+ mm-shrinkers-fix-double-kfree-on-shrinker-name-fix.patch added to mm-unstable branch

+ mm-shrinkers-fix-double-kfree-on-shrinker-name-fix.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: mm-shrinkers-fix-double-kfree-on-shrinker-name-fix
has been added to the -mm mm-unstable branch.  Its filename is
     mm-shrinkers-fix-double-kfree-on-shrinker-name-fix.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-shrinkers-fix-double-kfree-on-shrinker-name-fix.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Roman Gushchin <roman.gushchin@linux.dev>
Subject: mm-shrinkers-fix-double-kfree-on-shrinker-name-fix
Date: Wed, 20 Jul 2022 09:29:45 -0700

zero shrinker->name in all cases where shrinker->name is freed

Link: https://lkml.kernel.org/r/YtgteTnQTgyuKUSY@castle
Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/shrinker_debug.c |    1 +
 mm/vmscan.c         |    5 ++++-
 2 files changed, 5 insertions(+), 1 deletion(-)

--- a/mm/shrinker_debug.c~mm-shrinkers-fix-double-kfree-on-shrinker-name-fix
+++ a/mm/shrinker_debug.c
@@ -251,6 +251,7 @@ void shrinker_debugfs_remove(struct shri
 	lockdep_assert_held(&shrinker_rwsem);
 
 	kfree_const(shrinker->name);
+	shrinker->name = NULL;
 
 	if (!shrinker->debugfs_entry)
 		return;
--- a/mm/vmscan.c~mm-shrinkers-fix-double-kfree-on-shrinker-name-fix
+++ a/mm/vmscan.c
@@ -644,8 +644,10 @@ int prealloc_shrinker(struct shrinker *s
 		return -ENOMEM;
 
 	err = __prealloc_shrinker(shrinker);
-	if (err)
+	if (err) {
 		kfree_const(shrinker->name);
+		shrinker->name = NULL;
+	}
 
 	return err;
 }
@@ -660,6 +662,7 @@ void free_prealloced_shrinker(struct shr
 {
 #ifdef CONFIG_SHRINKER_DEBUG
 	kfree_const(shrinker->name);
+	shrinker->name = NULL;
 #endif
 	if (shrinker->flags & SHRINKER_MEMCG_AWARE) {
 		down_write(&shrinker_rwsem);
_

Patches currently in -mm which might be from roman.gushchin@linux.dev are

mm-shrinkers-fix-double-kfree-on-shrinker-name-fix.patch
mm-memcontrol-do-not-miss-memcg_max-events-for-enforced-allocations.patch