Re: [PATCH AUTOSEL 5.8 14/29] regmap: debugfs: Fix handling of name string for debugfs init delays

From: Charles Keepax
Date: Tue Sep 29 2020 - 04:33:42 EST


On Mon, Sep 28, 2020 at 09:30:11PM -0400, Sasha Levin wrote:
> From: Charles Keepax <ckeepax@xxxxxxxxxxxxxxxxxxxxx>
>
> [ Upstream commit 94cc89eb8fa5039fcb6e3e3d50f929ddcccee095 ]
>
> In regmap_debugfs_init the initialisation of the debugfs is delayed
> if the root node isn't ready yet. Most callers of regmap_debugfs_init
> pass the name from the regmap_config, which is considered temporary
> ie. may be unallocated after the regmap_init call returns. This leads
> to a potential use after free, where config->name has been freed by
> the time it is used in regmap_debugfs_initcall.
>

Afraid this patch had some issues if you are back porting it you
definitely need to take these two patches as well:

commit 1d512ee861b80da63cbc501b973c53131aa22f29
regmap: debugfs: Fix more error path regressions

commit d36cb0205f034e943aa29e35b59c6a441f0056b5
regmap: debugfs: Add back in erroneously removed initialisation of ret

Thanks,
Charles