From mboxrd@z Thu Jan 1 00:00:00 1970 From: mporter@ti.com (Matt Porter) Date: Tue, 5 Mar 2013 10:58:22 -0500 Subject: [PATCH v2] arm: davinci: fix edma dmaengine induced null pointer dereference on da830 Message-ID: <1362499102-16468-1-git-send-email-mporter@ti.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org This adds additional error checking to the private edma api implementation to catch the case where the edma_alloc_slot() has an invalid controller parameter. The edma dmaengine wrapper driver relies on this condition being handled in order to avoid setting up a second edma dmaengine instance on DA830. Verfied using a DA850 with the second EDMA controller platform instance removed to simulate a DA830 which only has a single EDMA controller. Reported-by: Tomas Novotny Signed-off-by: Matt Porter Cc: stable at vger.kernel.org # v3.7.x+ --- v2: Move error check out of conditional to catch all cases arch/arm/mach-davinci/dma.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/arm/mach-davinci/dma.c b/arch/arm/mach-davinci/dma.c index a685e97..45b7c71 100644 --- a/arch/arm/mach-davinci/dma.c +++ b/arch/arm/mach-davinci/dma.c @@ -743,6 +743,9 @@ EXPORT_SYMBOL(edma_free_channel); */ int edma_alloc_slot(unsigned ctlr, int slot) { + if (!edma_cc[ctlr]) + return -EINVAL; + if (slot >= 0) slot = EDMA_CHAN_SLOT(slot); -- 1.7.9.5