From 684a5568df11e4206a30857390e4824ac829264d Mon Sep 17 00:00:00 2001 From: Yoshihiro Shimoda Date: Thu, 18 Jun 2020 21:07:33 +0900 Subject: [PATCH] dmaengine: sh: usb-dmac: set tx_result parameters [ Upstream commit 466257d9968ac79575831250b039dc07566c7b13 ] A client driver (renesas_usbhs) assumed that dmaengine_tx_status() could return the residue even if the transfer was completed. However, this was not correct usage [1] and this caused to break getting the residue after the commit 24461d9792c2 ("dmaengine: virt-dma: Fix access after free in vchan_complete()") actually. So, this is possible to get wrong received size if the usb controller gets a short packet. For example, g_zero driver causes "bad OUT byte" errors. To use the tx_result from the renesas_usbhs driver when the transfer is completed, set the tx_result parameters. Notes that the renesas_usbhs driver needs to update for it. [1] https://lore.kernel.org/dmaengine/20200616165550.GP2324254@vkoul-mobl/ Reported-by: Hien Dang Fixes: 24461d9792c2 ("dmaengine: virt-dma: Fix access after free in vchan_complete()") Signed-off-by: Yoshihiro Shimoda Link: https://lore.kernel.org/r/1592482053-19433-1-git-send-email-yoshihiro.shimoda.uh@renesas.com Signed-off-by: Vinod Koul Signed-off-by: Sasha Levin --- drivers/dma/sh/usb-dmac.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/dma/sh/usb-dmac.c b/drivers/dma/sh/usb-dmac.c index b218a013c260..8f7ceb698226 100644 --- a/drivers/dma/sh/usb-dmac.c +++ b/drivers/dma/sh/usb-dmac.c @@ -586,6 +586,8 @@ static void usb_dmac_isr_transfer_end(struct usb_dmac_chan *chan) desc->residue = usb_dmac_get_current_residue(chan, desc, desc->sg_index - 1); desc->done_cookie = desc->vd.tx.cookie; + desc->vd.tx_result.result = DMA_TRANS_NOERROR; + desc->vd.tx_result.residue = desc->residue; vchan_cookie_complete(&desc->vd); /* Restart the next transfer if this driver has a next desc */