Re: [PATCH] fs/ntfs: fix BUG_ON of ntfs_read_block()

[CGEL <cgel.zte@gmail.com>]

On Thu, Jun 23, 2022 at 09:57:39AM +0200, Greg KH wrote:
> On Thu, Jun 23, 2022 at 03:51:31AM +0000, cgel.zte@gmail.com wrote:
> > From: xu xin <xu.xin16@zte.com.cn>
> > 
> > As the bug description, attckers can use this bug to crash the system
> > When CONFIG_NTFS_FS is set.
> > 
> > So remove the BUG_ON, and use WARN and return instead until someone
> > really solve the bug.
> > 
> > Reported-by: Zeal Robot <zealci@zte.com.cn>
> > Reported-by: syzbot+6a5a7672f663cce8b156@syzkaller.appspotmail.com
> > Reviewed-by: Songyi Zhang <zhang.songyi@zte.com.cn>
> > Reviewed-by: Yang Yang <yang.yang29@zte.com.cn>
> > Reviewed-by: Jiang Xuexin<jiang.xuexin@zte.com.cn>
> > Reviewed-by: Zhang wenya<zhang.wenya1@zte.com.cn>
> > Signed-off-by: xu xin <xu.xin16@zte.com.cn>
> > ---
> >  fs/ntfs/aops.c | 6 +++++-
> >  1 file changed, 5 insertions(+), 1 deletion(-)
> > 
> > --- a/fs/ntfs/aops.c
> > +++ b/fs/ntfs/aops.c
> > @@ -183,7 +183,11 @@ static int ntfs_read_block(struct page *page)
> >  	vol = ni->vol;
> >  
> >  	/* $MFT/$DATA must have its complete runlist in memory at all times. */
> > -	BUG_ON(!ni->runlist.rl && !ni->mft_no && !NInoAttr(ni));
> > +	if (unlikely(!ni->runlist.rl && !ni->mft_no && !NInoAttr(ni))) {
> > +		WARN(1, "NTFS: ni->runlist.rl, ni->mft_no, and NInoAttr(ni) is null!\n");
> > +		unlock_page(page);
> > +		return -EINVAL;
> > +	}
> >  
> >  	blocksize = vol->sb->s_blocksize;
> >  	blocksize_bits = vol->sb->s_blocksize_bits;
> > -- 
> > 2.25.1
> > 
> 
> <formletter>
> 
> This is not the correct way to submit patches for inclusion in the
> stable kernel tree.  Please read:
>     https://www.kernel.org/doc/html/latest/process/stable-kernel-rules.html
> for how to do this properly.
>

Sorry. I'll rewrite a patch to fix it. 

Thanks.

> </formletter>