Re: [PATCH v4] hfs: Validate CNIDs in hfs_read_inode

[George Anthony Vernon]

Sorry I struggled to understand you here Slava, there's a little bit lost in
translation I think.

On Mon, Mar 16, 2026 at 09:50:14PM +0000, Viacheslav Dubeyko wrote:
> by hfs_cat_find_brec(). But I cannot imagine that this logic can extract the
> record  with incorrect CNID. Because, it is the main goal of hfs_cat_find_brec()
> logic to extract the record that contains requested CNID. And if we requested

Do you mean that you do not think hfs_cat_find_brec *can* return a
record with incorrect CNID, or that you do not think it *should*?

I think Tetsuo is right that hfs_cat_find_brec() will return a catalog
record with different CNID in case of a malformed thread record.

On Mon, Mar 16, 2026 at 09:50:14PM +0000, Viacheslav Dubeyko wrote:
> logic to extract the record that contains requested CNID. And if we requested
> the HFS_ROOT_CNID, then this logic should return the record with exactly
> requested CNID or return the error code if such record has not been found.

Do you mean that hfs_cat_find_brec() should validate the CNID of the
catalog record found by hfs_brec_find()? I'm worried that validating
every B-tree lookup is going to be expensive. We could do it, however.

Thanks,

George