summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorKefeng Wang <wangkefeng.wang@huawei.com>2021-11-05 21:39:47 +0100
committerLinus Torvalds <torvalds@linux-foundation.org>2021-11-06 21:30:37 +0100
commit3252b1d8309ea42bc6329d9341072ecf1c9505c0 (patch)
treee55752081a97cca77027c9191612c24029ebde1c
parentarm64: support page mapping percpu first chunk allocator (diff)
downloadlinux-3252b1d8309ea42bc6329d9341072ecf1c9505c0.tar.xz
linux-3252b1d8309ea42bc6329d9341072ecf1c9505c0.zip
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.com Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Acked-by: Marco Elver <elver@google.com> [KASAN] Acked-by: Andrey Konovalov <andreyknvl@gmail.com> [KASAN] Acked-by: Catalin 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: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r--arch/arm64/mm/kasan_init.c16
-rw-r--r--include/linux/kasan.h6
-rw-r--r--mm/kasan/shadow.c5
-rw-r--r--mm/vmalloc.c1
4 files changed, 28 insertions, 0 deletions
diff --git a/arch/arm64/mm/kasan_init.c b/arch/arm64/mm/kasan_init.c
index 61b52a92b8b6..5b996ca4d996 100644
--- a/arch/arm64/mm/kasan_init.c
+++ b/arch/arm64/mm/kasan_init.c
@@ -287,6 +287,22 @@ static void __init kasan_init_depth(void)
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)
{
kasan_init_shadow();
diff --git a/include/linux/kasan.h b/include/linux/kasan.h
index 736d7b458996..65487a3b2a71 100644
--- a/include/linux/kasan.h
+++ b/include/linux/kasan.h
@@ -436,6 +436,8 @@ void kasan_release_vmalloc(unsigned long start, unsigned long end,
unsigned long free_region_start,
unsigned long free_region_end);
+void kasan_populate_early_vm_area_shadow(void *start, unsigned long size);
+
#else /* CONFIG_KASAN_VMALLOC */
static inline int kasan_populate_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_end) {}
+static inline void kasan_populate_early_vm_area_shadow(void *start,
+ unsigned long size)
+{ }
+
#endif /* CONFIG_KASAN_VMALLOC */
#if (defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)) && \
diff --git a/mm/kasan/shadow.c b/mm/kasan/shadow.c
index 8d95ee52d019..4a4929b29a23 100644
--- a/mm/kasan/shadow.c
+++ b/mm/kasan/shadow.c
@@ -254,6 +254,11 @@ core_initcall(kasan_memhotplug_init);
#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,
void *unused)
{
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 74da45a8beec..75fa100f5424 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -2291,6 +2291,7 @@ void __init vm_area_register_early(struct vm_struct *vm, size_t align)
vm->addr = (void *)addr;
vm->next = *p;
*p = vm;
+ kasan_populate_early_vm_area_shadow(vm->addr, vm->size);
}
static void vmap_init_free_space(void)