2f2dbd8..31fa67fb9894b32e403a997d3fe6906af4245863 100644 --- a/include/linux/syscalls.h +++ b/include/linux/syscalls.h @@ -1238,7 +1238,6 @@ asmlinkage long sys_ni_syscall(void); int ksys_chroot(const char __user *filename); ssize_t ksys_write(unsigned int fd, const char __user *buf, size_t count); -int ksys_chdir(const char __user *filename); int ksys_fchown(unsigned int fd, uid_t user, gid_t group); ssize_t ksys_read(unsigned int fd, char __user *buf, size_t count); void ksys_sync(void); diff --git a/init/do_mounts.c b/init/do_mounts.c index 83db87b6e5d1e0a056f7bf5f470768e8b542a942..a7581c6e85f2686ae5b1d6f8dd3113d93b42381e 100644 --- a/init/do_mounts.c +++ b/init/do_mounts.c @@ -408,7 +408,7 @@ static int __init do_mount_root(const char *name, const char *fs, if (ret) goto out; - ksys_chdir("/root"); + init_chdir("/root"); s = current->fs->pwd.dentry->d_sb; ROOT_DEV = s->s_dev; printk(KERN_INFO diff --git a/init/do_mounts_initrd.c b/init/do_mounts_initrd.c index 8b44dd017842a8929d7893a37b53eacae4ed6d0e..04627fd22a921fac08854c30b1fa0cf53a171648 100644 --- a/init/do_mounts_initrd.c +++ b/init/do_mounts_initrd.c @@ -61,7 +61,7 @@ static int __init init_linuxrc(struct subprocess_info *info, struct cred *new) ksys_unshare(CLONE_FS | CLONE_FILES); console_on_rootfs(); /* move initrd over / and chdir/chroot in initrd root */ - ksys_chdir("/root"); + init_chdir("/root"); init_mount(".", "/", NULL, MS_MOVE, NULL); ksys_chroot("."); ksys_setsid(); @@ -82,7 +82,7 @@ static void __init handle_initrd(void) /* mount initrd on rootfs' /root */ mount_block_root("/dev/root.old", root_mountflags & ~MS_RDONLY); ksys_mkdir("/old", 0700); - ksys_chdir("/old"); + init_chdir("/old"); /* * In case that a resume from disk is carried out by linuxrc or one of @@ -104,11 +104,11 @@ static void __init handle_initrd(void) ksys_chroot(".."); if (new_decode_dev(real_root_dev) == Root_RAM0) { - ksys_chdir("/old"); + init_chdir("/old"); return; } - ksys_chdir("/"); + init_chdir("/"); ROOT_DEV = new_decode_dev(real_root_dev); mount_root();