[PATCH 17/24] init: add an init_chown helper
From: Christoph Hellwig <hch@lst.de>
Date: 2020-07-21 16:29:49
Also in:
linux-fsdevel, linux-raid, lkml
Subsystem:
filesystems (vfs and infrastructure), the rest · Maintainers:
Alexander Viro, Christian Brauner, Linus Torvalds
Add a simple helper to chown with a kernel space file name and switch the early init code over to it. Signed-off-by: Christoph Hellwig <hch@lst.de> --- fs/internal.h | 2 +- fs/open.c | 2 +- init/do_mounts.h | 1 + init/fs.c | 18 ++++++++++++++++++ init/initramfs.c | 6 +++--- 5 files changed, 24 insertions(+), 5 deletions(-)
diff --git a/fs/internal.h b/fs/internal.h
index e903d5aae139a2..4a66730fabefa7 100644
--- a/fs/internal.h
+++ b/fs/internal.h@@ -129,7 +129,7 @@ long do_sys_ftruncate(unsigned int fd, loff_t length, int small); int do_fchmodat(int dfd, const char __user *filename, umode_t mode); int do_fchownat(int dfd, const char __user *filename, uid_t user, gid_t group, int flag); - +int chown_common(const struct path *path, uid_t user, gid_t group); extern int vfs_open(const struct path *, struct file *); /*
diff --git a/fs/open.c b/fs/open.c
index f62f4752bb436d..49960a1248f14b 100644
--- a/fs/open.c
+++ b/fs/open.c@@ -639,7 +639,7 @@ SYSCALL_DEFINE2(chmod, const char __user *, filename, umode_t, mode) return do_fchmodat(AT_FDCWD, filename, mode); } -static int chown_common(const struct path *path, uid_t user, gid_t group) +int chown_common(const struct path *path, uid_t user, gid_t group) { struct inode *inode = path->dentry->d_inode; struct inode *delegated_inode = NULL;
diff --git a/init/do_mounts.h b/init/do_mounts.h
index 810b37ce1db882..db42564080a2f9 100644
--- a/init/do_mounts.h
+++ b/init/do_mounts.h@@ -13,6 +13,7 @@ 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_chdir(const char *filename); int __init init_chroot(const char *filename); +int __init init_chown(const char *filename, uid_t user, gid_t group, int flags); int __init init_unlink(const char *pathname); int __init init_rmdir(const char *pathname);
diff --git a/init/fs.c b/init/fs.c
index af55e6d40357dc..30000b7097b9f0 100644
--- a/init/fs.c
+++ b/init/fs.c@@ -59,6 +59,24 @@ int __init init_chroot(const char *filename) return error; } +int __init init_chown(const char *filename, uid_t user, gid_t group, int flags) +{ + int lookup_flags = (flags & AT_SYMLINK_NOFOLLOW) ? 0 : LOOKUP_FOLLOW; + struct path path; + int error; + + error = kern_path(filename, lookup_flags, &path); + if (error) + return error; + error = mnt_want_write(path.mnt); + if (!error) { + error = chown_common(&path, user, group); + mnt_drop_write(path.mnt); + } + path_put(&path); + return error; +} + int __init init_unlink(const char *pathname) { return do_unlinkat(AT_FDCWD, getname_kernel(pathname));
diff --git a/init/initramfs.c b/init/initramfs.c
index 41491149fb1f29..076413dbe8bcf3 100644
--- a/init/initramfs.c
+++ b/init/initramfs.c@@ -353,14 +353,14 @@ static int __init do_name(void) } } else if (S_ISDIR(mode)) { ksys_mkdir(collected, mode); - ksys_chown(collected, uid, gid); + init_chown(collected, uid, gid, 0); ksys_chmod(collected, mode); dir_add(collected, mtime); } else if (S_ISBLK(mode) || S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) { if (maybe_link() == 0) { ksys_mknod(collected, mode, rdev); - ksys_chown(collected, uid, gid); + init_chown(collected, uid, gid, AT_SYMLINK_NOFOLLOW); ksys_chmod(collected, mode); do_utime(collected, mtime); }
@@ -398,7 +398,7 @@ static int __init do_symlink(void) collected[N_ALIGN(name_len) + body_len] = '\0'; clean_path(collected, 0); ksys_symlink(collected + N_ALIGN(name_len), collected); - ksys_lchown(collected, uid, gid); + init_chown(collected, uid, gid, AT_SYMLINK_NOFOLLOW); do_utime(collected, mtime); state = SkipIt; next_state = Reset;
--
2.27.0