diff mbox series

[2/2] mm/damon/paddr: fix folio_nr_pages() after folio_put() in damon_pa_mark_accessed_or_deactivate()

Message ID 20230304193949.296391-3-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_mark_accessed_or_deactivate() is accessing a folio via
folio_nr_pages() after folio_put() for the folio has invoked.  Fix it.

Fixes: f70da5ee8fe1 ("mm/damon: convert damon_pa_mark_accessed_or_deactivate() to use folios")
Cc: <stable@vger.kernel.org> # 6.3.x
Signed-off-by: SeongJae Park <sj@kernel.org>
---
 mm/damon/paddr.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Matthew Wilcox March 5, 2023, midnight UTC | #1 
On Sat, Mar 04, 2023 at 07:39:49PM +0000, SeongJae Park wrote:
> damon_pa_mark_accessed_or_deactivate() is accessing a folio via
> folio_nr_pages() after folio_put() for the folio has invoked.  Fix it.
> 
> Fixes: f70da5ee8fe1 ("mm/damon: convert damon_pa_mark_accessed_or_deactivate() to use folios")
> Cc: <stable@vger.kernel.org> # 6.3.x
> Signed-off-by: SeongJae Park <sj@kernel.org>

Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
diff mbox series

Patch

diff --git a/mm/damon/paddr.c b/mm/damon/paddr.c
index 10f159b315ea..0db724aec5cb 100644
--- a/mm/damon/paddr.c
+++ b/mm/damon/paddr.c
@@ -277,8 +277,8 @@  static inline unsigned long damon_pa_mark_accessed_or_deactivate(
 			folio_mark_accessed(folio);
 		else
 			folio_deactivate(folio);
-		folio_put(folio);
 		applied += folio_nr_pages(folio);
+		folio_put(folio);
 	}
 	return applied * PAGE_SIZE;
 }