On Thu, Aug 19, 2021 at 11:56:59AM +0000, Chunfeng Yun (云春峰) wrote:

Hi Greg,

On Thu, 2021-08-05 at 13:37 +0800, Ikjoon Jang wrote:

quoted

xhci-mtk depends on xhci's internal virt_dev when it retrieves its
internal data from usb_host_endpoint both in add_endpoint and
drop_endpoint callbacks. But when setup packet was retired by
transaction errors in xhci_setup_device() path, a virt_dev for the
slot
is newly created with real_port 0. This leads to xhci-mtks's NULL
pointer
dereference from drop_endpoint callback as xhci-mtk assumes that
virt_dev's
real_port is always started from one. The similar problems were
addressed
by [1] but that can't cover the failure cases from setup_device.

This patch drops the usages of xhci's virt_dev in xhci-mtk's
drop_endpoint
callback by adopting rhashtable for searching mtk's schedule entity
from a given usb_host_endpoint pointer instead of searching a linked
list.
So mtk's drop_endpoint callback doesn't have to rely on virt_dev at
all.

[1] 
https://lore.kernel.org/r/1617179142-2681-2-git-send-email-chunfeng.yun@mediatek.com (local)

Signed-off-by: Ikjoon Jang <redacted>
---

 drivers/usb/host/xhci-mtk-sch.c | 140 ++++++++++++++++++----------
----
 drivers/usb/host/xhci-mtk.h     |  15 ++--
 2 files changed, 86 insertions(+), 69 deletions(-)

diff --git a/drivers/usb/host/xhci-mtk-sch.c b/drivers/usb/host/xhci-

mtk-sch.c
index cffcaf4dfa9f..f9b4d27ce449 100644

--- a/drivers/usb/host/xhci-mtk-sch.c
+++ b/drivers/usb/host/xhci-mtk-sch.c

I see the patch is already in usb-next branch, but find some new bugs
introduced after I test it (one NULL point dereference oops, two memory
leakage due to no error handling). 
What do I need to do? revert this patch then send new version or just
send fix patches?

Which ever you want to do is fine with me.

thanks,

greg k-h