From b20b0368c614c609badfe16fbd113dfb4780acd9 Mon Sep 17 00:00:00 2001 From: Mathieu Desnoyers Date: Thu, 30 Mar 2023 09:38:22 -0400 Subject: [PATCH] mm: fix memory leak on mm_init error handling commit f1a7941243c1 ("mm: convert mm's rss stats into percpu_counter") introduces a memory leak by missing a call to destroy_context() when a percpu_counter fails to allocate. Before introducing the per-cpu counter allocations, init_new_context() was the last call that could fail in mm_init(), and thus there was no need to ever invoke destroy_context() in the error paths. Adding the following percpu counter allocations adds error paths after init_new_context(), which means its associated destroy_context() needs to be called when percpu counters fail to allocate. Link: https://lkml.kernel.org/r/20230330133822.66271-1-mathieu.desnoyers@efficios.com Fixes: f1a7941243c1 ("mm: convert mm's rss stats into percpu_counter") Signed-off-by: Mathieu Desnoyers Acked-by: Shakeel Butt Cc: Marek Szyprowski Cc: Signed-off-by: Andrew Morton --- kernel/fork.c | 1 + 1 file changed, 1 insertion(+) diff --git a/kernel/fork.c b/kernel/fork.c index 0c92f22..ea33231 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1174,6 +1174,7 @@ static struct mm_struct *mm_init(struct mm_struct *mm, struct task_struct *p, fail_pcpu: while (i > 0) percpu_counter_destroy(&mm->rss_stat[--i]); + destroy_context(mm); fail_nocontext: mm_free_pgd(mm); fail_nopgd: -- 2.7.4