Hello, On Thu, Sep 30, 2021 at 03:27:04PM -0700, Kees Cook wrote: > As already done in GrapheneOS, add the __alloc_size attribute for > appropriate percpu allocator interfaces, to provide additional hinting for > better bounds checking, assisting CONFIG_FORTIFY_SOURCE and other compiler > optimizations. > > Note that due to the implementation of the percpu API, this is unlikely > to ever actually provide compile-time checking beyond very simple non-SMP > builds. But, since they are technically allocators, mark them as such. > > Cc: Dennis Zhou <dennis@xxxxxxxxxx> > Cc: Tejun Heo <tj@xxxxxxxxxx> > Cc: Christoph Lameter <cl@xxxxxxxxx> > Cc: Andy Whitcroft <apw@xxxxxxxxxxxxx> > Cc: David Rientjes <rientjes@xxxxxxxxxx> > Cc: Dwaipayan Ray <dwaipayanray1@xxxxxxxxx> > Cc: Joe Perches <joe@xxxxxxxxxxx> > Cc: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx> > Cc: Lukas Bulwahn <lukas.bulwahn@xxxxxxxxx> > Cc: Miguel Ojeda <ojeda@xxxxxxxxxx> > Cc: Nathan Chancellor <nathan@xxxxxxxxxx> > Cc: Nick Desaulniers <ndesaulniers@xxxxxxxxxx> > Cc: Pekka Enberg <penberg@xxxxxxxxxx> > Cc: Vlastimil Babka <vbabka@xxxxxxx> > Co-developed-by: Daniel Micay <danielmicay@xxxxxxxxx> > Signed-off-by: Daniel Micay <danielmicay@xxxxxxxxx> > Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx> Thanks for updating the commit log. Acked-by: Dennis Zhou <dennis@xxxxxxxxxx> Thanks, Dennis > --- > include/linux/percpu.h | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/include/linux/percpu.h b/include/linux/percpu.h > index 5e76af742c80..98a9371133f8 100644 > --- a/include/linux/percpu.h > +++ b/include/linux/percpu.h > @@ -123,7 +123,7 @@ extern int __init pcpu_page_first_chunk(size_t reserved_size, > pcpu_fc_populate_pte_fn_t populate_pte_fn); > #endif > > -extern void __percpu *__alloc_reserved_percpu(size_t size, size_t align); > +extern void __percpu *__alloc_reserved_percpu(size_t size, size_t align) __alloc_size(1); > extern bool __is_kernel_percpu_address(unsigned long addr, unsigned long *can_addr); > extern bool is_kernel_percpu_address(unsigned long addr); > > @@ -131,8 +131,8 @@ extern bool is_kernel_percpu_address(unsigned long addr); > extern void __init setup_per_cpu_areas(void); > #endif > > -extern void __percpu *__alloc_percpu_gfp(size_t size, size_t align, gfp_t gfp); > -extern void __percpu *__alloc_percpu(size_t size, size_t align); > +extern void __percpu *__alloc_percpu_gfp(size_t size, size_t align, gfp_t gfp) __alloc_size(1); > +extern void __percpu *__alloc_percpu(size_t size, size_t align) __alloc_size(1); > extern void free_percpu(void __percpu *__pdata); > extern phys_addr_t per_cpu_ptr_to_phys(void *addr); > > -- > 2.30.2 >
