On Mon, Oct 14, 2024 at 10:20:36PM +0800, Feng Tang wrote: > On Mon, Oct 14, 2024 at 03:12:09PM +0200, Vlastimil Babka wrote: > > On 10/14/24 14:52, Feng Tang wrote: > > > On Mon, Oct 14, 2024 at 10:53:32AM +0200, Vlastimil Babka wrote: > > >> On 10/14/24 09:52, Feng Tang wrote: > > > OK, originally I tried not to expose internals of __ksize(). Let me > > > try this way. > > > > ksize() makes assumptions that a user outside of slab itself is calling it. > > > > But we (well mostly Kees) also introduced kmalloc_size_roundup() to avoid > > querying ksize() for the purposes of writing beyond the original > > kmalloc(size) up to the bucket size. So maybe we can also investigate if the > > skip_orig_size_check() mechanism can be removed now? > > I did a quick grep, and fortunately it seems that the ksize() user are > much less than before. We used to see some trouble in network code, which > is now very clean without the need to skip orig_size check. Will check > other call site later. Right -- only things that are performing a reallocation should be using ksize(). e.g. see __slab_build_skb() -- Kees Cook
