From: Mathieu Desnoyers mathieu.desnoyers@efficios.com
commit b20b0368c614c609badfe16fbd113dfb4780acd9 upstream.
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.... Fixes: f1a7941243c1 ("mm: convert mm's rss stats into percpu_counter") Signed-off-by: Mathieu Desnoyers mathieu.desnoyers@efficios.com Acked-by: Shakeel Butt shakeelb@google.com Cc: Marek Szyprowski m.szyprowski@samsung.com Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- kernel/fork.c | 1 + 1 file changed, 1 insertion(+)
--- a/kernel/fork.c +++ b/kernel/fork.c @@ -1177,6 +1177,7 @@ static struct mm_struct *mm_init(struct fail_pcpu: while (i > 0) percpu_counter_destroy(&mm->rss_stat[--i]); + destroy_context(mm); fail_nocontext: mm_free_pgd(mm); fail_nopgd: