2022-06-13 21:16:25

by andrey.konovalov

[permalink] [raw]
Subject: [PATCH 07/32] kasan: introduce kasan_get_alloc_track

From: Andrey Konovalov <[email protected]>

Add a kasan_get_alloc_track() helper that fetches alloc_track for a slab
object and use this helper in the common reporting code.

For now, the implementations of this helper are the same for the Generic
and tag-based modes, but they will diverge later in the series.

This change hides references to alloc_meta from the common reporting code.
This is desired as only the Generic mode will be using per-object metadata
after this series.

Signed-off-by: Andrey Konovalov <[email protected]>
---
mm/kasan/generic.c | 14 +++++++++++++-
mm/kasan/kasan.h | 4 +++-
mm/kasan/report.c | 8 ++++----
mm/kasan/tags.c | 14 +++++++++++++-
4 files changed, 33 insertions(+), 7 deletions(-)

diff --git a/mm/kasan/generic.c b/mm/kasan/generic.c
index 98c451a3b01f..f212b9ae57b5 100644
--- a/mm/kasan/generic.c
+++ b/mm/kasan/generic.c
@@ -381,8 +381,20 @@ void kasan_save_free_info(struct kmem_cache *cache,
*(u8 *)kasan_mem_to_shadow(object) = KASAN_SLAB_FREETRACK;
}

+struct kasan_track *kasan_get_alloc_track(struct kmem_cache *cache,
+ void *object)
+{
+ struct kasan_alloc_meta *alloc_meta;
+
+ alloc_meta = kasan_get_alloc_meta(cache, object);
+ if (!alloc_meta)
+ return NULL;
+
+ return &alloc_meta->alloc_track;
+}
+
struct kasan_track *kasan_get_free_track(struct kmem_cache *cache,
- void *object, u8 tag)
+ void *object, u8 tag)
{
if (*(u8 *)kasan_mem_to_shadow(object) != KASAN_SLAB_FREETRACK)
return NULL;
diff --git a/mm/kasan/kasan.h b/mm/kasan/kasan.h
index bcea5ed15631..4005da62a1e1 100644
--- a/mm/kasan/kasan.h
+++ b/mm/kasan/kasan.h
@@ -282,8 +282,10 @@ depot_stack_handle_t kasan_save_stack(gfp_t flags, bool can_alloc);
void kasan_set_track(struct kasan_track *track, gfp_t flags);
void kasan_save_alloc_info(struct kmem_cache *cache, void *object, gfp_t flags);
void kasan_save_free_info(struct kmem_cache *cache, void *object, u8 tag);
+struct kasan_track *kasan_get_alloc_track(struct kmem_cache *cache,
+ void *object);
struct kasan_track *kasan_get_free_track(struct kmem_cache *cache,
- void *object, u8 tag);
+ void *object, u8 tag);

#if defined(CONFIG_KASAN_GENERIC) && \
(defined(CONFIG_SLAB) || defined(CONFIG_SLUB))
diff --git a/mm/kasan/report.c b/mm/kasan/report.c
index 35dd8aeb115c..f951fd39db74 100644
--- a/mm/kasan/report.c
+++ b/mm/kasan/report.c
@@ -251,12 +251,12 @@ static void describe_object_addr(struct kmem_cache *cache, void *object,
static void describe_object_stacks(struct kmem_cache *cache, void *object,
const void *addr, u8 tag)
{
- struct kasan_alloc_meta *alloc_meta;
+ struct kasan_track *alloc_track;
struct kasan_track *free_track;

- alloc_meta = kasan_get_alloc_meta(cache, object);
- if (alloc_meta) {
- print_track(&alloc_meta->alloc_track, "Allocated");
+ alloc_track = kasan_get_alloc_track(cache, object);
+ if (alloc_track) {
+ print_track(alloc_track, "Allocated");
pr_err("\n");
}

diff --git a/mm/kasan/tags.c b/mm/kasan/tags.c
index e0e5de8ce834..7b1fc8e7c99c 100644
--- a/mm/kasan/tags.c
+++ b/mm/kasan/tags.c
@@ -38,8 +38,20 @@ void kasan_save_free_info(struct kmem_cache *cache,
kasan_set_track(&alloc_meta->free_track, GFP_NOWAIT);
}

+struct kasan_track *kasan_get_alloc_track(struct kmem_cache *cache,
+ void *object)
+{
+ struct kasan_alloc_meta *alloc_meta;
+
+ alloc_meta = kasan_get_alloc_meta(cache, object);
+ if (!alloc_meta)
+ return NULL;
+
+ return &alloc_meta->alloc_track;
+}
+
struct kasan_track *kasan_get_free_track(struct kmem_cache *cache,
- void *object, u8 tag)
+ void *object, u8 tag)
{
struct kasan_alloc_meta *alloc_meta;

--
2.25.1


2022-06-20 14:47:51

by Marco Elver

[permalink] [raw]
Subject: Re: [PATCH 07/32] kasan: introduce kasan_get_alloc_track

On Mon, 13 Jun 2022 at 22:16, <[email protected]> wrote:
>
> From: Andrey Konovalov <[email protected]>
>
> Add a kasan_get_alloc_track() helper that fetches alloc_track for a slab
> object and use this helper in the common reporting code.
>
> For now, the implementations of this helper are the same for the Generic
> and tag-based modes, but they will diverge later in the series.
>
> This change hides references to alloc_meta from the common reporting code.
> This is desired as only the Generic mode will be using per-object metadata
> after this series.
>
> Signed-off-by: Andrey Konovalov <[email protected]>

Reviewed-by: Marco Elver <[email protected]>


> ---
> mm/kasan/generic.c | 14 +++++++++++++-
> mm/kasan/kasan.h | 4 +++-
> mm/kasan/report.c | 8 ++++----
> mm/kasan/tags.c | 14 +++++++++++++-
> 4 files changed, 33 insertions(+), 7 deletions(-)
>
> diff --git a/mm/kasan/generic.c b/mm/kasan/generic.c
> index 98c451a3b01f..f212b9ae57b5 100644
> --- a/mm/kasan/generic.c
> +++ b/mm/kasan/generic.c
> @@ -381,8 +381,20 @@ void kasan_save_free_info(struct kmem_cache *cache,
> *(u8 *)kasan_mem_to_shadow(object) = KASAN_SLAB_FREETRACK;
> }
>
> +struct kasan_track *kasan_get_alloc_track(struct kmem_cache *cache,
> + void *object)
> +{
> + struct kasan_alloc_meta *alloc_meta;
> +
> + alloc_meta = kasan_get_alloc_meta(cache, object);
> + if (!alloc_meta)
> + return NULL;
> +
> + return &alloc_meta->alloc_track;
> +}
> +
> struct kasan_track *kasan_get_free_track(struct kmem_cache *cache,
> - void *object, u8 tag)
> + void *object, u8 tag)
> {
> if (*(u8 *)kasan_mem_to_shadow(object) != KASAN_SLAB_FREETRACK)
> return NULL;
> diff --git a/mm/kasan/kasan.h b/mm/kasan/kasan.h
> index bcea5ed15631..4005da62a1e1 100644
> --- a/mm/kasan/kasan.h
> +++ b/mm/kasan/kasan.h
> @@ -282,8 +282,10 @@ depot_stack_handle_t kasan_save_stack(gfp_t flags, bool can_alloc);
> void kasan_set_track(struct kasan_track *track, gfp_t flags);
> void kasan_save_alloc_info(struct kmem_cache *cache, void *object, gfp_t flags);
> void kasan_save_free_info(struct kmem_cache *cache, void *object, u8 tag);
> +struct kasan_track *kasan_get_alloc_track(struct kmem_cache *cache,
> + void *object);
> struct kasan_track *kasan_get_free_track(struct kmem_cache *cache,
> - void *object, u8 tag);
> + void *object, u8 tag);
>
> #if defined(CONFIG_KASAN_GENERIC) && \
> (defined(CONFIG_SLAB) || defined(CONFIG_SLUB))
> diff --git a/mm/kasan/report.c b/mm/kasan/report.c
> index 35dd8aeb115c..f951fd39db74 100644
> --- a/mm/kasan/report.c
> +++ b/mm/kasan/report.c
> @@ -251,12 +251,12 @@ static void describe_object_addr(struct kmem_cache *cache, void *object,
> static void describe_object_stacks(struct kmem_cache *cache, void *object,
> const void *addr, u8 tag)
> {
> - struct kasan_alloc_meta *alloc_meta;
> + struct kasan_track *alloc_track;
> struct kasan_track *free_track;
>
> - alloc_meta = kasan_get_alloc_meta(cache, object);
> - if (alloc_meta) {
> - print_track(&alloc_meta->alloc_track, "Allocated");
> + alloc_track = kasan_get_alloc_track(cache, object);
> + if (alloc_track) {
> + print_track(alloc_track, "Allocated");
> pr_err("\n");
> }
>
> diff --git a/mm/kasan/tags.c b/mm/kasan/tags.c
> index e0e5de8ce834..7b1fc8e7c99c 100644
> --- a/mm/kasan/tags.c
> +++ b/mm/kasan/tags.c
> @@ -38,8 +38,20 @@ void kasan_save_free_info(struct kmem_cache *cache,
> kasan_set_track(&alloc_meta->free_track, GFP_NOWAIT);
> }
>
> +struct kasan_track *kasan_get_alloc_track(struct kmem_cache *cache,
> + void *object)
> +{
> + struct kasan_alloc_meta *alloc_meta;
> +
> + alloc_meta = kasan_get_alloc_meta(cache, object);
> + if (!alloc_meta)
> + return NULL;
> +
> + return &alloc_meta->alloc_track;
> +}
> +
> struct kasan_track *kasan_get_free_track(struct kmem_cache *cache,
> - void *object, u8 tag)
> + void *object, u8 tag)
> {
> struct kasan_alloc_meta *alloc_meta;
>
> --
> 2.25.1
>
> --
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