Commit 3252b1d8 authored by Kefeng Wang's avatar Kefeng Wang Committed by Linus Torvalds

kasan: arm64: fix pcpu_page_first_chunk crash with KASAN_VMALLOC

With KASAN_VMALLOC and NEED_PER_CPU_PAGE_FIRST_CHUNK the kernel crashes:

  Unable to handle kernel paging request at virtual address ffff7000028f2000
  ...
  swapper pgtable: 64k pages, 48-bit VAs, pgdp=0000000042440000
  [ffff7000028f2000] pgd=000000063e7c0003, p4d=000000063e7c0003, pud=000000063e7c0003, pmd=000000063e7b0003, pte=0000000000000000
  Internal error: Oops: 96000007 [#1] PREEMPT SMP
  Modules linked in:
  CPU: 0 PID: 0 Comm: swapper Not tainted 5.13.0-rc4-00003-gc6e6e28f3f30-dirty #62
  Hardware name: linux,dummy-virt (DT)
  pstate: 200000c5 (nzCv daIF -PAN -UAO -TCO BTYPE=--)
  pc : kasan_check_range+0x90/0x1a0
  lr : memcpy+0x88/0xf4
  sp : ffff80001378fe20
  ...
  Call trace:
   kasan_check_range+0x90/0x1a0
   pcpu_page_first_chunk+0x3f0/0x568
   setup_per_cpu_areas+0xb8/0x184
   start_kernel+0x8c/0x328

The vm area used in vm_area_register_early() has no kasan shadow memory,
Let's add a new kasan_populate_early_vm_area_shadow() function to
populate the vm area shadow memory to fix the issue.

[wangkefeng.wang@huawei.com: fix redefinition of 'kasan_populate_early_vm_area_shadow']
  Link: https://lkml.kernel.org/r/20211011123211.3936196-1-wangkefeng.wang@huawei.com

Link: https://lkml.kernel.org/r/20210910053354.26721-4-wangkefeng.wang@huawei.comSigned-off-by: default avatarKefeng Wang <wangkefeng.wang@huawei.com>
Acked-by: Marco Elver <elver@google.com>		[KASAN]
Acked-by: Andrey Konovalov <andreyknvl@gmail.com>	[KASAN]
Acked-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 09cea619
...@@ -287,6 +287,22 @@ static void __init kasan_init_depth(void) ...@@ -287,6 +287,22 @@ static void __init kasan_init_depth(void)
init_task.kasan_depth = 0; init_task.kasan_depth = 0;
} }
#ifdef CONFIG_KASAN_VMALLOC
void __init kasan_populate_early_vm_area_shadow(void *start, unsigned long size)
{
unsigned long shadow_start, shadow_end;
if (!is_vmalloc_or_module_addr(start))
return;
shadow_start = (unsigned long)kasan_mem_to_shadow(start);
shadow_start = ALIGN_DOWN(shadow_start, PAGE_SIZE);
shadow_end = (unsigned long)kasan_mem_to_shadow(start + size);
shadow_end = ALIGN(shadow_end, PAGE_SIZE);
kasan_map_populate(shadow_start, shadow_end, NUMA_NO_NODE);
}
#endif
void __init kasan_init(void) void __init kasan_init(void)
{ {
kasan_init_shadow(); kasan_init_shadow();
......
...@@ -436,6 +436,8 @@ void kasan_release_vmalloc(unsigned long start, unsigned long end, ...@@ -436,6 +436,8 @@ void kasan_release_vmalloc(unsigned long start, unsigned long end,
unsigned long free_region_start, unsigned long free_region_start,
unsigned long free_region_end); unsigned long free_region_end);
void kasan_populate_early_vm_area_shadow(void *start, unsigned long size);
#else /* CONFIG_KASAN_VMALLOC */ #else /* CONFIG_KASAN_VMALLOC */
static inline int kasan_populate_vmalloc(unsigned long start, static inline int kasan_populate_vmalloc(unsigned long start,
...@@ -453,6 +455,10 @@ static inline void kasan_release_vmalloc(unsigned long start, ...@@ -453,6 +455,10 @@ static inline void kasan_release_vmalloc(unsigned long start,
unsigned long free_region_start, unsigned long free_region_start,
unsigned long free_region_end) {} unsigned long free_region_end) {}
static inline void kasan_populate_early_vm_area_shadow(void *start,
unsigned long size)
{ }
#endif /* CONFIG_KASAN_VMALLOC */ #endif /* CONFIG_KASAN_VMALLOC */
#if (defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)) && \ #if (defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)) && \
......
...@@ -254,6 +254,11 @@ core_initcall(kasan_memhotplug_init); ...@@ -254,6 +254,11 @@ core_initcall(kasan_memhotplug_init);
#ifdef CONFIG_KASAN_VMALLOC #ifdef CONFIG_KASAN_VMALLOC
void __init __weak kasan_populate_early_vm_area_shadow(void *start,
unsigned long size)
{
}
static int kasan_populate_vmalloc_pte(pte_t *ptep, unsigned long addr, static int kasan_populate_vmalloc_pte(pte_t *ptep, unsigned long addr,
void *unused) void *unused)
{ {
......
...@@ -2291,6 +2291,7 @@ void __init vm_area_register_early(struct vm_struct *vm, size_t align) ...@@ -2291,6 +2291,7 @@ void __init vm_area_register_early(struct vm_struct *vm, size_t align)
vm->addr = (void *)addr; vm->addr = (void *)addr;
vm->next = *p; vm->next = *p;
*p = vm; *p = vm;
kasan_populate_early_vm_area_shadow(vm->addr, vm->size);
} }
static void vmap_init_free_space(void) static void vmap_init_free_space(void)
......
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