Use vmalloc_array and vcalloc to protect against multiplication overflows. The changes were done using the following Coccinelle semantic patch: // <smpl> @initialize:ocaml@ @@ let rename alloc = match alloc with "vmalloc" -> "vmalloc_array" | "vzalloc" -> "vcalloc" | _ -> failwith "unknown" @@ size_t e1,e2; constant C1, C2; expression E1, E2, COUNT, x1, x2, x3; typedef u8; typedef __u8; type t = {u8,__u8,char,unsigned char}; identifier alloc = {vmalloc,vzalloc}; fresh identifier realloc = script:ocaml(alloc) { rename alloc }; @@ ( alloc(x1*x2*x3) | alloc(C1 * C2) | alloc((sizeof(t)) * (COUNT), ...) | - alloc((e1) * (e2)) + realloc(e1, e2) | - alloc((e1) * (COUNT)) + realloc(COUNT, e1) | - alloc((E1) * (E2)) + realloc(E1, E2) ) // </smpl> Signed-off-by: Julia Lawall <Julia.Lawall@xxxxxxxx> --- v2: Use vmalloc_array and vcalloc instead of array_size. This also leaves a multiplication of a constant by a sizeof as is. Two patches are thus dropped from the series. lib/test_vmalloc.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff -u -p a/lib/test_vmalloc.c b/lib/test_vmalloc.c --- a/lib/test_vmalloc.c +++ b/lib/test_vmalloc.c @@ -156,7 +156,7 @@ static int random_size_alloc_test(void) for (i = 0; i < test_loop_count; i++) { n = get_random_u32_inclusive(1, 100); - p = vmalloc(n * PAGE_SIZE); + p = vmalloc_array(n, PAGE_SIZE); if (!p) return -1; @@ -221,11 +221,11 @@ static int full_fit_alloc_test(void) junk_length = fls(num_online_cpus()); junk_length *= (32 * 1024 * 1024 / PAGE_SIZE); - ptr = vmalloc(sizeof(void *) * junk_length); + ptr = vmalloc_array(junk_length, sizeof(void *)); if (!ptr) return rv; - junk_ptr = vmalloc(sizeof(void *) * junk_length); + junk_ptr = vmalloc_array(junk_length, sizeof(void *)); if (!junk_ptr) { vfree(ptr); return rv; @@ -271,7 +271,8 @@ static int fix_size_alloc_test(void) if (use_huge) ptr = vmalloc_huge((nr_pages > 0 ? nr_pages:1) * PAGE_SIZE, GFP_KERNEL); else - ptr = vmalloc((nr_pages > 0 ? nr_pages:1) * PAGE_SIZE); + ptr = vmalloc_array(nr_pages > 0 ? nr_pages : 1, + PAGE_SIZE); if (!ptr) return -1;