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Date:   Thu, 28 Jul 2022 18:57:44 +0800
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Subject: Re: [PATCH] xfs: fix NULL pointer dereference in xfs_getbmap()
To:     "Darrick J. Wong" <djwong@kernel.org>
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在 2022/7/27 23:16, Darrick J. Wong 写道:

> Heh.  Is this worth an fstest?  It probably is, since prior to 5.20 this
> would have been a UAF bug on top of a NULL deref.

I will try to add regression test to xfstests for this commit when it is 
merged into mainline.

> 
> Nit: it's ILOCK, not i_lock.  Otherwise... this looks correct to me --
> take the IOLOCK and ILOCK in shared mode before accessing the inode fork
> structures.
> 
> Do you have any suggestions for Fixes:?  I suspect this has been broken
> for quite some time.

The "Fixes:" label is: abbf9e8a4507 ("xfs: rewrite getbmap using the 
xfs_iext_* helpers")

> 
> No need to fix the nit, I'll do that when I commit this.
> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
> 
> --D
>