diff options
Diffstat (limited to 'include')
-rw-r--r-- | include/linux/highmem.h | 3 | ||||
-rw-r--r-- | include/linux/kmsan.h | 145 |
2 files changed, 148 insertions, 0 deletions
diff --git a/include/linux/highmem.h b/include/linux/highmem.h index 25679035ca28..e9912da5441b 100644 --- a/include/linux/highmem.h +++ b/include/linux/highmem.h @@ -6,6 +6,7 @@ #include <linux/kernel.h> #include <linux/bug.h> #include <linux/cacheflush.h> +#include <linux/kmsan.h> #include <linux/mm.h> #include <linux/uaccess.h> #include <linux/hardirq.h> @@ -311,6 +312,7 @@ static inline void copy_user_highpage(struct page *to, struct page *from, vfrom = kmap_local_page(from); vto = kmap_local_page(to); copy_user_page(vto, vfrom, vaddr, to); + kmsan_unpoison_memory(page_address(to), PAGE_SIZE); kunmap_local(vto); kunmap_local(vfrom); } @@ -326,6 +328,7 @@ static inline void copy_highpage(struct page *to, struct page *from) vfrom = kmap_local_page(from); vto = kmap_local_page(to); copy_page(vto, vfrom); + kmsan_copy_page_meta(to, from); kunmap_local(vto); kunmap_local(vfrom); } diff --git a/include/linux/kmsan.h b/include/linux/kmsan.h new file mode 100644 index 000000000000..b36bf3db835e --- /dev/null +++ b/include/linux/kmsan.h @@ -0,0 +1,145 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * KMSAN API for subsystems. + * + * Copyright (C) 2017-2022 Google LLC + * Author: Alexander Potapenko <glider@google.com> + * + */ +#ifndef _LINUX_KMSAN_H +#define _LINUX_KMSAN_H + +#include <linux/gfp.h> +#include <linux/kmsan-checks.h> +#include <linux/types.h> + +struct page; + +#ifdef CONFIG_KMSAN + +/** + * kmsan_alloc_page() - Notify KMSAN about an alloc_pages() call. + * @page: struct page pointer returned by alloc_pages(). + * @order: order of allocated struct page. + * @flags: GFP flags used by alloc_pages() + * + * KMSAN marks 1<<@order pages starting at @page as uninitialized, unless + * @flags contain __GFP_ZERO. + */ +void kmsan_alloc_page(struct page *page, unsigned int order, gfp_t flags); + +/** + * kmsan_free_page() - Notify KMSAN about a free_pages() call. + * @page: struct page pointer passed to free_pages(). + * @order: order of deallocated struct page. + * + * KMSAN marks freed memory as uninitialized. + */ +void kmsan_free_page(struct page *page, unsigned int order); + +/** + * kmsan_copy_page_meta() - Copy KMSAN metadata between two pages. + * @dst: destination page. + * @src: source page. + * + * KMSAN copies the contents of metadata pages for @src into the metadata pages + * for @dst. If @dst has no associated metadata pages, nothing happens. + * If @src has no associated metadata pages, @dst metadata pages are unpoisoned. + */ +void kmsan_copy_page_meta(struct page *dst, struct page *src); + +/** + * kmsan_map_kernel_range_noflush() - Notify KMSAN about a vmap. + * @start: start of vmapped range. + * @end: end of vmapped range. + * @prot: page protection flags used for vmap. + * @pages: array of pages. + * @page_shift: page_shift passed to vmap_range_noflush(). + * + * KMSAN maps shadow and origin pages of @pages into contiguous ranges in + * vmalloc metadata address range. + */ +void kmsan_vmap_pages_range_noflush(unsigned long start, unsigned long end, + pgprot_t prot, struct page **pages, + unsigned int page_shift); + +/** + * kmsan_vunmap_kernel_range_noflush() - Notify KMSAN about a vunmap. + * @start: start of vunmapped range. + * @end: end of vunmapped range. + * + * KMSAN unmaps the contiguous metadata ranges created by + * kmsan_map_kernel_range_noflush(). + */ +void kmsan_vunmap_range_noflush(unsigned long start, unsigned long end); + +/** + * kmsan_ioremap_page_range() - Notify KMSAN about a ioremap_page_range() call. + * @addr: range start. + * @end: range end. + * @phys_addr: physical range start. + * @prot: page protection flags used for ioremap_page_range(). + * @page_shift: page_shift argument passed to vmap_range_noflush(). + * + * KMSAN creates new metadata pages for the physical pages mapped into the + * virtual memory. + */ +void kmsan_ioremap_page_range(unsigned long addr, unsigned long end, + phys_addr_t phys_addr, pgprot_t prot, + unsigned int page_shift); + +/** + * kmsan_iounmap_page_range() - Notify KMSAN about a iounmap_page_range() call. + * @start: range start. + * @end: range end. + * + * KMSAN unmaps the metadata pages for the given range and, unlike for + * vunmap_page_range(), also deallocates them. + */ +void kmsan_iounmap_page_range(unsigned long start, unsigned long end); + +#else + +static inline int kmsan_alloc_page(struct page *page, unsigned int order, + gfp_t flags) +{ + return 0; +} + +static inline void kmsan_free_page(struct page *page, unsigned int order) +{ +} + +static inline void kmsan_copy_page_meta(struct page *dst, struct page *src) +{ +} + +static inline void kmsan_vmap_pages_range_noflush(unsigned long start, + unsigned long end, + pgprot_t prot, + struct page **pages, + unsigned int page_shift) +{ +} + +static inline void kmsan_vunmap_range_noflush(unsigned long start, + unsigned long end) +{ +} + +static inline void kmsan_ioremap_page_range(unsigned long start, + unsigned long end, + phys_addr_t phys_addr, + pgprot_t prot, + unsigned int page_shift) +{ +} + +static inline void kmsan_iounmap_page_range(unsigned long start, + unsigned long end) +{ +} + +#endif + +#endif /* _LINUX_KMSAN_H */ |