On Thu, 2 Apr 2026 at 19:05, Dan Carpenter <[email protected]> wrote: > > On Thu, Apr 02, 2026 at 03:48:20PM +0200, Marco Elver wrote: > > On Thu, 2 Apr 2026 at 15:33, Dan Carpenter <[email protected]> wrote: > > > > > > Hi Marco, > > > > > > kernel test robot noticed the following build warnings: > > > > > > https://git-scm.com/docs/git-format-patch#_base_tree_information] > > > > > > url: > > > https://github.com/intel-lab-lkp/linux/commits/Marco-Elver/slab-support-for-compiler-assisted-type-based-slab-cache-partitioning/20260401-035608 > > > base: https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git > > > mm-everything > > > patch link: > > > https://lore.kernel.org/r/20260331111240.153913-1-elver%40google.com > > > patch subject: [PATCH v1] slab: support for compiler-assisted type-based > > > slab cache partitioning > > > config: um-randconfig-r072-20260401 > > > compiler: gcc-14 (Debian 14.2.0-19) 14.2.0 > > > smatch: v0.5.0-9004-gb810ac53 > > > > > > If you fix the issue in a separate patch/commit (i.e. not just a new > > > version of > > > the same patch/commit), kindly add following tags > > > | Reported-by: kernel test robot <[email protected]> > > > | Reported-by: Dan Carpenter <[email protected]> > > > | Closes: https://lore.kernel.org/r/[email protected]/ > > > > > > New smatch warnings: > > > drivers/misc/lkdtm/heap.c:118 lkdtm_READ_AFTER_FREE() warn: potential > > > pointer math issue ('base' is a 32 bit pointer) > > > drivers/misc/lkdtm/heap.c:169 lkdtm_KFENCE_READ_AFTER_FREE() warn: > > > potential pointer math issue ('base' is a 32 bit pointer) > > > > How is this related to the patch I sent? Did the <linux/slab.h> change > > force rechecking of all these files and it found latent issues? > > > > Oh, crud. It turns out that for this check Smatch allows > integer_array[sizeof()]so long as we know that the index is within > bounds. What happened is that your patch renamed the kmalloc() > function so Smatch stopped knowing the size of the buffer.
Oh, I see. Smatch doesn't respect the __alloc_size attribute then? > For these zero day bot warnings, the emails are automatically generated > so I don't have any context outside what's in the email. I saw that > Kees wrote the code, but I figured maybe you forwarded it or something. > Sorry about that. No worries and thanks!
