Commit 44d7175d authored Sep 08, 2015 by Sergey Senozhatsky Committed by Linus Torvalds Sep 08, 2015

mm/dmapool: allow NULL `pool' pointer in dma_pool_destroy()

dma_pool_destroy() does not tolerate a NULL dma_pool pointer argument and
performs a NULL-pointer dereference.  This requires additional attention
and effort from developers/reviewers and forces all dma_pool_destroy()
callers to do a NULL check

    if (pool)
        dma_pool_destroy(pool);

Or, otherwise, be invalid dma_pool_destroy() users.

Tweak dma_pool_destroy() and NULL-check the pointer there.

Proposed by Andrew Morton.

Link: https://lkml.org/lkml/2015/6/8/583


Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Julia Lawall <julia.lawall@lip6.fr>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 4e3ca3e0

mm/dmapool.c

+3 −0

Original line number	Diff line number	Diff line
		@@ -271,6 +271,9 @@ void dma_pool_destroy(struct dma_pool *pool)
		{
		bool empty = false;

		if (unlikely(!pool))
		return;

		mutex_lock(&pools_reg_lock);
		mutex_lock(&pools_lock);
		list_del(&pool->pools);

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