f2fs: enhance to update i_mode and acl atomically in f2fs_setattr()

[ Upstream commit 17232e830afb800acdcc22ae8980bf9d330393ef ]

Previously, in f2fs_setattr(), we don't update S_ISUID|S_ISGID|S_ISVTX
bits with S_IRWXUGO bits and acl entries atomically, so in error path,
chmod() may partially success, this patch enhances to make chmod() flow
being atomical.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Stable-dep-of: aaf8c0b9ae04 ("f2fs: reduce expensive checkpoint trigger frequency")
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Chao Yu 2020-12-25 16:52:27 +08:00 committed by Greg Kroah-Hartman
parent 0f1d007bbe
commit 7b5476f061
3 changed files with 35 additions and 9 deletions

View File

@ -200,6 +200,27 @@ struct posix_acl *f2fs_get_acl(struct inode *inode, int type)
return __f2fs_get_acl(inode, type, NULL);
}
static int f2fs_acl_update_mode(struct inode *inode, umode_t *mode_p,
struct posix_acl **acl)
{
umode_t mode = inode->i_mode;
int error;
if (is_inode_flag_set(inode, FI_ACL_MODE))
mode = F2FS_I(inode)->i_acl_mode;
error = posix_acl_equiv_mode(*acl, &mode);
if (error < 0)
return error;
if (error == 0)
*acl = NULL;
if (!in_group_p(inode->i_gid) &&
!capable_wrt_inode_uidgid(inode, CAP_FSETID))
mode &= ~S_ISGID;
*mode_p = mode;
return 0;
}
static int __f2fs_set_acl(struct inode *inode, int type,
struct posix_acl *acl, struct page *ipage)
{
@ -213,7 +234,7 @@ static int __f2fs_set_acl(struct inode *inode, int type,
case ACL_TYPE_ACCESS:
name_index = F2FS_XATTR_INDEX_POSIX_ACL_ACCESS;
if (acl && !ipage) {
error = posix_acl_update_mode(inode, &mode, &acl);
error = f2fs_acl_update_mode(inode, &mode, &acl);
if (error)
return error;
set_acl_inode(inode, mode);

View File

@ -980,8 +980,10 @@ int f2fs_setattr(struct dentry *dentry, struct iattr *attr)
if (attr->ia_valid & ATTR_MODE) {
err = posix_acl_chmod(inode, f2fs_get_inode_mode(inode));
if (err || is_inode_flag_set(inode, FI_ACL_MODE)) {
inode->i_mode = F2FS_I(inode)->i_acl_mode;
if (is_inode_flag_set(inode, FI_ACL_MODE)) {
if (!err)
inode->i_mode = F2FS_I(inode)->i_acl_mode;
clear_inode_flag(inode, FI_ACL_MODE);
}
}

View File

@ -673,7 +673,7 @@ static int __f2fs_setxattr(struct inode *inode, int index,
}
if (value && f2fs_xattr_value_same(here, value, size))
goto exit;
goto same;
} else if ((flags & XATTR_REPLACE)) {
error = -ENODATA;
goto exit;
@ -753,17 +753,20 @@ static int __f2fs_setxattr(struct inode *inode, int index,
if (error)
goto exit;
if (is_inode_flag_set(inode, FI_ACL_MODE)) {
inode->i_mode = F2FS_I(inode)->i_acl_mode;
inode->i_ctime = current_time(inode);
clear_inode_flag(inode, FI_ACL_MODE);
}
if (index == F2FS_XATTR_INDEX_ENCRYPTION &&
!strcmp(name, F2FS_XATTR_NAME_ENCRYPTION_CONTEXT))
f2fs_set_encrypted_inode(inode);
f2fs_mark_inode_dirty_sync(inode, true);
if (!error && S_ISDIR(inode->i_mode))
set_sbi_flag(F2FS_I_SB(inode), SBI_NEED_CP);
same:
if (is_inode_flag_set(inode, FI_ACL_MODE)) {
inode->i_mode = F2FS_I(inode)->i_acl_mode;
inode->i_ctime = current_time(inode);
clear_inode_flag(inode, FI_ACL_MODE);
}
exit:
kfree(base_addr);
return error;