linux-kernel - Re: [f2fs-dev] [PATCH] f2fs: add F2FS_IOC_SEC_TRIM

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <CACOAw_x3yC8ELYj7qSC7PM2RwpYRwQu7mT1vJhoFUQX4uzx2=w@mail.gmail.com>
Date:   Thu, 11 Jun 2020 11:05:12 +0900
From:   Daeho Jeong <daeho43@...il.com>
To:     Eric Biggers <ebiggers@...nel.org>
Cc:     linux-kernel@...r.kernel.org,
        linux-f2fs-devel@...ts.sourceforge.net, kernel-team@...roid.com,
        Daeho Jeong <daehojeong@...gle.com>
Subject: Re: [f2fs-dev] [PATCH] f2fs: add F2FS_IOC_SEC_TRIM_FILE ioctl

Ok, I got it. Thanks for quick response~ :)

2020년 6월 11일 (목) 오전 10:56, Eric Biggers <ebiggers@...nel.org>님이 작성:
>
> On Thu, Jun 11, 2020 at 09:23:23AM +0900, Daeho Jeong wrote:
> > Yes, I saw the implementation in vfs_write().
> > But if we use mnt_want_write_file() here, it'll call mnt_clone_write()
> > internally if the file is already open in write mode.
> > Don't you think the below thing is needed? We can increase the counter
> > each of them, open and ioctl, like other filesystems such as ext4.
> >
> > int mnt_clone_write(struct vfsmount *mnt)
> > {
> >         /* superblock may be r/o */
> >         if (__mnt_is_readonly(mnt))
> >                 return -EROFS;
> >         preempt_disable();
> >         mnt_inc_writers(real_mount(mnt));
> >         preempt_enable();
> >         return 0;
> > }
>
> No, this seems to be left over from when mnt_want_write_file() was paired with
> mnt_drop_write() instead of mnt_drop_write_file().  I sent a patch to remove it:
> https://lkml.kernel.org/r/20200611014945.237210-1-ebiggers@kernel.org
>
> - Eric