From: Andrey Konovalov <[email protected]>
Right now, KASAN uses the kasan_report_type enum to describe report types.
As this enum only has two options, replace it with a bool variable.
Also, unify printing report header for invalid-free and other bug types
in print_error_description().
Signed-off-by: Andrey Konovalov <[email protected]>
---
mm/kasan/kasan.h | 7 +------
mm/kasan/report.c | 16 +++++++---------
2 files changed, 8 insertions(+), 15 deletions(-)
diff --git a/mm/kasan/kasan.h b/mm/kasan/kasan.h
index e8329935fbfb..f696d50b09fb 100644
--- a/mm/kasan/kasan.h
+++ b/mm/kasan/kasan.h
@@ -146,16 +146,11 @@ static inline bool kasan_requires_meta(void)
#define META_MEM_BYTES_PER_ROW (META_BYTES_PER_ROW * KASAN_GRANULE_SIZE)
#define META_ROWS_AROUND_ADDR 2
-enum kasan_report_type {
- KASAN_REPORT_ACCESS,
- KASAN_REPORT_INVALID_FREE,
-};
-
struct kasan_report_info {
- enum kasan_report_type type;
void *access_addr;
void *first_bad_addr;
size_t access_size;
+ bool is_free;
bool is_write;
unsigned long ip;
};
diff --git a/mm/kasan/report.c b/mm/kasan/report.c
index f951fd39db74..7269b6249488 100644
--- a/mm/kasan/report.c
+++ b/mm/kasan/report.c
@@ -175,14 +175,12 @@ 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);
- return;
- }
+ const char *bug_type = info->is_free ?
+ "double-free or invalid-free" : kasan_get_bug_type(info);
- pr_err("BUG: KASAN: %s in %pS\n",
- kasan_get_bug_type(info), (void *)info->ip);
+ pr_err("BUG: KASAN: %s in %pS\n", bug_type, (void *)info->ip);
+ if (info->is_free)
+ return;
if (info->access_size)
pr_err("%s of size %zu at addr %px by task %s/%d\n",
info->is_write ? "Write" : "Read", info->access_size,
@@ -435,11 +433,11 @@ void kasan_report_invalid_free(void *ptr, unsigned long ip)
start_report(&flags, true);
- info.type = KASAN_REPORT_INVALID_FREE;
info.access_addr = ptr;
info.first_bad_addr = kasan_reset_tag(ptr);
info.access_size = 0;
info.is_write = false;
+ info.is_free = true;
info.ip = ip;
print_report(&info);
@@ -468,11 +466,11 @@ bool kasan_report(unsigned long addr, size_t size, bool is_write,
start_report(&irq_flags, true);
- info.type = KASAN_REPORT_ACCESS;
info.access_addr = ptr;
info.first_bad_addr = kasan_find_first_bad_addr(ptr, size);
info.access_size = size;
info.is_write = is_write;
+ info.is_free = false;
info.ip = ip;
print_report(&info);
--
2.25.1
On Tue, Jun 21, 2022 at 9:17 AM Kuan-Ying Lee
<[email protected]> wrote:
>
> On Tue, 2022-06-14 at 04:14 +0800, [email protected] wrote:
> > From: Andrey Konovalov <[email protected]>
> >
> > Right now, KASAN uses the kasan_report_type enum to describe report
> > types.
> >
> > As this enum only has two options, replace it with a bool variable.
> >
> > Also, unify printing report header for invalid-free and other bug
> > types
> > in print_error_description().
> >
> > Signed-off-by: Andrey Konovalov <[email protected]>
> > ---
> > mm/kasan/kasan.h | 7 +------
> > mm/kasan/report.c | 16 +++++++---------
> > 2 files changed, 8 insertions(+), 15 deletions(-)
> >
> > diff --git a/mm/kasan/kasan.h b/mm/kasan/kasan.h
> > index e8329935fbfb..f696d50b09fb 100644
> > --- a/mm/kasan/kasan.h
> > +++ b/mm/kasan/kasan.h
> > @@ -146,16 +146,11 @@ static inline bool kasan_requires_meta(void)
> > #define META_MEM_BYTES_PER_ROW (META_BYTES_PER_ROW *
> > KASAN_GRANULE_SIZE)
> > #define META_ROWS_AROUND_ADDR 2
> >
> > -enum kasan_report_type {
> > - KASAN_REPORT_ACCESS,
> > - KASAN_REPORT_INVALID_FREE,
> > -};
> > -
> > struct kasan_report_info {
> > - enum kasan_report_type type;
> > void *access_addr;
> > void *first_bad_addr;
> > size_t access_size;
> > + bool is_free;
> > bool is_write;
> > unsigned long ip;
> > };
> > diff --git a/mm/kasan/report.c b/mm/kasan/report.c
> > index f951fd39db74..7269b6249488 100644
> > --- a/mm/kasan/report.c
> > +++ b/mm/kasan/report.c
> > @@ -175,14 +175,12 @@ static void end_report(unsigned long *flags,
> > void *addr)
> >
>
> Hi Andrey,
>
> Do we need to distinguish "double free" case from "invalid free" or
> we just print "double-free or invalid-free"?
>
> I sent a patch[1] to separate double free case from invalid
> free last week and I saw it has been merged into akpm tree.
>
> [1]
> https://lore.kernel.org/linux-mm/[email protected]/
Hi Kuan-Ying,
Yes, thank you for the patch! I will rebase my series onto it.
Thanks!