The current code only does the check if kasan is disabled for hw_tags
mode. Here add the conditional checks for functional functions of
generic mode and sw_tags mode.

This is prepared for later adding kernel parameter kasan=on|off for
all kasan modes.

Signed-off-by: Baoquan He <b...@redhat.com>
---
 mm/kasan/generic.c    | 20 ++++++++++++++++++--
 mm/kasan/init.c       |  6 ++++++
 mm/kasan/quarantine.c |  3 +++
 mm/kasan/report.c     |  4 +++-
 mm/kasan/shadow.c     | 23 ++++++++++++++++++++++-
 mm/kasan/sw_tags.c    |  3 +++
 6 files changed, 55 insertions(+), 4 deletions(-)

diff --git a/mm/kasan/generic.c b/mm/kasan/generic.c
index d54e89f8c3e7..8daea5892754 100644
--- a/mm/kasan/generic.c
+++ b/mm/kasan/generic.c
@@ -165,6 +165,9 @@ static __always_inline bool check_region_inline(const void 
*addr,
                                                size_t size, bool write,
                                                unsigned long ret_ip)
 {
+       if (!kasan_enabled())
+               return true;
+
        if (!kasan_arch_is_ready())
                return true;
 
@@ -203,12 +206,13 @@ bool kasan_byte_accessible(const void *addr)
 
 void kasan_cache_shrink(struct kmem_cache *cache)
 {
-       kasan_quarantine_remove_cache(cache);
+       if (kasan_enabled())
+               kasan_quarantine_remove_cache(cache);
 }
 
 void kasan_cache_shutdown(struct kmem_cache *cache)
 {
-       if (!__kmem_cache_empty(cache))
+       if (kasan_enabled() && !__kmem_cache_empty(cache))
                kasan_quarantine_remove_cache(cache);
 }
 
@@ -228,6 +232,9 @@ void __asan_register_globals(void *ptr, ssize_t size)
        int i;
        struct kasan_global *globals = ptr;
 
+       if (!kasan_enabled())
+               return;
+
        for (i = 0; i < size; i++)
                register_global(&globals[i]);
 }
@@ -358,6 +365,9 @@ void kasan_cache_create(struct kmem_cache *cache, unsigned 
int *size,
        unsigned int rem_free_meta_size;
        unsigned int orig_alloc_meta_offset;
 
+       if (!kasan_enabled())
+               return;
+
        if (!kasan_requires_meta())
                return;
 
@@ -510,6 +520,9 @@ size_t kasan_metadata_size(struct kmem_cache *cache, bool 
in_object)
 {
        struct kasan_cache *info = &cache->kasan_info;
 
+       if (!kasan_enabled())
+               return 0;
+
        if (!kasan_requires_meta())
                return 0;
 
@@ -535,6 +548,9 @@ void kasan_record_aux_stack(void *addr)
        struct kasan_alloc_meta *alloc_meta;
        void *object;
 
+       if (!kasan_enabled())
+               return;
+
        if (is_kfence_address(addr) || !slab)
                return;
 
diff --git a/mm/kasan/init.c b/mm/kasan/init.c
index ced6b29fcf76..43d95f329675 100644
--- a/mm/kasan/init.c
+++ b/mm/kasan/init.c
@@ -449,6 +449,9 @@ void kasan_remove_zero_shadow(void *start, unsigned long 
size)
        unsigned long addr, end, next;
        pgd_t *pgd;
 
+       if (!kasan_enabled())
+               return;
+
        addr = (unsigned long)kasan_mem_to_shadow(start);
        end = addr + (size >> KASAN_SHADOW_SCALE_SHIFT);
 
@@ -484,6 +487,9 @@ int kasan_add_zero_shadow(void *start, unsigned long size)
        int ret;
        void *shadow_start, *shadow_end;
 
+       if (!kasan_enabled())
+               return 0;
+
        shadow_start = kasan_mem_to_shadow(start);
        shadow_end = shadow_start + (size >> KASAN_SHADOW_SCALE_SHIFT);
 
diff --git a/mm/kasan/quarantine.c b/mm/kasan/quarantine.c
index 6958aa713c67..a6dc2c3d8a15 100644
--- a/mm/kasan/quarantine.c
+++ b/mm/kasan/quarantine.c
@@ -405,6 +405,9 @@ static int __init kasan_cpu_quarantine_init(void)
 {
        int ret = 0;
 
+       if (!kasan_enabled())
+               return 0;
+
        ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "mm/kasan:online",
                                kasan_cpu_online, kasan_cpu_offline);
        if (ret < 0)
diff --git a/mm/kasan/report.c b/mm/kasan/report.c
index 62c01b4527eb..884357fa74ed 100644
--- a/mm/kasan/report.c
+++ b/mm/kasan/report.c
@@ -576,7 +576,9 @@ bool kasan_report(const void *addr, size_t size, bool 
is_write,
        unsigned long irq_flags;
        struct kasan_report_info info;
 
-       if (unlikely(report_suppressed_sw()) || unlikely(!report_enabled())) {
+       if (unlikely(report_suppressed_sw()) ||
+           unlikely(!report_enabled()) ||
+           !kasan_enabled()) {
                ret = false;
                goto out;
        }
diff --git a/mm/kasan/shadow.c b/mm/kasan/shadow.c
index d2c70cd2afb1..637f2d02d2a3 100644
--- a/mm/kasan/shadow.c
+++ b/mm/kasan/shadow.c
@@ -125,6 +125,9 @@ void kasan_poison(const void *addr, size_t size, u8 value, 
bool init)
 {
        void *shadow_start, *shadow_end;
 
+       if (!kasan_enabled())
+               return;
+
        if (!kasan_arch_is_ready())
                return;
 
@@ -150,6 +153,9 @@ EXPORT_SYMBOL_GPL(kasan_poison);
 #ifdef CONFIG_KASAN_GENERIC
 void kasan_poison_last_granule(const void *addr, size_t size)
 {
+       if (!kasan_enabled())
+               return;
+
        if (!kasan_arch_is_ready())
                return;
 
@@ -164,6 +170,8 @@ void kasan_unpoison(const void *addr, size_t size, bool 
init)
 {
        u8 tag = get_tag(addr);
 
+       if (!kasan_enabled())
+               return;
        /*
         * Perform shadow offset calculation based on untagged address, as
         * some of the callers (e.g. kasan_unpoison_new_object) pass tagged
@@ -277,7 +285,8 @@ static int __meminit kasan_mem_notifier(struct 
notifier_block *nb,
 
 static int __init kasan_memhotplug_init(void)
 {
-       hotplug_memory_notifier(kasan_mem_notifier, DEFAULT_CALLBACK_PRI);
+       if (kasan_enabled())
+               hotplug_memory_notifier(kasan_mem_notifier, 
DEFAULT_CALLBACK_PRI);
 
        return 0;
 }
@@ -390,6 +399,9 @@ int kasan_populate_vmalloc(unsigned long addr, unsigned 
long size)
        unsigned long shadow_start, shadow_end;
        int ret;
 
+       if (!kasan_enabled())
+               return 0;
+
        if (!kasan_arch_is_ready())
                return 0;
 
@@ -560,6 +572,9 @@ void kasan_release_vmalloc(unsigned long start, unsigned 
long end,
        unsigned long region_start, region_end;
        unsigned long size;
 
+       if (!kasan_enabled())
+               return;
+
        if (!kasan_arch_is_ready())
                return;
 
@@ -655,6 +670,9 @@ int kasan_alloc_module_shadow(void *addr, size_t size, 
gfp_t gfp_mask)
        size_t shadow_size;
        unsigned long shadow_start;
 
+       if (!kasan_enabled())
+               return 0;
+
        shadow_start = (unsigned long)kasan_mem_to_shadow(addr);
        scaled_size = (size + KASAN_GRANULE_SIZE - 1) >>
                                KASAN_SHADOW_SCALE_SHIFT;
@@ -691,6 +709,9 @@ int kasan_alloc_module_shadow(void *addr, size_t size, 
gfp_t gfp_mask)
 
 void kasan_free_module_shadow(const struct vm_struct *vm)
 {
+       if (!kasan_enabled())
+               return;
+
        if (IS_ENABLED(CONFIG_UML))
                return;
 
diff --git a/mm/kasan/sw_tags.c b/mm/kasan/sw_tags.c
index b9382b5b6a37..01f19bc4a326 100644
--- a/mm/kasan/sw_tags.c
+++ b/mm/kasan/sw_tags.c
@@ -78,6 +78,9 @@ bool kasan_check_range(const void *addr, size_t size, bool 
write,
        u8 *shadow_first, *shadow_last, *shadow;
        void *untagged_addr;
 
+       if (!kasan_enabled())
+               return true;
+
        if (unlikely(size == 0))
                return true;
 
-- 
2.41.0


Reply via email to