Re: [PATCH AUTOSEL 4.19 174/258] livepatch: check kzalloc return values

[Sasha Levin]

On Mon, Jan 28, 2019 at 06:28:14PM +0100, Miroslav Benes wrote:
> On Mon, 28 Jan 2019, Sasha Levin wrote:
>
> > From: Nicholas Mc Guire <hofrat@xxxxxxxxx>
> >
> > [ Upstream commit 5f30b2e823484ce6a79f2b59901b6351c15effa6 ]
> >
> > kzalloc() return should always be checked - notably in example code
> > where this may be seen as reference. On failure of allocation in
> > livepatch_fix1_dummy_alloc() respectively dummy_alloc() previous
> > allocation is freed (thanks to Petr Mladek <pmladek@xxxxxxxx> for
> > catching this) and NULL returned.
> >
> > Signed-off-by: Nicholas Mc Guire <hofrat@xxxxxxxxx>
> > Fixes: 439e7271dc2b ("livepatch: introduce shadow variable API")
> > Acked-by: Joe Lawrence <joe.lawrence@xxxxxxxxxx>
> > Reviewed-by: Petr Mladek <pmladek@xxxxxxxx>
> > Acked-by: Miroslav Benes <mbenes@xxxxxxx>
> > Signed-off-by: Jiri Kosina <jkosina@xxxxxxx>
> > Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
>
> Hi Sasha,
>
> I am not sure what stable policy is, but the patch is for samples/
> directory and I do not think it is something which should necessarily go
> to stable. It is your call though.

The thing with samples/ is that (I'm hopefull that) the code that lives
in there is being used as a basis for userspace code and is copy&pasted
shamelessly.

So on one hand, yes, samples/ isn't exactly critical code, but on the
other hand it's also very unlikely to cause a regression, so I've been
treating it similarily to tools/testing/.

If anyone disagrees I'd be happy to discuss it.

--
Thanks,
Sasha