mm: fix memory leak on mm_init error handling

commit f1a7941243 ("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: f1a7941243 ("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>

This commit is contained in:

Mathieu Desnoyers

2023-03-30 09:38:22 -04:00

committed by

Andrew Morton

parent 1007843a91

commit b20b0368c6

1 changed files with 1 additions and 0 deletions

									
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kernel/fork.c

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				@ -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:

mm: fix memory leak on mm_init error handling

1 kernel/fork.c Unescape Escape View File

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kernel/fork.c

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