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.
Signed-off-by: Mathieu Desnoyers mathieu.desnoyers@efficios.com Cc: Shakeel Butt shakeelb@google.com Cc: Andrew Morton akpm@linux-foundation.org Cc: Marek Szyprowski m.szyprowski@samsung.com Cc: linux-mm@kvack.org Cc: stable@vger.kernel.org # 6.2 --- kernel/fork.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/kernel/fork.c b/kernel/fork.c index c0257cbee093..c983c4fe3090 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1171,6 +1171,7 @@ 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: