Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752913AbbHETzY (ORCPT ); Wed, 5 Aug 2015 15:55:24 -0400 Received: from mailuogwhop.emc.com ([168.159.213.141]:42645 "EHLO mailuogwhop.emc.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752007AbbHETzX (ORCPT ); Wed, 5 Aug 2015 15:55:23 -0400 X-DKIM: OpenDKIM Filter v2.4.3 mailuogwprd02.lss.emc.com t75JtJS2031050 X-DKIM: OpenDKIM Filter v2.4.3 mailuogwprd02.lss.emc.com t75JtJS2031050 From: Allen Hubbe To: Dan Williams , Dave Jiang Cc: dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org, Allen Hubbe Subject: [PATCH v2] ioatdma: fix overflow of u16 in ring_reshape Date: Wed, 5 Aug 2015 10:55:04 -0400 Message-Id: <7fb27a69349e6a5fc6006752104de90c64cb27d2.1438781843.git.Allen.Hubbe@emc.com> X-Mailer: git-send-email 2.5.0.rc1 X-RSA-Classifications: public X-Sentrion-Hostname: mailuogwprd02.lss.emc.com Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1245 Lines: 37 If the allocation order is 16, then the u16 index will overflow and wrap to zero instead of being equal or greater than 1 << 16. The loop condition will always be true, and the loop will run until all the memory resources are depleted. Change the type of index 'i' to u32, so that it is large enough to store a value equal or greater than 1 << 16. Signed-off-by: Allen Hubbe --- Version Two: rebased the fix on top of Dave Jiang's work. drivers/dma/ioat/dma.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/dma/ioat/dma.c b/drivers/dma/ioat/dma.c index a5630966834e..7435585dbbd6 100644 --- a/drivers/dma/ioat/dma.c +++ b/drivers/dma/ioat/dma.c @@ -372,7 +372,7 @@ static bool reshape_ring(struct ioatdma_chan *ioat_chan, int order) const u16 active = ioat_ring_active(ioat_chan); const u32 new_size = 1 << order; struct ioat_ring_ent **ring; - u16 i; + u32 i; if (order > ioat_get_max_alloc_order()) return false; -- 2.5.0.rc1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/