This is a note to let you know that I've just added the patch titled
xhci: Fix null pointer dereference when host dies
to the 6.1-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
xhci-fix-null-pointer-dereference-when-host-dies.patch
and it can be found in the queue-6.1 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From a2bc47c43e70cf904b1af49f76d572326c08bca7 Mon Sep 17 00:00:00 2001
From: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx>
Date: Mon, 16 Jan 2023 16:22:12 +0200
Subject: xhci: Fix null pointer dereference when host dies
From: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx>
commit a2bc47c43e70cf904b1af49f76d572326c08bca7 upstream.
Make sure xhci_free_dev() and xhci_kill_endpoint_urbs() do not race
and cause null pointer dereference when host suddenly dies.
Usb core may call xhci_free_dev() which frees the xhci->devs[slot_id]
virt device at the same time that xhci_kill_endpoint_urbs() tries to
loop through all the device's endpoints, checking if there are any
cancelled urbs left to give back.
hold the xhci spinlock while freeing the virt device
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20230116142216.1141605-4-mathias.nyman@xxxxxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/usb/host/xhci.c | 5 +++++
1 file changed, 5 insertions(+)
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -3974,6 +3974,7 @@ static void xhci_free_dev(struct usb_hcd
struct xhci_hcd *xhci = hcd_to_xhci(hcd);
struct xhci_virt_device *virt_dev;
struct xhci_slot_ctx *slot_ctx;
+ unsigned long flags;
int i, ret;
/*
@@ -4000,7 +4001,11 @@ static void xhci_free_dev(struct usb_hcd
virt_dev->eps[i].ep_state &= ~EP_STOP_CMD_PENDING;
virt_dev->udev = NULL;
xhci_disable_slot(xhci, udev->slot_id);
+
+ spin_lock_irqsave(&xhci->lock, flags);
xhci_free_virt_device(xhci, udev->slot_id);
+ spin_unlock_irqrestore(&xhci->lock, flags);
+
}
int xhci_disable_slot(struct xhci_hcd *xhci, u32 slot_id)
Patches currently in stable-queue which might be from mathias.nyman@xxxxxxxxxxxxxxx are
queue-6.1/usb-acpi-add-helper-to-check-port-lpm-capability-using-acpi-_dsm.patch
queue-6.1/xhci-fix-null-pointer-dereference-when-host-dies.patch
queue-6.1/xhci-pci-set-the-dma-max_seg_size.patch
queue-6.1/usb-xhci-check-endpoint-is-valid-before-dereferencing-it.patch
queue-6.1/xhci-add-update_hub_device-override-for-pci-xhci-hosts.patch
queue-6.1/xhci-detect-lpm-incapable-xhc-usb3-roothub-ports-from-acpi-tables.patch
queue-6.1/xhci-add-a-flag-to-disable-usb3-lpm-on-a-xhci-root-port-level.patch
