4.19-stable review patch. If anyone has any objections, please let me know.
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From: Xingxing Luo xingxing.luo@unisoc.com
commit 33d7e37232155aadebe4145dcc592f00dabd7a2b upstream.
When multiple threads are performing USB transmission, musb->lock will be unlocked when musb_giveback is executed. At this time, qh may be released in the dequeue process in other threads, resulting in a wild pointer, so it needs to be here get qh again, and judge whether qh is NULL, and when dequeue, you need to set qh to NULL.
Fixes: dbac5d07d13e ("usb: musb: host: don't start next rx urb if current one failed") Cc: stable@vger.kernel.org Signed-off-by: Xingxing Luo xingxing.luo@unisoc.com Link: https://lore.kernel.org/r/20230919033055.14085-1-xingxing.luo@unisoc.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/usb/musb/musb_host.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-)
--- a/drivers/usb/musb/musb_host.c +++ b/drivers/usb/musb/musb_host.c @@ -339,10 +339,16 @@ static void musb_advance_schedule(struct musb_giveback(musb, urb, status); qh->is_ready = ready;
+ /* + * musb->lock had been unlocked in musb_giveback, so qh may + * be freed, need to get it again + */ + qh = musb_ep_get_qh(hw_ep, is_in); + /* reclaim resources (and bandwidth) ASAP; deschedule it, and * invalidate qh as soon as list_empty(&hep->urb_list) */ - if (list_empty(&qh->hep->urb_list)) { + if (qh && list_empty(&qh->hep->urb_list)) { struct list_head *head; struct dma_controller *dma = musb->dma_controller;
@@ -2424,6 +2430,7 @@ static int musb_urb_dequeue(struct usb_h * and its URB list has emptied, recycle this qh. */ if (ready && list_empty(&qh->hep->urb_list)) { + musb_ep_set_qh(qh->hw_ep, is_in, NULL); qh->hep->hcpriv = NULL; list_del(&qh->ring); kfree(qh);