From 90b5a54c4ccb33799f1cd4d3de37761d55646ea4 Mon Sep 17 00:00:00 2001 From: Roman Gushchin Date: Wed, 20 Jul 2022 09:29:45 -0700 Subject: [PATCH] mm-shrinkers-fix-double-kfree-on-shrinker-name-fix zero shrinker->name in all cases where shrinker->name is freed Link: https://lkml.kernel.org/r/YtgteTnQTgyuKUSY@castle Cc: Tetsuo Handa Signed-off-by: Andrew Morton --- mm/shrinker_debug.c | 1 + mm/vmscan.c | 5 ++++- 2 files changed, 5 insertions(+), 1 deletion(-) diff --git a/mm/shrinker_debug.c b/mm/shrinker_debug.c index e5b40c43221d..b05295bab322 100644 --- a/mm/shrinker_debug.c +++ b/mm/shrinker_debug.c @@ -251,6 +251,7 @@ void shrinker_debugfs_remove(struct shrinker *shrinker) lockdep_assert_held(&shrinker_rwsem); kfree_const(shrinker->name); + shrinker->name = NULL; if (!shrinker->debugfs_entry) return; diff --git a/mm/vmscan.c b/mm/vmscan.c index f8d97b905f21..fbb4108250ee 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -644,8 +644,10 @@ int prealloc_shrinker(struct shrinker *shrinker, const char *fmt, ...) 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 shrinker *shrinker) { #ifdef CONFIG_SHRINKER_DEBUG kfree_const(shrinker->name); + shrinker->name = NULL; #endif if (shrinker->flags & SHRINKER_MEMCG_AWARE) { down_write(&shrinker_rwsem); -- 2.50.1