diff mbox series

[1/2] mm/damon/paddr: fix folio_size() call after folio_put() in damon_pa_young()

Message ID 20230304193949.296391-2-sj@kernel.org
State New
Headers
Series mm/damon/paddr: Fix folio-use-after-put bugs |

Commit Message

SeongJae Park March 4, 2023, 7:39 p.m. UTC 
  damon_pa_young() is accessing a folio via folio_size() after folio_put()
for the folio has invoked.  Fix it.

Fixes: 397b0c3a584b ("mm/damon/paddr: remove folio_sz field from damon_pa_access_chk_result")
Cc: <stable@vger.kernel.org> # 6.3.x
Signed-off-by: SeongJae Park <sj@kernel.org>
---
 mm/damon/paddr.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

Comments

Matthew Wilcox March 5, 2023, midnight UTC | #1 
On Sat, Mar 04, 2023 at 07:39:48PM +0000, SeongJae Park wrote:
> damon_pa_young() is accessing a folio via folio_size() after folio_put()
> for the folio has invoked.  Fix it.
> 
> Fixes: 397b0c3a584b ("mm/damon/paddr: remove folio_sz field from damon_pa_access_chk_result")
> Cc: <stable@vger.kernel.org> # 6.3.x
> Signed-off-by: SeongJae Park <sj@kernel.org>

Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Kefeng Wang March 6, 2023, 2:09 a.m. UTC | #2 
On 2023/3/5 3:39, SeongJae Park wrote:
> damon_pa_young() is accessing a folio via folio_size() after folio_put()
> for the folio has invoked.  Fix it.
> 

Reviewed-by: Kefeng Wang <wangkefeng.wang@huawei.com>

> Fixes: 397b0c3a584b ("mm/damon/paddr: remove folio_sz field from damon_pa_access_chk_result")
> Cc: <stable@vger.kernel.org> # 6.3.x
> Signed-off-by: SeongJae Park <sj@kernel.org>
> ---
>   mm/damon/paddr.c | 3 +--
>   1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/mm/damon/paddr.c b/mm/damon/paddr.c
> index 3fda00a0f786..10f159b315ea 100644
> --- a/mm/damon/paddr.c
> +++ b/mm/damon/paddr.c
> @@ -130,7 +130,6 @@ static bool damon_pa_young(unsigned long paddr, unsigned long *folio_sz)
>   			accessed = false;
>   		else
>   			accessed = true;
> -		folio_put(folio);
>   		goto out;
>   	}
>   
> @@ -144,10 +143,10 @@ static bool damon_pa_young(unsigned long paddr, unsigned long *folio_sz)
>   
>   	if (need_lock)
>   		folio_unlock(folio);
> -	folio_put(folio);
>   
>   out:
>   	*folio_sz = folio_size(folio);
> +	folio_put(folio);
>   	return accessed;
>   }
>
diff mbox series

Patch

diff --git a/mm/damon/paddr.c b/mm/damon/paddr.c
index 3fda00a0f786..10f159b315ea 100644
--- a/mm/damon/paddr.c
+++ b/mm/damon/paddr.c
@@ -130,7 +130,6 @@  static bool damon_pa_young(unsigned long paddr, unsigned long *folio_sz)
 			accessed = false;
 		else
 			accessed = true;
-		folio_put(folio);
 		goto out;
 	}
 
@@ -144,10 +143,10 @@  static bool damon_pa_young(unsigned long paddr, unsigned long *folio_sz)
 
 	if (need_lock)
 		folio_unlock(folio);
-	folio_put(folio);
 
 out:
 	*folio_sz = folio_size(folio);
+	folio_put(folio);
 	return accessed;
 }