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-rw-r--r--mm/kasan/common.c8
-rw-r--r--mm/kasan/hw_tags.c32
-rw-r--r--mm/kasan/kasan.h3
-rw-r--r--mm/kasan/report.c12
4 files changed, 37 insertions, 18 deletions
diff --git a/mm/kasan/common.c b/mm/kasan/common.c
index 78be2beb7453..69f583855c8b 100644
--- a/mm/kasan/common.c
+++ b/mm/kasan/common.c
@@ -344,7 +344,7 @@ static inline bool ____kasan_slab_free(struct kmem_cache *cache, void *object,
if (unlikely(nearest_obj(cache, virt_to_slab(object), object) !=
object)) {
- kasan_report_invalid_free(tagged_object, ip);
+ kasan_report_invalid_free(tagged_object, ip, KASAN_REPORT_INVALID_FREE);
return true;
}
@@ -353,7 +353,7 @@ static inline bool ____kasan_slab_free(struct kmem_cache *cache, void *object,
return false;
if (!kasan_byte_accessible(tagged_object)) {
- kasan_report_invalid_free(tagged_object, ip);
+ kasan_report_invalid_free(tagged_object, ip, KASAN_REPORT_DOUBLE_FREE);
return true;
}
@@ -378,12 +378,12 @@ bool __kasan_slab_free(struct kmem_cache *cache, void *object,
static inline bool ____kasan_kfree_large(void *ptr, unsigned long ip)
{
if (ptr != page_address(virt_to_head_page(ptr))) {
- kasan_report_invalid_free(ptr, ip);
+ kasan_report_invalid_free(ptr, ip, KASAN_REPORT_INVALID_FREE);
return true;
}
if (!kasan_byte_accessible(ptr)) {
- kasan_report_invalid_free(ptr, ip);
+ kasan_report_invalid_free(ptr, ip, KASAN_REPORT_DOUBLE_FREE);
return true;
}
diff --git a/mm/kasan/hw_tags.c b/mm/kasan/hw_tags.c
index 9e1b6544bfa8..9ad8eff71b28 100644
--- a/mm/kasan/hw_tags.c
+++ b/mm/kasan/hw_tags.c
@@ -257,27 +257,37 @@ static void unpoison_vmalloc_pages(const void *addr, u8 tag)
}
}
+static void init_vmalloc_pages(const void *start, unsigned long size)
+{
+ const void *addr;
+
+ for (addr = start; addr < start + size; addr += PAGE_SIZE) {
+ struct page *page = virt_to_page(addr);
+
+ clear_highpage_kasan_tagged(page);
+ }
+}
+
void *__kasan_unpoison_vmalloc(const void *start, unsigned long size,
kasan_vmalloc_flags_t flags)
{
u8 tag;
unsigned long redzone_start, redzone_size;
- if (!kasan_vmalloc_enabled())
- return (void *)start;
-
- if (!is_vmalloc_or_module_addr(start))
+ if (!kasan_vmalloc_enabled() || !is_vmalloc_or_module_addr(start)) {
+ if (flags & KASAN_VMALLOC_INIT)
+ init_vmalloc_pages(start, size);
return (void *)start;
+ }
/*
- * Skip unpoisoning and assigning a pointer tag for non-VM_ALLOC
- * mappings as:
+ * Don't tag non-VM_ALLOC mappings, as:
*
* 1. Unlike the software KASAN modes, hardware tag-based KASAN only
* supports tagging physical memory. Therefore, it can only tag a
* single mapping of normal physical pages.
* 2. Hardware tag-based KASAN can only tag memory mapped with special
- * mapping protection bits, see arch_vmalloc_pgprot_modify().
+ * mapping protection bits, see arch_vmap_pgprot_tagged().
* As non-VM_ALLOC mappings can be mapped outside of vmalloc code,
* providing these bits would require tracking all non-VM_ALLOC
* mappers.
@@ -289,15 +299,19 @@ void *__kasan_unpoison_vmalloc(const void *start, unsigned long size,
*
* For non-VM_ALLOC allocations, page_alloc memory is tagged as usual.
*/
- if (!(flags & KASAN_VMALLOC_VM_ALLOC))
+ if (!(flags & KASAN_VMALLOC_VM_ALLOC)) {
+ WARN_ON(flags & KASAN_VMALLOC_INIT);
return (void *)start;
+ }
/*
* Don't tag executable memory.
* The kernel doesn't tolerate having the PC register tagged.
*/
- if (!(flags & KASAN_VMALLOC_PROT_NORMAL))
+ if (!(flags & KASAN_VMALLOC_PROT_NORMAL)) {
+ WARN_ON(flags & KASAN_VMALLOC_INIT);
return (void *)start;
+ }
tag = kasan_random_tag();
start = set_tag(start, tag);
diff --git a/mm/kasan/kasan.h b/mm/kasan/kasan.h
index 610d60d6e5b8..01c03e45acd4 100644
--- a/mm/kasan/kasan.h
+++ b/mm/kasan/kasan.h
@@ -125,6 +125,7 @@ static inline bool kasan_sync_fault_possible(void)
enum kasan_report_type {
KASAN_REPORT_ACCESS,
KASAN_REPORT_INVALID_FREE,
+ KASAN_REPORT_DOUBLE_FREE,
};
struct kasan_report_info {
@@ -277,7 +278,7 @@ static inline void kasan_print_address_stack_frame(const void *addr) { }
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);
+void kasan_report_invalid_free(void *object, unsigned long ip, enum kasan_report_type type);
struct page *kasan_addr_to_page(const void *addr);
struct slab *kasan_addr_to_slab(const void *addr);
diff --git a/mm/kasan/report.c b/mm/kasan/report.c
index b341a191651d..fe3f606b3a98 100644
--- a/mm/kasan/report.c
+++ b/mm/kasan/report.c
@@ -176,8 +176,12 @@ static void end_report(unsigned long *flags, void *addr)
static void print_error_description(struct kasan_report_info *info)
{
if (info->type == KASAN_REPORT_INVALID_FREE) {
- pr_err("BUG: KASAN: double-free or invalid-free in %pS\n",
- (void *)info->ip);
+ pr_err("BUG: KASAN: invalid-free in %pS\n", (void *)info->ip);
+ return;
+ }
+
+ if (info->type == KASAN_REPORT_DOUBLE_FREE) {
+ pr_err("BUG: KASAN: double-free in %pS\n", (void *)info->ip);
return;
}
@@ -433,7 +437,7 @@ static void print_report(struct kasan_report_info *info)
}
}
-void kasan_report_invalid_free(void *ptr, unsigned long ip)
+void kasan_report_invalid_free(void *ptr, unsigned long ip, enum kasan_report_type type)
{
unsigned long flags;
struct kasan_report_info info;
@@ -448,7 +452,7 @@ void kasan_report_invalid_free(void *ptr, unsigned long ip)
start_report(&flags, true);
- info.type = KASAN_REPORT_INVALID_FREE;
+ info.type = type;
info.access_addr = ptr;
info.first_bad_addr = kasan_reset_tag(ptr);
info.access_size = 0;