Commit 35fb9ae4 authored by Matthew Wilcox (Oracle)'s avatar Matthew Wilcox (Oracle) Committed by Kees Cook
Browse files

usercopy: Cast pointer to an integer once 



Get rid of a lot of annoying casts by setting 'addr' once at the top
of the function.

Signed-off-by: default avatarMatthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: default avatarUladzislau Rezki (Sony) <urezki@gmail.com>
Tested-by: default avatarZorro Lang <zlang@redhat.com>
Signed-off-by: default avatarKees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20220612213227.3881769-3-willy@infradead.org
parent 993d0b28

mm/usercopy.c

+6 −5
Original line number Diff line number Diff line
@@ -161,26 +161,27 @@ static inline void check_bogus_address(const unsigned long ptr, unsigned long n, 
static inline void check_heap_object(const void *ptr, unsigned long n,

				     bool to_user)

{

	uintptr_t addr = (uintptr_t)ptr;

	struct folio *folio;



	if (is_kmap_addr(ptr)) {

		unsigned long page_end = (unsigned long)ptr | (PAGE_SIZE - 1);

		unsigned long page_end = addr | (PAGE_SIZE - 1);



		if ((unsigned long)ptr + n - 1 > page_end)

		if (addr + n - 1 > page_end)

			usercopy_abort("kmap", NULL, to_user,

					offset_in_page(ptr), n);

		return;

	}



	if (is_vmalloc_addr(ptr)) {

		struct vmap_area *area = find_vmap_area((unsigned long)ptr);

		struct vmap_area *area = find_vmap_area(addr);

		unsigned long offset;



		if (!area)

			usercopy_abort("vmalloc", "no area", to_user, 0, n);



		offset = (unsigned long)ptr - area->va_start;

		if ((unsigned long)ptr + n > area->va_end)

		offset = addr - area->va_start;

		if (addr + n > area->va_end)

			usercopy_abort("vmalloc", NULL, to_user, offset, n);

		return;

	}