USB: usblp: fix use-after-free on disconnect (7a759197) · Commits · 戴 / test

A recent commit addressing a runtime PM use-count regression, introduced a use-after-free by not making sure we held a reference to the struct usb_interface for the lifetime of the driver data. Fixes: ("USB: usblp: fix runtime PM after driver unbind") Cc: stable <stable@vger.kernel.org> Reported-by:

<syzbot+cd24df4d075c319ebfc5@syzkaller.appspotmail.com> Signed-off-by:

Johan Hovold <johan@kernel.org> Link: https://lore.kernel.org/r/20191015175522.18490-1-johan@kernel.org Signed-off-by:

Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/class/usblp.c

+3 −1

Original line number	Diff line number	Diff line
		@@ -445,6 +445,7 @@ static void usblp_cleanup(struct usblp *usblp)
		kfree(usblp->readbuf);
		kfree(usblp->device_id_string);
		kfree(usblp->statusbuf);
		usb_put_intf(usblp->intf);
		kfree(usblp);
		}

		@@ -1113,7 +1114,7 @@ static int usblp_probe(struct usb_interface *intf,
		init_waitqueue_head(&usblp->wwait);
		init_usb_anchor(&usblp->urbs);
		usblp->ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
		usblp->intf = intf;
		usblp->intf = usb_get_intf(intf);

		/* Malloc device ID string buffer to the largest expected length,
		* since we can re-query it on an ioctl and a dynamic string
		@@ -1198,6 +1199,7 @@ abort:
		kfree(usblp->readbuf);
		kfree(usblp->statusbuf);
		kfree(usblp->device_id_string);
		usb_put_intf(usblp->intf);
		kfree(usblp);
		abort_ret:
		return retval;

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