From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5EAAFC43334 for ; Tue, 7 Jun 2022 19:43:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1356235AbiFGTnE (ORCPT ); Tue, 7 Jun 2022 15:43:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58034 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1354538AbiFGSrH (ORCPT ); Tue, 7 Jun 2022 14:47:07 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2AAB7AFB3F; Tue, 7 Jun 2022 11:02:00 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id BA1F2617AE; Tue, 7 Jun 2022 18:01:59 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 38906C3411F; Tue, 7 Jun 2022 18:01:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1654624919; bh=ahCWFjMh8WyDj8Acc6WZ3lx9b4o/NO9n4MoAfv21HLg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=S2o0NVzzyrsnAQgCiCaoXBM+u8sObWfm6jhi7UwixHifHuNeTQ6xON0mAackFopPX etqMes9PdKbG5ho+tnqi1jHxj8A9rtx9dGE5+A0yNbrl/LoCvUAL8MjTyjkSNA8cWG UesRPwyvelyp61RyJ0o2iEvJAmoH2fj5JeKsjKYRBJ4FibOvvAj+f6NMLAFnEOyYeg NG91GwdVTnSTljmZwCeMp18ZDAgrWQcTDvhwVwL7NVpamP+NyyYLVPHldDsndClROl nrjB8e/bUf/DwuhD0UrUnAZC1qSMJsiHC/1Pq9PhgX2saIE02M4xzFEVysSPH2aBnX X9QuGslPgv2Pg== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Marek Szyprowski , Greg Kroah-Hartman , Sasha Levin , hminas@synopsys.com, linux-usb@vger.kernel.org Subject: [PATCH AUTOSEL 4.19 11/27] usb: dwc2: gadget: don't reset gadget's driver->bus Date: Tue, 7 Jun 2022 14:01:15 -0400 Message-Id: <20220607180133.481701-11-sashal@kernel.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220607180133.481701-1-sashal@kernel.org> References: <20220607180133.481701-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Marek Szyprowski [ Upstream commit 3120aac6d0ecd9accf56894aeac0e265f74d3d5a ] UDC driver should not touch gadget's driver internals, especially it should not reset driver->bus. This wasn't harmful so far, but since commit fc274c1e9973 ("USB: gadget: Add a new bus for gadgets") gadget subsystem got it's own bus and messing with ->bus triggers the following NULL pointer dereference: dwc2 12480000.hsotg: bound driver g_ether 8<--- cut here --- Unable to handle kernel NULL pointer dereference at virtual address 00000000 [00000000] *pgd=00000000 Internal error: Oops: 5 [#1] SMP ARM Modules linked in: ... CPU: 0 PID: 620 Comm: modprobe Not tainted 5.18.0-rc5-next-20220504 #11862 Hardware name: Samsung Exynos (Flattened Device Tree) PC is at module_add_driver+0x44/0xe8 LR is at sysfs_do_create_link_sd+0x84/0xe0 ... Process modprobe (pid: 620, stack limit = 0x(ptrval)) ... module_add_driver from bus_add_driver+0xf4/0x1e4 bus_add_driver from driver_register+0x78/0x10c driver_register from usb_gadget_register_driver_owner+0x40/0xb4 usb_gadget_register_driver_owner from do_one_initcall+0x44/0x1e0 do_one_initcall from do_init_module+0x44/0x1c8 do_init_module from load_module+0x19b8/0x1b9c load_module from sys_finit_module+0xdc/0xfc sys_finit_module from ret_fast_syscall+0x0/0x54 Exception stack(0xf1771fa8 to 0xf1771ff0) ... dwc2 12480000.hsotg: new device is high-speed ---[ end trace 0000000000000000 ]--- Fix this by removing driver->bus entry reset. Signed-off-by: Marek Szyprowski Link: https://lore.kernel.org/r/20220505104618.22729-1-m.szyprowski@samsung.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/usb/dwc2/gadget.c | 1 - 1 file changed, 1 deletion(-) diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c index 1e46005929e4..85d25f7e9c27 100644 --- a/drivers/usb/dwc2/gadget.c +++ b/drivers/usb/dwc2/gadget.c @@ -4326,7 +4326,6 @@ static int dwc2_hsotg_udc_start(struct usb_gadget *gadget, WARN_ON(hsotg->driver); - driver->driver.bus = NULL; hsotg->driver = driver; hsotg->gadget.dev.of_node = hsotg->dev->of_node; hsotg->gadget.speed = USB_SPEED_UNKNOWN; -- 2.35.1