From b0cdcacd9174284d0aa411cd50b0d45d9867b09c Mon Sep 17 00:00:00 2001 From: Xu Yang Date: Wed, 6 Aug 2025 16:39:55 +0800 Subject: [PATCH] usb: core: hcd: fix accessing unmapped memory in SINGLE_STEP_SET_FEATURE test commit 8fe06185e11ae753414aa6117f0e798aa77567ff upstream. The USB core will unmap urb->transfer_dma after SETUP stage completes. Then the USB controller will access unmapped memory when it received device descriptor. If iommu is equipped, the entire test can't be completed due to the memory accessing is blocked. Fix it by calling map_urb_for_dma() again for IN stage. To reduce redundant map for urb->transfer_buffer, this will also set URB_NO_TRANSFER_DMA_MAP flag before first map_urb_for_dma() to skip dma map for urb->transfer_buffer and clear URB_NO_TRANSFER_DMA_MAP flag before second map_urb_for_dma(). Fixes: 216e0e563d81 ("usb: core: hcd: use map_urb_for_dma for single step set feature urb") Cc: stable Reviewed-by: Jun Li Signed-off-by: Xu Yang Acked-by: Alan Stern Link: https://lore.kernel.org/r/20250806083955.3325299-1-xu.yang_2@nxp.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/hcd.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c index 81e9700eeabc6..bc795257696ef 100644 --- a/drivers/usb/core/hcd.c +++ b/drivers/usb/core/hcd.c @@ -2151,7 +2151,7 @@ static struct urb *request_single_step_set_feature_urb( urb->complete = usb_ehset_completion; urb->status = -EINPROGRESS; urb->actual_length = 0; - urb->transfer_flags = URB_DIR_IN; + urb->transfer_flags = URB_DIR_IN | URB_NO_TRANSFER_DMA_MAP; usb_get_urb(urb); atomic_inc(&urb->use_count); atomic_inc(&urb->dev->urbnum); @@ -2215,9 +2215,15 @@ int ehset_single_step_set_feature(struct usb_hcd *hcd, int port) /* Complete remaining DATA and STATUS stages using the same URB */ urb->status = -EINPROGRESS; + urb->transfer_flags &= ~URB_NO_TRANSFER_DMA_MAP; usb_get_urb(urb); atomic_inc(&urb->use_count); atomic_inc(&urb->dev->urbnum); + if (map_urb_for_dma(hcd, urb, GFP_KERNEL)) { + usb_put_urb(urb); + goto out1; + } + retval = hcd->driver->submit_single_step_set_feature(hcd, urb, 0); if (!retval && !wait_for_completion_timeout(&done, msecs_to_jiffies(2000))) { -- 2.47.3