From 6c2c0204f39510b656648f12a274cbc325aa17e1 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Fri, 27 Jan 2023 14:36:27 -0800 Subject: [PATCH] dmaengine: dw-axi-dmac: Do not dereference NULL structure [ Upstream commit 91141fcd0c9c555ddc38f5b43e05c5b420d8173e ] If "vdesc" is NULL, it cannot be used with vd_to_axi_desc(). Leave "bytes" unchanged at 0. Seen under GCC 13 with -Warray-bounds: ../drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c: In function 'dma_chan_tx_status': ../drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c:329:46: warning: array subscript 0 is outside array bounds of 'struct virt_dma_desc[46116860184273879]' [-Warray-bounds=] 329 | bytes = vd_to_axi_desc(vdesc)->length; | ^~ Fixes: 98d7cbf4ddfc ("dmaengine: dw-axi-dmac: Support burst residue granularity") Cc: Eugeniy Paltsev Cc: Vinod Koul Cc: dmaengine@vger.kernel.org Signed-off-by: Kees Cook Reviewed-by: Andy Shevchenko Link: https://lore.kernel.org/r/20230127223623.never.507-kees@kernel.org Signed-off-by: Vinod Koul Signed-off-by: Sasha Levin --- drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c | 2 -- 1 file changed, 2 deletions(-) diff --git a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c index bf85aa0979ecb..152c5d98524d7 100644 --- a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c +++ b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c @@ -325,8 +325,6 @@ dma_chan_tx_status(struct dma_chan *dchan, dma_cookie_t cookie, len = vd_to_axi_desc(vdesc)->hw_desc[0].len; completed_length = completed_blocks * len; bytes = length - completed_length; - } else { - bytes = vd_to_axi_desc(vdesc)->length; } spin_unlock_irqrestore(&chan->vc.lock, flags); -- 2.39.5