| Message ID | 20230627144339.144478-7-Julia.Lawall@inria.fr (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | use vmalloc_array and vcalloc | expand |
On Tue, Jun 27, 2023 at 7:44 AM Julia Lawall <Julia.Lawall@inria.fr> wrote: > > 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@inria.fr> > > --- > 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. > > drivers/dma-buf/heaps/system_heap.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff -u -p a/drivers/dma-buf/heaps/system_heap.c b/drivers/dma-buf/heaps/system_heap.c > --- a/drivers/dma-buf/heaps/system_heap.c > +++ b/drivers/dma-buf/heaps/system_heap.c > @@ -221,7 +221,7 @@ static void *system_heap_do_vmap(struct > { > struct sg_table *table = &buffer->sg_table; > int npages = PAGE_ALIGN(buffer->len) / PAGE_SIZE; > - struct page **pages = vmalloc(sizeof(struct page *) * npages); > + struct page **pages = vmalloc_array(npages, sizeof(struct page *)); > struct page **tmp = pages; > struct sg_page_iter piter; > void *vaddr; Seems reasonable. Thanks for sending this out! Acked-by: John Stultz <jstultz@google.com> thanks -john
diff -u -p a/drivers/dma-buf/heaps/system_heap.c b/drivers/dma-buf/heaps/system_heap.c --- a/drivers/dma-buf/heaps/system_heap.c +++ b/drivers/dma-buf/heaps/system_heap.c @@ -221,7 +221,7 @@ static void *system_heap_do_vmap(struct { struct sg_table *table = &buffer->sg_table; int npages = PAGE_ALIGN(buffer->len) / PAGE_SIZE; - struct page **pages = vmalloc(sizeof(struct page *) * npages); + struct page **pages = vmalloc_array(npages, sizeof(struct page *)); struct page **tmp = pages; struct sg_page_iter piter; void *vaddr;
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@inria.fr> --- 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. drivers/dma-buf/heaps/system_heap.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)