From: Kees Cook <keescook@xxxxxxxxxxxx> Subject: percpu: add __alloc_size attributes for better bounds checking 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. Link: https://lkml.kernel.org/r/20210818214021.2476230-7-keescook@xxxxxxxxxxxx Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx> Co-developed-by: Daniel Micay <danielmicay@xxxxxxxxx> Signed-off-by: Daniel Micay <danielmicay@xxxxxxxxx> 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> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/linux/percpu.h | 3 +++ 1 file changed, 3 insertions(+) --- a/include/linux/percpu.h~percpu-add-__alloc_size-attributes-for-better-bounds-checking +++ a/include/linux/percpu.h @@ -123,6 +123,7 @@ extern int __init pcpu_page_first_chunk( pcpu_fc_populate_pte_fn_t populate_pte_fn); #endif +__alloc_size(1) extern void __percpu *__alloc_reserved_percpu(size_t size, size_t align); extern bool __is_kernel_percpu_address(unsigned long addr, unsigned long *can_addr); extern bool is_kernel_percpu_address(unsigned long addr); @@ -131,7 +132,9 @@ extern bool is_kernel_percpu_address(uns extern void __init setup_per_cpu_areas(void); #endif +__alloc_size(1) 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); extern void free_percpu(void __percpu *__pdata); extern phys_addr_t per_cpu_ptr_to_phys(void *addr); _
