Add a simple helper perform a mkdir with a kernel space file name and use it in the early init code instead of relying on the implicit set_fs(KERNEL_DS) there. To do so push the getname from do_mkdirat into the callers. Remove the now unused ksys_mkdir. Signed-off-by: Christoph Hellwig <hch@xxxxxx> --- fs/internal.h | 1 - fs/namei.c | 14 ++++++++++---- include/linux/fs.h | 1 + include/linux/syscalls.h | 7 ------- init/do_mounts_initrd.c | 2 +- init/initramfs.c | 2 +- init/noinitramfs.c | 4 ++-- 7 files changed, 15 insertions(+), 16 deletions(-) diff --git a/fs/internal.h b/fs/internal.h index 1e2b425f56ee9e..722d33a66d9645 100644 --- a/fs/internal.h +++ b/fs/internal.h @@ -64,7 +64,6 @@ extern int vfs_path_lookup(struct dentry *, struct vfsmount *, const char *, unsigned int, struct path *); long do_mknodat(int dfd, const char __user *filename, umode_t mode, unsigned int dev); -long do_mkdirat(int dfd, const char __user *pathname, umode_t mode); long do_rmdir(int dfd, const char __user *pathname); long do_unlinkat(int dfd, struct filename *name); long do_symlinkat(const char __user *oldname, int newdfd, diff --git a/fs/namei.c b/fs/namei.c index 6daffd59e97270..3545623495d1f4 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -3665,7 +3665,7 @@ int vfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) } EXPORT_SYMBOL(vfs_mkdir); -long do_mkdirat(int dfd, const char __user *pathname, umode_t mode) +static int do_mkdirat(int dfd, struct filename *name, umode_t mode) { struct dentry *dentry; struct path path; @@ -3673,7 +3673,7 @@ long do_mkdirat(int dfd, const char __user *pathname, umode_t mode) unsigned int lookup_flags = LOOKUP_DIRECTORY; retry: - dentry = user_path_create(dfd, pathname, &path, lookup_flags); + dentry = filename_create(dfd, name, &path, lookup_flags); if (IS_ERR(dentry)) return PTR_ERR(dentry); @@ -3687,17 +3687,23 @@ long do_mkdirat(int dfd, const char __user *pathname, umode_t mode) lookup_flags |= LOOKUP_REVAL; goto retry; } + putname(name); return error; } +int kern_mkdir(const char *pathname, umode_t mode) +{ + return do_mkdirat(AT_FDCWD, getname_kernel(pathname), mode); +} + SYSCALL_DEFINE3(mkdirat, int, dfd, const char __user *, pathname, umode_t, mode) { - return do_mkdirat(dfd, pathname, mode); + return do_mkdirat(dfd, getname(pathname), mode); } SYSCALL_DEFINE2(mkdir, const char __user *, pathname, umode_t, mode) { - return do_mkdirat(AT_FDCWD, pathname, mode); + return do_mkdirat(AT_FDCWD, getname(pathname), mode); } int vfs_rmdir(struct inode *dir, struct dentry *dentry) diff --git a/include/linux/fs.h b/include/linux/fs.h index 7472ff0b7062d9..3bbeeadf2ddd98 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -3677,5 +3677,6 @@ int __init kern_access(const char *filename, int mode); int __init kern_chown(const char *filename, uid_t user, gid_t group, int flag); int __init kern_chmod(const char *filename, umode_t mode); int __init kern_utimes(const char *filename, struct timespec64 *tv, int flags); +int kern_mkdir(const char *pathname, umode_t mode); #endif /* _LINUX_FS_H */ diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h index a2ece4cc8692f5..6aa1cd200425a4 100644 --- a/include/linux/syscalls.h +++ b/include/linux/syscalls.h @@ -1284,13 +1284,6 @@ static inline long ksys_rmdir(const char __user *pathname) return do_rmdir(AT_FDCWD, pathname); } -extern long do_mkdirat(int dfd, const char __user *pathname, umode_t mode); - -static inline long ksys_mkdir(const char __user *pathname, umode_t mode) -{ - return do_mkdirat(AT_FDCWD, pathname, mode); -} - extern long do_symlinkat(const char __user *oldname, int newdfd, const char __user *newname); diff --git a/init/do_mounts_initrd.c b/init/do_mounts_initrd.c index 1cbc9988d2e0ad..b9a749ebe85c2d 100644 --- a/init/do_mounts_initrd.c +++ b/init/do_mounts_initrd.c @@ -81,7 +81,7 @@ static void __init handle_initrd(void) create_dev("/dev/root.old", Root_RAM0); /* mount initrd on rootfs' /root */ mount_block_root("/dev/root.old", root_mountflags & ~MS_RDONLY); - ksys_mkdir("/old", 0700); + kern_mkdir("/old", 0700); kern_chdir("/old"); /* diff --git a/init/initramfs.c b/init/initramfs.c index de850d4c6da200..40b97ca5fe8cde 100644 --- a/init/initramfs.c +++ b/init/initramfs.c @@ -344,7 +344,7 @@ static int __init do_name(void) state = CopyFile; } } else if (S_ISDIR(mode)) { - ksys_mkdir(collected, mode); + kern_mkdir(collected, mode); kern_chown(collected, uid, gid, 0); kern_chmod(collected, mode); dir_add(collected, mtime); diff --git a/init/noinitramfs.c b/init/noinitramfs.c index fa9cdfa7101d3c..89109c1d633adb 100644 --- a/init/noinitramfs.c +++ b/init/noinitramfs.c @@ -17,7 +17,7 @@ static int __init default_rootfs(void) { int err; - err = ksys_mkdir((const char __user __force *) "/dev", 0755); + err = kern_mkdir("/dev", 0755); if (err < 0) goto out; @@ -27,7 +27,7 @@ static int __init default_rootfs(void) if (err < 0) goto out; - err = ksys_mkdir((const char __user __force *) "/root", 0700); + err = kern_mkdir("/root", 0700); if (err < 0) goto out; -- 2.27.0