> 在 2018年9月12日，上午6:47，Jaegeuk Kim <jaegeuk@xxxxxxxxxx> 写道：
>
> On 09/11, Wang Shilong wrote:
>> From: Wang Shilong <wangshilong1991@xxxxxxxxx>
>>
>> Currently, project quota could be changed by fssetxattr
>> ioctl, and existed permission check inode_owner_or_capable()
>> is obviously not enough, just think that common users could
>> change project id of file, that could make users to
>> break project quota easily.
>>
>> This patch try to follow same regular of xfs project
>> quota:
>>
>> "Project Quota ID state is only allowed to change from
>> within the init namespace. Enforce that restriction only
>> if we are trying to change the quota ID state.
>> Everything else is allowed in user namespaces."
>>
>> Besides that, check and set project id'state should
>> be an atomic operation, protect whole operation with
>> inode lock.
>>
>> Signed-off-by: Wang Shilong <wshilong@xxxxxxx>
>> ---
>> v2->v3: remove inode_lock() and mnt_want_write_file()
>> inside f2fs_ioc_setproject()
>> v1->v2: rename f2fs_ioctl_setattr_check_projid()
>> to f2fs_ioctl_check_project()
>> fs/f2fs/file.c | 61 ++++++++++++++++++++++++++++++++++++----------------------
>> 1 file changed, 38 insertions(+), 23 deletions(-)
>>
>> diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
>> index 5474aaa..f5170e6 100644
>> --- a/fs/f2fs/file.c
>> +++ b/fs/f2fs/file.c
>> @@ -2617,34 +2617,26 @@ static int f2fs_ioc_setproject(struct file *filp, __u32 projid)
>> if (projid_eq(kprojid, F2FS_I(inode)->i_projid))
>> return 0;
>>
>> - err = mnt_want_write_file(filp);
>> - if (err)
>> - return err;
>> -
>> err = -EPERM;
>> - inode_lock(inode);
>> -
>> /* Is it quota file? Do not allow user to mess with it */
>> if (IS_NOQUOTA(inode))
>> - goto out_unlock;
>> + return err;
>>
>> ipage = f2fs_get_node_page(sbi, inode->i_ino);
>> - if (IS_ERR(ipage)) {
>> - err = PTR_ERR(ipage);
>> - goto out_unlock;
>> - }
>> + if (IS_ERR(ipage))
>> + return PTR_ERR(ipage);
>>
>> if (!F2FS_FITS_IN_INODE(F2FS_INODE(ipage), fi->i_extra_isize,
>> i_projid)) {
>> err = -EOVERFLOW;
>> f2fs_put_page(ipage, 1);
>> - goto out_unlock;
>> + return err;
>> }
>> f2fs_put_page(ipage, 1);
>>
>> err = dquot_initialize(inode);
>> if (err)
>> - goto out_unlock;
>> + return err;
>>
>> transfer_to[PRJQUOTA] = dqget(sb, make_kqid_projid(kprojid));
>> if (!IS_ERR(transfer_to[PRJQUOTA])) {
>> @@ -2658,9 +2650,6 @@ static int f2fs_ioc_setproject(struct file *filp, __u32 projid)
>> inode->i_ctime = current_time(inode);
>> out_dirty:
>> f2fs_mark_inode_dirty_sync(inode, true);
>> -out_unlock:
>> - inode_unlock(inode);
>> - mnt_drop_write_file(filp);
>> return err;
>> }
>> #else
>> @@ -2736,6 +2725,31 @@ static int f2fs_ioc_fsgetxattr(struct file *filp, unsigned long arg)
>> return 0;
>> }
>>
>> +static int
>> +f2fs_ioctl_check_project(struct inode *inode, struct fsxattr *fa)
>
> We're not following this coding style. Let me allow to declare like this.
>
> static int f2fs_ioctl_…
Hi JK,
Good point, I followed Lustre codes styles which was a bad
Example of this…LOL.
Thanks,
Shilong
>
> Thanks,
>
>> +{
>> + /*
>> + * Project Quota ID state is only allowed to change from within the init
>> + * namespace. Enforce that restriction only if we are trying to change
>> + * the quota ID state. Everything else is allowed in user namespaces.
>> + */
>> + if (current_user_ns() == &init_user_ns)
>> + return 0;
>> +
>> + if (__kprojid_val(F2FS_I(inode)->i_projid) != fa->fsx_projid)
>> + return -EINVAL;
>> +
>> + if (F2FS_I(inode)->i_flags & F2FS_PROJINHERIT_FL) {
>> + if (!(fa->fsx_xflags & FS_XFLAG_PROJINHERIT))
>> + return -EINVAL;
>> + } else {
>> + if (fa->fsx_xflags & FS_XFLAG_PROJINHERIT)
>> + return -EINVAL;
>> + }
>> +
>> + return 0;
>> +}
>> +
>> static int f2fs_ioc_fssetxattr(struct file *filp, unsigned long arg)
>> {
>> struct inode *inode = file_inode(filp);
>> @@ -2763,19 +2777,20 @@ static int f2fs_ioc_fssetxattr(struct file *filp, unsigned long arg)
>> return err;
>>
>> inode_lock(inode);
>> + err = f2fs_ioctl_check_project(inode, &fa);
>> + if (err)
>> + goto out;
>> flags = (fi->i_flags & ~F2FS_FL_XFLAG_VISIBLE) |
>> (flags & F2FS_FL_XFLAG_VISIBLE);
>> err = __f2fs_ioc_setflags(inode, flags);
>> - inode_unlock(inode);
>> - mnt_drop_write_file(filp);
>> if (err)
>> - return err;
>> + goto out;
>>
>> err = f2fs_ioc_setproject(filp, fa.fsx_projid);
>> - if (err)
>> - return err;
>> -
>> - return 0;
>> +out:
>> + inode_unlock(inode);
>> + mnt_drop_write_file(filp);
>> + return err;
>> }
>>
>> int f2fs_pin_file_control(struct inode *inode, bool inc)
>> --
>> 1.8.3.1
>>
>>
>>
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