From: Sean Christopherson <seanjc@google.com> mainline inclusion from mainline-v6.2-rc1 commit bde258d97409f2a45243cb393a55ea9ecfc7aba5 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I6C6UC CVE: CVE-2023-0597 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... -------------------------------- Add helpers to dedup code for aligning shadow address up/down to page boundaries when translating an address to its shadow. No functional change intended. Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Andrey Ryabinin <ryabinin.a.a@gmail.com> Link: https://lkml.kernel.org/r/20221110203504.1985010-5-seanjc@google.com Signed-off-by: Tong Tiangen <tongtiangen@huawei.com> Reviewed-by: Wang Weiyang <wangweiyang2@huawei.com> Reviewed-by: Kefeng Wang <wangkefeng.wang@huawei.com> Signed-off-by: Jialin Zhang <zhangjialin11@huawei.com> --- arch/x86/mm/kasan_init_64.c | 40 ++++++++++++++++++++----------------- 1 file changed, 22 insertions(+), 18 deletions(-) diff --git a/arch/x86/mm/kasan_init_64.c b/arch/x86/mm/kasan_init_64.c index 75b0eb482487..c1d99556c024 100644 --- a/arch/x86/mm/kasan_init_64.c +++ b/arch/x86/mm/kasan_init_64.c @@ -318,22 +318,33 @@ void __init kasan_early_init(void) kasan_map_early_shadow(init_top_pgt); } +static unsigned long kasan_mem_to_shadow_align_down(unsigned long va) +{ + unsigned long shadow = (unsigned long)kasan_mem_to_shadow((void *)va); + + return round_down(shadow, PAGE_SIZE); +} + +static unsigned long kasan_mem_to_shadow_align_up(unsigned long va) +{ + unsigned long shadow = (unsigned long)kasan_mem_to_shadow((void *)va); + + return round_up(shadow, PAGE_SIZE); +} + void __init kasan_populate_shadow_for_vaddr(void *va, size_t size, int nid) { unsigned long shadow_start, shadow_end; - shadow_start = (unsigned long)kasan_mem_to_shadow(va); - shadow_start = round_down(shadow_start, PAGE_SIZE); - shadow_end = (unsigned long)kasan_mem_to_shadow(va + size); - shadow_end = round_up(shadow_end, PAGE_SIZE); - + shadow_start = kasan_mem_to_shadow_align_down((unsigned long)va); + shadow_end = kasan_mem_to_shadow_align_up((unsigned long)va + size); kasan_populate_shadow(shadow_start, shadow_end, nid); } void __init kasan_init(void) { + unsigned long shadow_cea_begin, shadow_cea_end; int i; - void *shadow_cea_begin, *shadow_cea_end; memcpy(early_top_pgt, init_top_pgt, sizeof(early_top_pgt)); @@ -374,16 +385,9 @@ void __init kasan_init(void) map_range(&pfn_mapped[i]); } - shadow_cea_begin = (void *)CPU_ENTRY_AREA_BASE; - shadow_cea_begin = kasan_mem_to_shadow(shadow_cea_begin); - shadow_cea_begin = (void *)round_down( - (unsigned long)shadow_cea_begin, PAGE_SIZE); - - shadow_cea_end = (void *)(CPU_ENTRY_AREA_BASE + - CPU_ENTRY_AREA_MAP_SIZE); - shadow_cea_end = kasan_mem_to_shadow(shadow_cea_end); - shadow_cea_end = (void *)round_up( - (unsigned long)shadow_cea_end, PAGE_SIZE); + shadow_cea_begin = kasan_mem_to_shadow_align_down(CPU_ENTRY_AREA_BASE); + shadow_cea_end = kasan_mem_to_shadow_align_up(CPU_ENTRY_AREA_BASE + + CPU_ENTRY_AREA_MAP_SIZE); kasan_populate_early_shadow( kasan_mem_to_shadow((void *)PAGE_OFFSET + MAXMEM), @@ -405,9 +409,9 @@ void __init kasan_init(void) kasan_populate_early_shadow( kasan_mem_to_shadow((void *)VMALLOC_END + 1), - shadow_cea_begin); + (void *)shadow_cea_begin); - kasan_populate_early_shadow(shadow_cea_end, + kasan_populate_early_shadow((void *)shadow_cea_end, kasan_mem_to_shadow((void *)__START_KERNEL_map)); kasan_populate_shadow((unsigned long)kasan_mem_to_shadow(_stext), -- 2.25.1