The patch titled Subject: mm: fix memory leak on mm_init error handling has been added to the -mm mm-hotfixes-unstable branch. Its filename is mm-fix-memory-leak-on-mm_init-error-handling.patch

This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches...

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

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------------------------------------------------------ From: Mathieu Desnoyers mathieu.desnoyers@efficios.com Subject: mm: fix memory leak on mm_init error handling Date: Thu, 30 Mar 2023 09:38:22 -0400

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 ---

kernel/fork.c | 1 + 1 file changed, 1 insertion(+)

--- a/kernel/fork.c~mm-fix-memory-leak-on-mm_init-error-handling +++ a/kernel/fork.c @@ -1174,6 +1174,7 @@ 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: _

Patches currently in -mm which might be from mathieu.desnoyers@efficios.com are

mm-fix-memory-leak-on-mm_init-error-handling.patch