Re: [PATCH v3 1/3] slab: make check_object() more consistent

From: Christoph Lameter (Ampere)
Date: Mon Jun 10 2024 - 13:31:50 EST


On Fri, 7 Jun 2024, Chengming Zhou wrote:

There are two inconsistencies in check_object(), which are alignment
padding checking and object padding checking. We only print the error
messages but don't return 0 to tell callers that something is wrong
and needs to be handled. Please see alloc_debug_processing() and
free_debug_processing() for details.

If the error is in the padding and the redzones are ok then its likely that the objects are ok. So we can actually continue with this slab page instead of isolating it.

We isolate it in the case that the redzones have been violated because that suggests someone overwrote the end of the object f.e. In that case objects may be corrupted. Its best to isolate the slab and hope for the best.

If it was just the padding then the assumption is that this may be a scribble. So clean it up and continue.