Update Linux to v5.10.109
Sourced from [1]
[1] https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.10.109.tar.xz
Change-Id: I19bca9fc6762d4e63bcf3e4cba88bbe560d9c76c
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/mm/kasan/Makefile b/mm/kasan/Makefile
index f36ffc0..370d970 100644
--- a/mm/kasan/Makefile
+++ b/mm/kasan/Makefile
@@ -1,23 +1,33 @@
# SPDX-License-Identifier: GPL-2.0
KASAN_SANITIZE := n
-UBSAN_SANITIZE_common.o := n
-UBSAN_SANITIZE_generic.o := n
-UBSAN_SANITIZE_generic_report.o := n
-UBSAN_SANITIZE_tags.o := n
+UBSAN_SANITIZE := n
KCOV_INSTRUMENT := n
+# Disable ftrace to avoid recursion.
CFLAGS_REMOVE_common.o = $(CC_FLAGS_FTRACE)
CFLAGS_REMOVE_generic.o = $(CC_FLAGS_FTRACE)
CFLAGS_REMOVE_generic_report.o = $(CC_FLAGS_FTRACE)
+CFLAGS_REMOVE_init.o = $(CC_FLAGS_FTRACE)
+CFLAGS_REMOVE_quarantine.o = $(CC_FLAGS_FTRACE)
+CFLAGS_REMOVE_report.o = $(CC_FLAGS_FTRACE)
CFLAGS_REMOVE_tags.o = $(CC_FLAGS_FTRACE)
+CFLAGS_REMOVE_tags_report.o = $(CC_FLAGS_FTRACE)
# Function splitter causes unnecessary splits in __asan_load1/__asan_store1
# see: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63533
+CC_FLAGS_KASAN_RUNTIME := $(call cc-option, -fno-conserve-stack)
+CC_FLAGS_KASAN_RUNTIME += -fno-stack-protector
+# Disable branch tracing to avoid recursion.
+CC_FLAGS_KASAN_RUNTIME += -DDISABLE_BRANCH_PROFILING
-CFLAGS_common.o := $(call cc-option, -fno-conserve-stack -fno-stack-protector) -DDISABLE_BRANCH_PROFILING
-CFLAGS_generic.o := $(call cc-option, -fno-conserve-stack -fno-stack-protector) -DDISABLE_BRANCH_PROFILING
-CFLAGS_generic_report.o := $(call cc-option, -fno-conserve-stack -fno-stack-protector) -DDISABLE_BRANCH_PROFILING
-CFLAGS_tags.o := $(call cc-option, -fno-conserve-stack -fno-stack-protector) -DDISABLE_BRANCH_PROFILING
+CFLAGS_common.o := $(CC_FLAGS_KASAN_RUNTIME)
+CFLAGS_generic.o := $(CC_FLAGS_KASAN_RUNTIME)
+CFLAGS_generic_report.o := $(CC_FLAGS_KASAN_RUNTIME)
+CFLAGS_init.o := $(CC_FLAGS_KASAN_RUNTIME)
+CFLAGS_quarantine.o := $(CC_FLAGS_KASAN_RUNTIME)
+CFLAGS_report.o := $(CC_FLAGS_KASAN_RUNTIME)
+CFLAGS_tags.o := $(CC_FLAGS_KASAN_RUNTIME)
+CFLAGS_tags_report.o := $(CC_FLAGS_KASAN_RUNTIME)
obj-$(CONFIG_KASAN) := common.o init.o report.o
obj-$(CONFIG_KASAN_GENERIC) += generic.o generic_report.o quarantine.o
diff --git a/mm/kasan/common.c b/mm/kasan/common.c
index 6814d6d..950fd37 100644
--- a/mm/kasan/common.c
+++ b/mm/kasan/common.c
@@ -15,7 +15,6 @@
*/
#include <linux/export.h>
-#include <linux/interrupt.h>
#include <linux/init.h>
#include <linux/kasan.h>
#include <linux/kernel.h>
@@ -34,34 +33,14 @@
#include <linux/types.h>
#include <linux/vmalloc.h>
#include <linux/bug.h>
-#include <linux/uaccess.h>
+
+#include <asm/cacheflush.h>
+#include <asm/tlbflush.h>
#include "kasan.h"
#include "../slab.h"
-static inline int in_irqentry_text(unsigned long ptr)
-{
- return (ptr >= (unsigned long)&__irqentry_text_start &&
- ptr < (unsigned long)&__irqentry_text_end) ||
- (ptr >= (unsigned long)&__softirqentry_text_start &&
- ptr < (unsigned long)&__softirqentry_text_end);
-}
-
-static inline unsigned int filter_irq_stacks(unsigned long *entries,
- unsigned int nr_entries)
-{
- unsigned int i;
-
- for (i = 0; i < nr_entries; i++) {
- if (in_irqentry_text(entries[i])) {
- /* Include the irqentry function into the stack. */
- return i + 1;
- }
- }
- return nr_entries;
-}
-
-static inline depot_stack_handle_t save_stack(gfp_t flags)
+depot_stack_handle_t kasan_save_stack(gfp_t flags)
{
unsigned long entries[KASAN_STACK_DEPTH];
unsigned int nr_entries;
@@ -71,10 +50,10 @@
return stack_depot_save(entries, nr_entries, flags);
}
-static inline void set_track(struct kasan_track *track, gfp_t flags)
+void kasan_set_track(struct kasan_track *track, gfp_t flags)
{
track->pid = current->pid;
- track->stack = save_stack(flags);
+ track->stack = kasan_save_stack(flags);
}
void kasan_enable_current(void)
@@ -102,25 +81,30 @@
#undef memset
void *memset(void *addr, int c, size_t len)
{
- check_memory_region((unsigned long)addr, len, true, _RET_IP_);
+ if (!check_memory_region((unsigned long)addr, len, true, _RET_IP_))
+ return NULL;
return __memset(addr, c, len);
}
+#ifdef __HAVE_ARCH_MEMMOVE
#undef memmove
void *memmove(void *dest, const void *src, size_t len)
{
- check_memory_region((unsigned long)src, len, false, _RET_IP_);
- check_memory_region((unsigned long)dest, len, true, _RET_IP_);
+ if (!check_memory_region((unsigned long)src, len, false, _RET_IP_) ||
+ !check_memory_region((unsigned long)dest, len, true, _RET_IP_))
+ return NULL;
return __memmove(dest, src, len);
}
+#endif
#undef memcpy
void *memcpy(void *dest, const void *src, size_t len)
{
- check_memory_region((unsigned long)src, len, false, _RET_IP_);
- check_memory_region((unsigned long)dest, len, true, _RET_IP_);
+ if (!check_memory_region((unsigned long)src, len, false, _RET_IP_) ||
+ !check_memory_region((unsigned long)dest, len, true, _RET_IP_))
+ return NULL;
return __memcpy(dest, src, len);
}
@@ -196,21 +180,6 @@
kasan_unpoison_shadow(base, watermark - base);
}
-/*
- * Clear all poison for the region between the current SP and a provided
- * watermark value, as is sometimes required prior to hand-crafted asm function
- * returns in the middle of functions.
- */
-void kasan_unpoison_stack_above_sp_to(const void *watermark)
-{
- const void *sp = __builtin_frame_address(0);
- size_t size = watermark - sp;
-
- if (WARN_ON(sp > watermark))
- return;
- kasan_unpoison_shadow(sp, size);
-}
-
void kasan_alloc_pages(struct page *page, unsigned int order)
{
u8 tag;
@@ -314,24 +283,6 @@
return (void *)object + cache->kasan_info.free_meta_offset;
}
-
-static void kasan_set_free_info(struct kmem_cache *cache,
- void *object, u8 tag)
-{
- struct kasan_alloc_meta *alloc_meta;
- u8 idx = 0;
-
- alloc_meta = get_alloc_info(cache, object);
-
-#ifdef CONFIG_KASAN_SW_TAGS_IDENTIFY
- idx = alloc_meta->free_track_idx;
- alloc_meta->free_pointer_tag[idx] = tag;
- alloc_meta->free_track_idx = (idx + 1) % KASAN_NR_FREE_STACKS;
-#endif
-
- set_track(&alloc_meta->free_track[idx], GFP_NOWAIT);
-}
-
void kasan_poison_slab(struct page *page)
{
unsigned long i;
@@ -507,7 +458,7 @@
KASAN_KMALLOC_REDZONE);
if (cache->flags & SLAB_KASAN)
- set_track(&get_alloc_info(cache, object)->alloc_track, flags);
+ kasan_set_track(&get_alloc_info(cache, object)->alloc_track, flags);
return set_tag(object, tag);
}
@@ -590,6 +541,7 @@
/* The object will be poisoned by page_alloc. */
}
+#ifndef CONFIG_KASAN_VMALLOC
int kasan_module_alloc(void *addr, size_t size)
{
void *ret;
@@ -625,15 +577,7 @@
if (vm->flags & VM_KASAN)
vfree(kasan_mem_to_shadow(vm->addr));
}
-
-extern void __kasan_report(unsigned long addr, size_t size, bool is_write, unsigned long ip);
-
-void kasan_report(unsigned long addr, size_t size, bool is_write, unsigned long ip)
-{
- unsigned long flags = user_access_save();
- __kasan_report(addr, size, is_write, ip);
- user_access_restore(flags);
-}
+#endif
#ifdef CONFIG_MEMORY_HOTPLUG
static bool shadow_mapped(unsigned long addr)
@@ -744,3 +688,244 @@
core_initcall(kasan_memhotplug_init);
#endif
+
+#ifdef CONFIG_KASAN_VMALLOC
+static int kasan_populate_vmalloc_pte(pte_t *ptep, unsigned long addr,
+ void *unused)
+{
+ unsigned long page;
+ pte_t pte;
+
+ if (likely(!pte_none(*ptep)))
+ return 0;
+
+ page = __get_free_page(GFP_KERNEL);
+ if (!page)
+ return -ENOMEM;
+
+ memset((void *)page, KASAN_VMALLOC_INVALID, PAGE_SIZE);
+ pte = pfn_pte(PFN_DOWN(__pa(page)), PAGE_KERNEL);
+
+ spin_lock(&init_mm.page_table_lock);
+ if (likely(pte_none(*ptep))) {
+ set_pte_at(&init_mm, addr, ptep, pte);
+ page = 0;
+ }
+ spin_unlock(&init_mm.page_table_lock);
+ if (page)
+ free_page(page);
+ return 0;
+}
+
+int kasan_populate_vmalloc(unsigned long addr, unsigned long size)
+{
+ unsigned long shadow_start, shadow_end;
+ int ret;
+
+ if (!is_vmalloc_or_module_addr((void *)addr))
+ return 0;
+
+ shadow_start = (unsigned long)kasan_mem_to_shadow((void *)addr);
+ shadow_start = ALIGN_DOWN(shadow_start, PAGE_SIZE);
+ shadow_end = (unsigned long)kasan_mem_to_shadow((void *)addr + size);
+ shadow_end = ALIGN(shadow_end, PAGE_SIZE);
+
+ ret = apply_to_page_range(&init_mm, shadow_start,
+ shadow_end - shadow_start,
+ kasan_populate_vmalloc_pte, NULL);
+ if (ret)
+ return ret;
+
+ flush_cache_vmap(shadow_start, shadow_end);
+
+ /*
+ * We need to be careful about inter-cpu effects here. Consider:
+ *
+ * CPU#0 CPU#1
+ * WRITE_ONCE(p, vmalloc(100)); while (x = READ_ONCE(p)) ;
+ * p[99] = 1;
+ *
+ * With compiler instrumentation, that ends up looking like this:
+ *
+ * CPU#0 CPU#1
+ * // vmalloc() allocates memory
+ * // let a = area->addr
+ * // we reach kasan_populate_vmalloc
+ * // and call kasan_unpoison_shadow:
+ * STORE shadow(a), unpoison_val
+ * ...
+ * STORE shadow(a+99), unpoison_val x = LOAD p
+ * // rest of vmalloc process <data dependency>
+ * STORE p, a LOAD shadow(x+99)
+ *
+ * If there is no barrier between the end of unpoisioning the shadow
+ * and the store of the result to p, the stores could be committed
+ * in a different order by CPU#0, and CPU#1 could erroneously observe
+ * poison in the shadow.
+ *
+ * We need some sort of barrier between the stores.
+ *
+ * In the vmalloc() case, this is provided by a smp_wmb() in
+ * clear_vm_uninitialized_flag(). In the per-cpu allocator and in
+ * get_vm_area() and friends, the caller gets shadow allocated but
+ * doesn't have any pages mapped into the virtual address space that
+ * has been reserved. Mapping those pages in will involve taking and
+ * releasing a page-table lock, which will provide the barrier.
+ */
+
+ return 0;
+}
+
+/*
+ * Poison the shadow for a vmalloc region. Called as part of the
+ * freeing process at the time the region is freed.
+ */
+void kasan_poison_vmalloc(const void *start, unsigned long size)
+{
+ if (!is_vmalloc_or_module_addr(start))
+ return;
+
+ size = round_up(size, KASAN_SHADOW_SCALE_SIZE);
+ kasan_poison_shadow(start, size, KASAN_VMALLOC_INVALID);
+}
+
+void kasan_unpoison_vmalloc(const void *start, unsigned long size)
+{
+ if (!is_vmalloc_or_module_addr(start))
+ return;
+
+ kasan_unpoison_shadow(start, size);
+}
+
+static int kasan_depopulate_vmalloc_pte(pte_t *ptep, unsigned long addr,
+ void *unused)
+{
+ unsigned long page;
+
+ page = (unsigned long)__va(pte_pfn(*ptep) << PAGE_SHIFT);
+
+ spin_lock(&init_mm.page_table_lock);
+
+ if (likely(!pte_none(*ptep))) {
+ pte_clear(&init_mm, addr, ptep);
+ free_page(page);
+ }
+ spin_unlock(&init_mm.page_table_lock);
+
+ return 0;
+}
+
+/*
+ * Release the backing for the vmalloc region [start, end), which
+ * lies within the free region [free_region_start, free_region_end).
+ *
+ * This can be run lazily, long after the region was freed. It runs
+ * under vmap_area_lock, so it's not safe to interact with the vmalloc/vmap
+ * infrastructure.
+ *
+ * How does this work?
+ * -------------------
+ *
+ * We have a region that is page aligned, labelled as A.
+ * That might not map onto the shadow in a way that is page-aligned:
+ *
+ * start end
+ * v v
+ * |????????|????????|AAAAAAAA|AA....AA|AAAAAAAA|????????| < vmalloc
+ * -------- -------- -------- -------- --------
+ * | | | | |
+ * | | | /-------/ |
+ * \-------\|/------/ |/---------------/
+ * ||| ||
+ * |??AAAAAA|AAAAAAAA|AA??????| < shadow
+ * (1) (2) (3)
+ *
+ * First we align the start upwards and the end downwards, so that the
+ * shadow of the region aligns with shadow page boundaries. In the
+ * example, this gives us the shadow page (2). This is the shadow entirely
+ * covered by this allocation.
+ *
+ * Then we have the tricky bits. We want to know if we can free the
+ * partially covered shadow pages - (1) and (3) in the example. For this,
+ * we are given the start and end of the free region that contains this
+ * allocation. Extending our previous example, we could have:
+ *
+ * free_region_start free_region_end
+ * | start end |
+ * v v v v
+ * |FFFFFFFF|FFFFFFFF|AAAAAAAA|AA....AA|AAAAAAAA|FFFFFFFF| < vmalloc
+ * -------- -------- -------- -------- --------
+ * | | | | |
+ * | | | /-------/ |
+ * \-------\|/------/ |/---------------/
+ * ||| ||
+ * |FFAAAAAA|AAAAAAAA|AAF?????| < shadow
+ * (1) (2) (3)
+ *
+ * Once again, we align the start of the free region up, and the end of
+ * the free region down so that the shadow is page aligned. So we can free
+ * page (1) - we know no allocation currently uses anything in that page,
+ * because all of it is in the vmalloc free region. But we cannot free
+ * page (3), because we can't be sure that the rest of it is unused.
+ *
+ * We only consider pages that contain part of the original region for
+ * freeing: we don't try to free other pages from the free region or we'd
+ * end up trying to free huge chunks of virtual address space.
+ *
+ * Concurrency
+ * -----------
+ *
+ * How do we know that we're not freeing a page that is simultaneously
+ * being used for a fresh allocation in kasan_populate_vmalloc(_pte)?
+ *
+ * We _can_ have kasan_release_vmalloc and kasan_populate_vmalloc running
+ * at the same time. While we run under free_vmap_area_lock, the population
+ * code does not.
+ *
+ * free_vmap_area_lock instead operates to ensure that the larger range
+ * [free_region_start, free_region_end) is safe: because __alloc_vmap_area and
+ * the per-cpu region-finding algorithm both run under free_vmap_area_lock,
+ * no space identified as free will become used while we are running. This
+ * means that so long as we are careful with alignment and only free shadow
+ * pages entirely covered by the free region, we will not run in to any
+ * trouble - any simultaneous allocations will be for disjoint regions.
+ */
+void kasan_release_vmalloc(unsigned long start, unsigned long end,
+ unsigned long free_region_start,
+ unsigned long free_region_end)
+{
+ void *shadow_start, *shadow_end;
+ unsigned long region_start, region_end;
+ unsigned long size;
+
+ region_start = ALIGN(start, PAGE_SIZE * KASAN_SHADOW_SCALE_SIZE);
+ region_end = ALIGN_DOWN(end, PAGE_SIZE * KASAN_SHADOW_SCALE_SIZE);
+
+ free_region_start = ALIGN(free_region_start,
+ PAGE_SIZE * KASAN_SHADOW_SCALE_SIZE);
+
+ if (start != region_start &&
+ free_region_start < region_start)
+ region_start -= PAGE_SIZE * KASAN_SHADOW_SCALE_SIZE;
+
+ free_region_end = ALIGN_DOWN(free_region_end,
+ PAGE_SIZE * KASAN_SHADOW_SCALE_SIZE);
+
+ if (end != region_end &&
+ free_region_end > region_end)
+ region_end += PAGE_SIZE * KASAN_SHADOW_SCALE_SIZE;
+
+ shadow_start = kasan_mem_to_shadow((void *)region_start);
+ shadow_end = kasan_mem_to_shadow((void *)region_end);
+
+ if (shadow_end > shadow_start) {
+ size = shadow_end - shadow_start;
+ apply_to_existing_page_range(&init_mm,
+ (unsigned long)shadow_start,
+ size, kasan_depopulate_vmalloc_pte,
+ NULL);
+ flush_tlb_kernel_range((unsigned long)shadow_start,
+ (unsigned long)shadow_end);
+ }
+}
+#endif
diff --git a/mm/kasan/generic.c b/mm/kasan/generic.c
index 76a8003..248264b 100644
--- a/mm/kasan/generic.c
+++ b/mm/kasan/generic.c
@@ -172,17 +172,18 @@
if (unlikely(size == 0))
return true;
+ if (unlikely(addr + size < addr))
+ return !kasan_report(addr, size, write, ret_ip);
+
if (unlikely((void *)addr <
kasan_shadow_to_mem((void *)KASAN_SHADOW_START))) {
- kasan_report(addr, size, write, ret_ip);
- return false;
+ return !kasan_report(addr, size, write, ret_ip);
}
if (likely(!memory_is_poisoned(addr, size)))
return true;
- kasan_report(addr, size, write, ret_ip);
- return false;
+ return !kasan_report(addr, size, write, ret_ip);
}
bool check_memory_region(unsigned long addr, size_t size, bool write,
@@ -323,3 +324,46 @@
DEFINE_ASAN_SET_SHADOW(f3);
DEFINE_ASAN_SET_SHADOW(f5);
DEFINE_ASAN_SET_SHADOW(f8);
+
+void kasan_record_aux_stack(void *addr)
+{
+ struct page *page = kasan_addr_to_page(addr);
+ struct kmem_cache *cache;
+ struct kasan_alloc_meta *alloc_info;
+ void *object;
+
+ if (!(page && PageSlab(page)))
+ return;
+
+ cache = page->slab_cache;
+ object = nearest_obj(cache, page, addr);
+ alloc_info = get_alloc_info(cache, object);
+
+ /*
+ * record the last two call_rcu() call stacks.
+ */
+ alloc_info->aux_stack[1] = alloc_info->aux_stack[0];
+ alloc_info->aux_stack[0] = kasan_save_stack(GFP_NOWAIT);
+}
+
+void kasan_set_free_info(struct kmem_cache *cache,
+ void *object, u8 tag)
+{
+ struct kasan_free_meta *free_meta;
+
+ free_meta = get_free_info(cache, object);
+ kasan_set_track(&free_meta->free_track, GFP_NOWAIT);
+
+ /*
+ * the object was freed and has free track set
+ */
+ *(u8 *)kasan_mem_to_shadow(object) = KASAN_KMALLOC_FREETRACK;
+}
+
+struct kasan_track *kasan_get_free_track(struct kmem_cache *cache,
+ void *object, u8 tag)
+{
+ if (*(u8 *)kasan_mem_to_shadow(object) != KASAN_KMALLOC_FREETRACK)
+ return NULL;
+ return &get_free_info(cache, object)->free_track;
+}
diff --git a/mm/kasan/generic_report.c b/mm/kasan/generic_report.c
index 36c6459..a38c7a9 100644
--- a/mm/kasan/generic_report.c
+++ b/mm/kasan/generic_report.c
@@ -80,12 +80,16 @@
break;
case KASAN_FREE_PAGE:
case KASAN_KMALLOC_FREE:
+ case KASAN_KMALLOC_FREETRACK:
bug_type = "use-after-free";
break;
case KASAN_ALLOCA_LEFT:
case KASAN_ALLOCA_RIGHT:
bug_type = "alloca-out-of-bounds";
break;
+ case KASAN_VMALLOC_INVALID:
+ bug_type = "vmalloc-out-of-bounds";
+ break;
}
return bug_type;
@@ -107,6 +111,17 @@
const char *get_bug_type(struct kasan_access_info *info)
{
+ /*
+ * If access_size is a negative number, then it has reason to be
+ * defined as out-of-bounds bug type.
+ *
+ * Casting negative numbers to size_t would indeed turn up as
+ * a large size_t and its value will be larger than ULONG_MAX/2,
+ * so that this can qualify as out-of-bounds.
+ */
+ if (info->access_addr + info->access_size < info->access_addr)
+ return "out-of-bounds";
+
if (addr_has_shadow(info->access_addr))
return get_shadow_bug_type(info);
return get_wild_bug_type(info);
diff --git a/mm/kasan/init.c b/mm/kasan/init.c
index ee21e1c..b8c6ec1 100644
--- a/mm/kasan/init.c
+++ b/mm/kasan/init.c
@@ -250,20 +250,9 @@
* 3,2 - level page tables where we don't have
* puds,pmds, so pgd_populate(), pud_populate()
* is noops.
- *
- * The ifndef is required to avoid build breakage.
- *
- * With 5level-fixup.h, pgd_populate() is not nop and
- * we reference kasan_early_shadow_p4d. It's not defined
- * unless 5-level paging enabled.
- *
- * The ifndef can be dropped once all KASAN-enabled
- * architectures will switch to pgtable-nop4d.h.
*/
-#ifndef __ARCH_HAS_5LEVEL_HACK
pgd_populate(&init_mm, pgd,
lm_alias(kasan_early_shadow_p4d));
-#endif
p4d = p4d_offset(pgd, addr);
p4d_populate(&init_mm, p4d,
lm_alias(kasan_early_shadow_pud));
diff --git a/mm/kasan/kasan.h b/mm/kasan/kasan.h
index 35cff6b..ac49945 100644
--- a/mm/kasan/kasan.h
+++ b/mm/kasan/kasan.h
@@ -17,14 +17,17 @@
#define KASAN_PAGE_REDZONE 0xFE /* redzone for kmalloc_large allocations */
#define KASAN_KMALLOC_REDZONE 0xFC /* redzone inside slub object */
#define KASAN_KMALLOC_FREE 0xFB /* object was freed (kmem_cache_free/kfree) */
+#define KASAN_KMALLOC_FREETRACK 0xFA /* object was freed and has free track set */
#else
#define KASAN_FREE_PAGE KASAN_TAG_INVALID
#define KASAN_PAGE_REDZONE KASAN_TAG_INVALID
#define KASAN_KMALLOC_REDZONE KASAN_TAG_INVALID
#define KASAN_KMALLOC_FREE KASAN_TAG_INVALID
+#define KASAN_KMALLOC_FREETRACK KASAN_TAG_INVALID
#endif
-#define KASAN_GLOBAL_REDZONE 0xFA /* redzone for global variable */
+#define KASAN_GLOBAL_REDZONE 0xF9 /* redzone for global variable */
+#define KASAN_VMALLOC_INVALID 0xF8 /* unallocated space in vmapped page */
/*
* Stack redzone shadow values
@@ -103,7 +106,15 @@
struct kasan_alloc_meta {
struct kasan_track alloc_track;
+#ifdef CONFIG_KASAN_GENERIC
+ /*
+ * call_rcu() call stack is stored into struct kasan_alloc_meta.
+ * The free stack is stored into struct kasan_free_meta.
+ */
+ depot_stack_handle_t aux_stack[2];
+#else
struct kasan_track free_track[KASAN_NR_FREE_STACKS];
+#endif
#ifdef CONFIG_KASAN_SW_TAGS_IDENTIFY
u8 free_pointer_tag[KASAN_NR_FREE_STACKS];
u8 free_track_idx;
@@ -118,6 +129,9 @@
* Otherwise it might be used for the allocator freelist.
*/
struct qlist_node quarantine_link;
+#ifdef CONFIG_KASAN_GENERIC
+ struct kasan_track free_track;
+#endif
};
struct kasan_alloc_meta *get_alloc_info(struct kmem_cache *cache,
@@ -152,12 +166,18 @@
void *find_first_bad_addr(void *addr, size_t size);
const char *get_bug_type(struct kasan_access_info *info);
-void kasan_report(unsigned long addr, size_t size,
+bool kasan_report(unsigned long addr, size_t size,
bool is_write, unsigned long ip);
void kasan_report_invalid_free(void *object, unsigned long ip);
struct page *kasan_addr_to_page(const void *addr);
+depot_stack_handle_t kasan_save_stack(gfp_t flags);
+void kasan_set_track(struct kasan_track *track, gfp_t flags);
+void kasan_set_free_info(struct kmem_cache *cache, void *object, u8 tag);
+struct kasan_track *kasan_get_free_track(struct kmem_cache *cache,
+ void *object, u8 tag);
+
#if defined(CONFIG_KASAN_GENERIC) && \
(defined(CONFIG_SLAB) || defined(CONFIG_SLUB))
void quarantine_put(struct kasan_free_meta *info, struct kmem_cache *cache);
@@ -211,8 +231,6 @@
asmlinkage void kasan_unpoison_task_stack_below(const void *watermark);
void __asan_register_globals(struct kasan_global *globals, size_t size);
void __asan_unregister_globals(struct kasan_global *globals, size_t size);
-void __asan_loadN(unsigned long addr, size_t size);
-void __asan_storeN(unsigned long addr, size_t size);
void __asan_handle_no_return(void);
void __asan_alloca_poison(unsigned long addr, size_t size);
void __asan_allocas_unpoison(const void *stack_top, const void *stack_bottom);
@@ -227,6 +245,8 @@
void __asan_store8(unsigned long addr);
void __asan_load16(unsigned long addr);
void __asan_store16(unsigned long addr);
+void __asan_loadN(unsigned long addr, size_t size);
+void __asan_storeN(unsigned long addr, size_t size);
void __asan_load1_noabort(unsigned long addr);
void __asan_store1_noabort(unsigned long addr);
@@ -238,6 +258,21 @@
void __asan_store8_noabort(unsigned long addr);
void __asan_load16_noabort(unsigned long addr);
void __asan_store16_noabort(unsigned long addr);
+void __asan_loadN_noabort(unsigned long addr, size_t size);
+void __asan_storeN_noabort(unsigned long addr, size_t size);
+
+void __asan_report_load1_noabort(unsigned long addr);
+void __asan_report_store1_noabort(unsigned long addr);
+void __asan_report_load2_noabort(unsigned long addr);
+void __asan_report_store2_noabort(unsigned long addr);
+void __asan_report_load4_noabort(unsigned long addr);
+void __asan_report_store4_noabort(unsigned long addr);
+void __asan_report_load8_noabort(unsigned long addr);
+void __asan_report_store8_noabort(unsigned long addr);
+void __asan_report_load16_noabort(unsigned long addr);
+void __asan_report_store16_noabort(unsigned long addr);
+void __asan_report_load_n_noabort(unsigned long addr, size_t size);
+void __asan_report_store_n_noabort(unsigned long addr, size_t size);
void __asan_set_shadow_00(const void *addr, size_t size);
void __asan_set_shadow_f1(const void *addr, size_t size);
@@ -246,4 +281,19 @@
void __asan_set_shadow_f5(const void *addr, size_t size);
void __asan_set_shadow_f8(const void *addr, size_t size);
+void __hwasan_load1_noabort(unsigned long addr);
+void __hwasan_store1_noabort(unsigned long addr);
+void __hwasan_load2_noabort(unsigned long addr);
+void __hwasan_store2_noabort(unsigned long addr);
+void __hwasan_load4_noabort(unsigned long addr);
+void __hwasan_store4_noabort(unsigned long addr);
+void __hwasan_load8_noabort(unsigned long addr);
+void __hwasan_store8_noabort(unsigned long addr);
+void __hwasan_load16_noabort(unsigned long addr);
+void __hwasan_store16_noabort(unsigned long addr);
+void __hwasan_loadN_noabort(unsigned long addr, size_t size);
+void __hwasan_storeN_noabort(unsigned long addr, size_t size);
+
+void __hwasan_tag_memory(unsigned long addr, u8 tag, unsigned long size);
+
#endif
diff --git a/mm/kasan/quarantine.c b/mm/kasan/quarantine.c
index 978bc4a..0e3f849 100644
--- a/mm/kasan/quarantine.c
+++ b/mm/kasan/quarantine.c
@@ -29,6 +29,7 @@
#include <linux/srcu.h>
#include <linux/string.h>
#include <linux/types.h>
+#include <linux/cpuhotplug.h>
#include "../slab.h"
#include "kasan.h"
@@ -43,6 +44,7 @@
struct qlist_node *head;
struct qlist_node *tail;
size_t bytes;
+ bool offline;
};
#define QLIST_INIT { NULL, NULL, 0 }
@@ -145,6 +147,7 @@
if (IS_ENABLED(CONFIG_SLAB))
local_irq_save(flags);
+ *(u8 *)kasan_mem_to_shadow(object) = KASAN_KMALLOC_FREE;
___cache_free(cache, object, _THIS_IP_);
if (IS_ENABLED(CONFIG_SLAB))
@@ -187,6 +190,10 @@
local_irq_save(flags);
q = this_cpu_ptr(&cpu_quarantine);
+ if (q->offline) {
+ local_irq_restore(flags);
+ return;
+ }
qlist_put(q, &info->quarantine_link, cache->size);
if (unlikely(q->bytes > QUARANTINE_PERCPU_SIZE)) {
qlist_move_all(q, &temp);
@@ -327,3 +334,36 @@
synchronize_srcu(&remove_cache_srcu);
}
+
+static int kasan_cpu_online(unsigned int cpu)
+{
+ this_cpu_ptr(&cpu_quarantine)->offline = false;
+ return 0;
+}
+
+static int kasan_cpu_offline(unsigned int cpu)
+{
+ struct qlist_head *q;
+
+ q = this_cpu_ptr(&cpu_quarantine);
+ /* Ensure the ordering between the writing to q->offline and
+ * qlist_free_all. Otherwise, cpu_quarantine may be corrupted
+ * by interrupt.
+ */
+ WRITE_ONCE(q->offline, true);
+ barrier();
+ qlist_free_all(q, NULL);
+ return 0;
+}
+
+static int __init kasan_cpu_quarantine_init(void)
+{
+ int ret = 0;
+
+ ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "mm/kasan:online",
+ kasan_cpu_online, kasan_cpu_offline);
+ if (ret < 0)
+ pr_err("kasan cpu quarantine register failed [%d]\n", ret);
+ return ret;
+}
+late_initcall(kasan_cpu_quarantine_init);
diff --git a/mm/kasan/report.c b/mm/kasan/report.c
index 6217821..00a53f1 100644
--- a/mm/kasan/report.c
+++ b/mm/kasan/report.c
@@ -29,9 +29,12 @@
#include <linux/kasan.h>
#include <linux/module.h>
#include <linux/sched/task_stack.h>
+#include <linux/uaccess.h>
#include <asm/sections.h>
+#include <kunit/test.h>
+
#include "kasan.h"
#include "../slab.h"
@@ -92,20 +95,33 @@
pr_err("==================================================================\n");
add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE);
spin_unlock_irqrestore(&report_lock, *flags);
- if (panic_on_warn)
+ if (panic_on_warn && !test_bit(KASAN_BIT_MULTI_SHOT, &kasan_flags)) {
+ /*
+ * This thread may hit another WARN() in the panic path.
+ * Resetting this prevents additional WARN() from panicking the
+ * system on this thread. Other threads are blocked by the
+ * panic_mutex in panic().
+ */
+ panic_on_warn = 0;
panic("panic_on_warn set ...\n");
+ }
kasan_enable_current();
}
+static void print_stack(depot_stack_handle_t stack)
+{
+ unsigned long *entries;
+ unsigned int nr_entries;
+
+ nr_entries = stack_depot_fetch(stack, &entries);
+ stack_trace_print(entries, nr_entries, 0);
+}
+
static void print_track(struct kasan_track *track, const char *prefix)
{
pr_err("%s by task %u:\n", prefix, track->pid);
if (track->stack) {
- unsigned long *entries;
- unsigned int nr_entries;
-
- nr_entries = stack_depot_fetch(track->stack, &entries);
- stack_trace_print(entries, nr_entries, 0);
+ print_stack(track->stack);
} else {
pr_err("(stack is not available)\n");
}
@@ -151,26 +167,6 @@
(void *)(object_addr + cache->object_size));
}
-static struct kasan_track *kasan_get_free_track(struct kmem_cache *cache,
- void *object, u8 tag)
-{
- struct kasan_alloc_meta *alloc_meta;
- int i = 0;
-
- alloc_meta = get_alloc_info(cache, object);
-
-#ifdef CONFIG_KASAN_SW_TAGS_IDENTIFY
- for (i = 0; i < KASAN_NR_FREE_STACKS; i++) {
- if (alloc_meta->free_pointer_tag[i] == tag)
- break;
- }
- if (i == KASAN_NR_FREE_STACKS)
- i = alloc_meta->free_track_idx;
-#endif
-
- return &alloc_meta->free_track[i];
-}
-
static void describe_object(struct kmem_cache *cache, void *object,
const void *addr, u8 tag)
{
@@ -182,8 +178,23 @@
print_track(&alloc_info->alloc_track, "Allocated");
pr_err("\n");
free_track = kasan_get_free_track(cache, object, tag);
- print_track(free_track, "Freed");
- pr_err("\n");
+ if (free_track) {
+ print_track(free_track, "Freed");
+ pr_err("\n");
+ }
+
+#ifdef CONFIG_KASAN_GENERIC
+ if (alloc_info->aux_stack[0]) {
+ pr_err("Last call_rcu():\n");
+ print_stack(alloc_info->aux_stack[0]);
+ pr_err("\n");
+ }
+ if (alloc_info->aux_stack[1]) {
+ pr_err("Second to last call_rcu():\n");
+ print_stack(alloc_info->aux_stack[1]);
+ pr_err("\n");
+ }
+#endif
}
describe_object_addr(cache, object, addr);
@@ -455,12 +466,37 @@
return !test_and_set_bit(KASAN_BIT_REPORTED, &kasan_flags);
}
+#if IS_ENABLED(CONFIG_KUNIT)
+static void kasan_update_kunit_status(struct kunit *cur_test)
+{
+ struct kunit_resource *resource;
+ struct kunit_kasan_expectation *kasan_data;
+
+ resource = kunit_find_named_resource(cur_test, "kasan_data");
+
+ if (!resource) {
+ kunit_set_failure(cur_test);
+ return;
+ }
+
+ kasan_data = (struct kunit_kasan_expectation *)resource->data;
+ kasan_data->report_found = true;
+ kunit_put_resource(resource);
+}
+#endif /* IS_ENABLED(CONFIG_KUNIT) */
+
void kasan_report_invalid_free(void *object, unsigned long ip)
{
unsigned long flags;
u8 tag = get_tag(object);
object = reset_tag(object);
+
+#if IS_ENABLED(CONFIG_KUNIT)
+ if (current->kunit_test)
+ kasan_update_kunit_status(current->kunit_test);
+#endif /* IS_ENABLED(CONFIG_KUNIT) */
+
start_report(&flags);
pr_err("BUG: KASAN: double-free or invalid-free in %pS\n", (void *)ip);
print_tags(tag, object);
@@ -471,15 +507,18 @@
end_report(&flags);
}
-void __kasan_report(unsigned long addr, size_t size, bool is_write, unsigned long ip)
+static void __kasan_report(unsigned long addr, size_t size, bool is_write,
+ unsigned long ip)
{
struct kasan_access_info info;
void *tagged_addr;
void *untagged_addr;
unsigned long flags;
- if (likely(!report_enabled()))
- return;
+#if IS_ENABLED(CONFIG_KUNIT)
+ if (current->kunit_test)
+ kasan_update_kunit_status(current->kunit_test);
+#endif /* IS_ENABLED(CONFIG_KUNIT) */
disable_trace_on_warning();
@@ -512,3 +551,59 @@
end_report(&flags);
}
+
+bool kasan_report(unsigned long addr, size_t size, bool is_write,
+ unsigned long ip)
+{
+ unsigned long flags = user_access_save();
+ bool ret = false;
+
+ if (likely(report_enabled())) {
+ __kasan_report(addr, size, is_write, ip);
+ ret = true;
+ }
+
+ user_access_restore(flags);
+
+ return ret;
+}
+
+#ifdef CONFIG_KASAN_INLINE
+/*
+ * With CONFIG_KASAN_INLINE, accesses to bogus pointers (outside the high
+ * canonical half of the address space) cause out-of-bounds shadow memory reads
+ * before the actual access. For addresses in the low canonical half of the
+ * address space, as well as most non-canonical addresses, that out-of-bounds
+ * shadow memory access lands in the non-canonical part of the address space.
+ * Help the user figure out what the original bogus pointer was.
+ */
+void kasan_non_canonical_hook(unsigned long addr)
+{
+ unsigned long orig_addr;
+ const char *bug_type;
+
+ if (addr < KASAN_SHADOW_OFFSET)
+ return;
+
+ orig_addr = (addr - KASAN_SHADOW_OFFSET) << KASAN_SHADOW_SCALE_SHIFT;
+ /*
+ * For faults near the shadow address for NULL, we can be fairly certain
+ * that this is a KASAN shadow memory access.
+ * For faults that correspond to shadow for low canonical addresses, we
+ * can still be pretty sure - that shadow region is a fairly narrow
+ * chunk of the non-canonical address space.
+ * But faults that look like shadow for non-canonical addresses are a
+ * really large chunk of the address space. In that case, we still
+ * print the decoded address, but make it clear that this is not
+ * necessarily what's actually going on.
+ */
+ if (orig_addr < PAGE_SIZE)
+ bug_type = "null-ptr-deref";
+ else if (orig_addr < TASK_SIZE)
+ bug_type = "probably user-memory-access";
+ else
+ bug_type = "maybe wild-memory-access";
+ pr_alert("KASAN: %s in range [0x%016lx-0x%016lx]\n", bug_type,
+ orig_addr, orig_addr + KASAN_SHADOW_MASK);
+}
+#endif
diff --git a/mm/kasan/tags.c b/mm/kasan/tags.c
index caf4efd..e02a36a 100644
--- a/mm/kasan/tags.c
+++ b/mm/kasan/tags.c
@@ -85,6 +85,9 @@
if (unlikely(size == 0))
return true;
+ if (unlikely(addr + size < addr))
+ return !kasan_report(addr, size, write, ret_ip);
+
tag = get_tag((const void *)addr);
/*
@@ -110,15 +113,13 @@
untagged_addr = reset_tag((const void *)addr);
if (unlikely(untagged_addr <
kasan_shadow_to_mem((void *)KASAN_SHADOW_START))) {
- kasan_report(addr, size, write, ret_ip);
- return false;
+ return !kasan_report(addr, size, write, ret_ip);
}
shadow_first = kasan_mem_to_shadow(untagged_addr);
shadow_last = kasan_mem_to_shadow(untagged_addr + size - 1);
for (shadow = shadow_first; shadow <= shadow_last; shadow++) {
if (*shadow != tag) {
- kasan_report(addr, size, write, ret_ip);
- return false;
+ return !kasan_report(addr, size, write, ret_ip);
}
}
@@ -160,3 +161,40 @@
kasan_poison_shadow((void *)addr, size, tag);
}
EXPORT_SYMBOL(__hwasan_tag_memory);
+
+void kasan_set_free_info(struct kmem_cache *cache,
+ void *object, u8 tag)
+{
+ struct kasan_alloc_meta *alloc_meta;
+ u8 idx = 0;
+
+ alloc_meta = get_alloc_info(cache, object);
+
+#ifdef CONFIG_KASAN_SW_TAGS_IDENTIFY
+ idx = alloc_meta->free_track_idx;
+ alloc_meta->free_pointer_tag[idx] = tag;
+ alloc_meta->free_track_idx = (idx + 1) % KASAN_NR_FREE_STACKS;
+#endif
+
+ kasan_set_track(&alloc_meta->free_track[idx], GFP_NOWAIT);
+}
+
+struct kasan_track *kasan_get_free_track(struct kmem_cache *cache,
+ void *object, u8 tag)
+{
+ struct kasan_alloc_meta *alloc_meta;
+ int i = 0;
+
+ alloc_meta = get_alloc_info(cache, object);
+
+#ifdef CONFIG_KASAN_SW_TAGS_IDENTIFY
+ for (i = 0; i < KASAN_NR_FREE_STACKS; i++) {
+ if (alloc_meta->free_pointer_tag[i] == tag)
+ break;
+ }
+ if (i == KASAN_NR_FREE_STACKS)
+ i = alloc_meta->free_track_idx;
+#endif
+
+ return &alloc_meta->free_track[i];
+}
diff --git a/mm/kasan/tags_report.c b/mm/kasan/tags_report.c
index 969ae08..bee4371 100644
--- a/mm/kasan/tags_report.c
+++ b/mm/kasan/tags_report.c
@@ -60,6 +60,17 @@
}
#endif
+ /*
+ * If access_size is a negative number, then it has reason to be
+ * defined as out-of-bounds bug type.
+ *
+ * Casting negative numbers to size_t would indeed turn up as
+ * a large size_t and its value will be larger than ULONG_MAX/2,
+ * so that this can qualify as out-of-bounds.
+ */
+ if (info->access_addr + info->access_size < info->access_addr)
+ return "out-of-bounds";
+
return "invalid-access";
}