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 C7D47C38A02 for ; Fri, 28 Oct 2022 09:13:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230007AbiJ1JNY (ORCPT ); Fri, 28 Oct 2022 05:13:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46700 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229456AbiJ1JNW (ORCPT ); Fri, 28 Oct 2022 05:13:22 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C6E1277541; Fri, 28 Oct 2022 02:13:20 -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 ams.source.kernel.org (Postfix) with ESMTPS id 4E10BB8286D; Fri, 28 Oct 2022 09:13:19 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9CF18C433C1; Fri, 28 Oct 2022 09:13:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1666948398; bh=iYXZY4WsmuaHa1Ddq+Oh8cvkVFxpiuUetxLnBj6TjxI=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=jvhQLH+KDCqjW2so/K+XAaMCuQckB7EAlWrKywKoiXwLg5L2KXRaSV/z5UNG3sACO 4fMVJ6y/+rDUr6CHwEbAD5BJx+PBX8i5v+MgyWlx2CtDMXgCI+iE541wIIRVP32Fon 1SfjwVl88s+bEEQc4ozS50whc9OhL3P4r2lJdFuQ= Date: Fri, 28 Oct 2022 11:13:15 +0200 From: Greg KH To: Cixi Geng Cc: Thinh.Nguyen@synopsys.com, bruce.chen@unisoc.com, linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] usb: dwc3: Fix dentry leak in dwc3_gadget_free_endpoints Message-ID: References: <20221028084919.21654-1-gengcixi@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20221028084919.21654-1-gengcixi@gmail.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Oct 28, 2022 at 04:49:19PM +0800, Cixi Geng wrote: > From: Bruce Chen > > When using debugfs_remove_recursive leaks a dentry with > a hotplug stress test, the phone runs out of memory. > > Thus fix the issue by using the newly created debugfs_lookup_and_remove(). > > Signed-off-by: Bruce Chen > Signed-off-by: Cixi Geng > --- > drivers/usb/dwc3/core.h | 1 + > drivers/usb/dwc3/debugfs.c | 3 ++- > drivers/usb/dwc3/gadget.c | 4 +--- > 3 files changed, 4 insertions(+), 4 deletions(-) > > diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h > index 8f9959ba9fd4..ba3ecaa7f06c 100644 > --- a/drivers/usb/dwc3/core.h > +++ b/drivers/usb/dwc3/core.h > @@ -1261,6 +1261,7 @@ struct dwc3 { > u8 num_eps; > > struct dwc3_hwparams hwparams; > + struct dentry *root; You forgot to document this new variable. And name it a bit better? > struct debugfs_regset32 *regset; > > u32 dbg_lsp_select; > diff --git a/drivers/usb/dwc3/debugfs.c b/drivers/usb/dwc3/debugfs.c > index f2b7675c7f62..b9af4a81f51d 100644 > --- a/drivers/usb/dwc3/debugfs.c > +++ b/drivers/usb/dwc3/debugfs.c > @@ -911,6 +911,7 @@ void dwc3_debugfs_init(struct dwc3 *dwc) > dwc->regset->base = dwc->regs - DWC3_GLOBALS_REGS_START; > > root = debugfs_create_dir(dev_name(dwc->dev), usb_debug_root); > + dwc->root = root; > debugfs_create_regset32("regdump", 0444, root, dwc->regset); > debugfs_create_file("lsp_dump", 0644, root, dwc, &dwc3_lsp_fops); > > @@ -929,6 +930,6 @@ void dwc3_debugfs_init(struct dwc3 *dwc) > > void dwc3_debugfs_exit(struct dwc3 *dwc) > { > - debugfs_remove(debugfs_lookup(dev_name(dwc->dev), usb_debug_root)); > + debugfs_remove(dwc->root); > kfree(dwc->regset); > } > diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c > index 079cd333632e..6d6c188fcbea 100644 > --- a/drivers/usb/dwc3/gadget.c > +++ b/drivers/usb/dwc3/gadget.c > @@ -3172,9 +3172,7 @@ static void dwc3_gadget_free_endpoints(struct dwc3 *dwc) > list_del(&dep->endpoint.ep_list); > } > > - debugfs_remove_recursive(debugfs_lookup(dep->name, > - debugfs_lookup(dev_name(dep->dwc->dev), > - usb_debug_root))); > + debugfs_lookup_and_remove(dep->name, dwc->root); > kfree(dep); > } > } > -- > 2.34.1 > I don't think this is the full fix. Below is a patch that I've had in a tree that I need to push out (along with the other 33 debugfs_lookup patches) that should resolve this for this driver in a more complete way. Can you try this version instead? thanks, greg k-h --------------------- >From 49b893792579af1bea46c5004759cb35475c4fca Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Fri, 2 Sep 2022 16:41:39 +0200 Subject: [PATCH 06/34] USB: dwc3: debugfs_lookup() fix Signed-off-by: Greg Kroah-Hartman --- drivers/usb/dwc3/core.h | 2 ++ drivers/usb/dwc3/debug.h | 3 +++ drivers/usb/dwc3/debugfs.c | 19 ++++++++----------- drivers/usb/dwc3/gadget.c | 4 +--- 4 files changed, 14 insertions(+), 14 deletions(-) diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h index 8f9959ba9fd4..582ebd9cf9c2 100644 --- a/drivers/usb/dwc3/core.h +++ b/drivers/usb/dwc3/core.h @@ -1117,6 +1117,7 @@ struct dwc3_scratchpad_array { * address. * @num_ep_resized: carries the current number endpoints which have had its tx * fifo resized. + * @debug_root: root debugfs directory for this device to put its files in. */ struct dwc3 { struct work_struct drd_work; @@ -1332,6 +1333,7 @@ struct dwc3 { int max_cfg_eps; int last_fifo_depth; int num_ep_resized; + struct dentry *debug_root; }; #define INCRX_BURST_MODE 0 diff --git a/drivers/usb/dwc3/debug.h b/drivers/usb/dwc3/debug.h index 48b44b88dc25..8bb2c9e3b9ac 100644 --- a/drivers/usb/dwc3/debug.h +++ b/drivers/usb/dwc3/debug.h @@ -414,11 +414,14 @@ static inline const char *dwc3_gadget_generic_cmd_status_string(int status) #ifdef CONFIG_DEBUG_FS extern void dwc3_debugfs_create_endpoint_dir(struct dwc3_ep *dep); +extern void dwc3_debugfs_remove_endpoint_dir(struct dwc3_ep *dep); extern void dwc3_debugfs_init(struct dwc3 *d); extern void dwc3_debugfs_exit(struct dwc3 *d); #else static inline void dwc3_debugfs_create_endpoint_dir(struct dwc3_ep *dep) { } +static inline void dwc3_debugfs_remove_endpoint_dir(struct dwc3_ep *dep) +{ } static inline void dwc3_debugfs_init(struct dwc3 *d) { } static inline void dwc3_debugfs_exit(struct dwc3 *d) diff --git a/drivers/usb/dwc3/debugfs.c b/drivers/usb/dwc3/debugfs.c index f2b7675c7f62..850df0e6bcab 100644 --- a/drivers/usb/dwc3/debugfs.c +++ b/drivers/usb/dwc3/debugfs.c @@ -873,27 +873,23 @@ static const struct dwc3_ep_file_map dwc3_ep_file_map[] = { { "GDBGEPINFO", &dwc3_ep_info_register_fops, }, }; -static void dwc3_debugfs_create_endpoint_files(struct dwc3_ep *dep, - struct dentry *parent) +void dwc3_debugfs_create_endpoint_dir(struct dwc3_ep *dep) { + struct dentry *dir; int i; + dir = debugfs_create_dir(dep->name, dep->dwc->debug_root); for (i = 0; i < ARRAY_SIZE(dwc3_ep_file_map); i++) { const struct file_operations *fops = dwc3_ep_file_map[i].fops; const char *name = dwc3_ep_file_map[i].name; - debugfs_create_file(name, 0444, parent, dep, fops); + debugfs_create_file(name, 0444, dir, dep, fops); } } -void dwc3_debugfs_create_endpoint_dir(struct dwc3_ep *dep) +void dwc3_debugfs_remove_endpoint_dir(struct dwc3_ep *dep) { - struct dentry *dir; - struct dentry *root; - - root = debugfs_lookup(dev_name(dep->dwc->dev), usb_debug_root); - dir = debugfs_create_dir(dep->name, root); - dwc3_debugfs_create_endpoint_files(dep, dir); + debugfs_lookup_and_remove(dep->name, dep->dwc->debug_root); } void dwc3_debugfs_init(struct dwc3 *dwc) @@ -911,6 +907,7 @@ void dwc3_debugfs_init(struct dwc3 *dwc) dwc->regset->base = dwc->regs - DWC3_GLOBALS_REGS_START; root = debugfs_create_dir(dev_name(dwc->dev), usb_debug_root); + dwc->debug_root = root; debugfs_create_regset32("regdump", 0444, root, dwc->regset); debugfs_create_file("lsp_dump", 0644, root, dwc, &dwc3_lsp_fops); @@ -929,6 +926,6 @@ void dwc3_debugfs_init(struct dwc3 *dwc) void dwc3_debugfs_exit(struct dwc3 *dwc) { - debugfs_remove(debugfs_lookup(dev_name(dwc->dev), usb_debug_root)); + debugfs_lookup_and_remove(dev_name(dwc->dev), usb_debug_root); kfree(dwc->regset); } diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c index 079cd333632e..404bb7ee61a8 100644 --- a/drivers/usb/dwc3/gadget.c +++ b/drivers/usb/dwc3/gadget.c @@ -3172,9 +3172,7 @@ static void dwc3_gadget_free_endpoints(struct dwc3 *dwc) list_del(&dep->endpoint.ep_list); } - debugfs_remove_recursive(debugfs_lookup(dep->name, - debugfs_lookup(dev_name(dep->dwc->dev), - usb_debug_root))); + dwc3_debugfs_remove_endpoint_dir(dep); kfree(dep); } } -- 2.38.1