Re: [PATCH] btrfs: sysfs: Handle NULL return values

[Kees Cook]

On Sun, Feb 05, 2023 at 08:13:30AM +0100, Greg KH wrote:
> On Sat, Feb 04, 2023 at 10:35:10AM -0800, Kees Cook wrote:
> > Each of to_fs_info(), discard_to_fs_info(), and to_space_info() can
> > return NULL values.
> 
> The code says it could, but I really do not think that is possible at
> all, especially based on the fact that there have never been any crashes
> reported here.

I'm not sure that's a useful measure if we're trying to improve
robustness under memory corruption, but at least one of those helpers is
performing a type check, not just a simple container_of(), etc.

Regardless, yeah, if this can be done without NULL returns, sure, let's
do it. I just don't know this code well enough to say what's possible.
:)

-- 
Kees Cook