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 X-Spam-Level: X-Spam-Status: No, score=-10.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id DB034C2D0E0 for ; Tue, 15 Sep 2020 05:26:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A87802078D for ; Tue, 15 Sep 2020 05:26:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600147609; bh=3YRNdYIm4sAf3BLgQjBz79qzM15AHtoJPCq5PN9ukyQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=WZlHNQGHq/1Vk2L3F5WMBX5NQZdxDPojrXA6oWgaPJds/XlKqtS9aayQ4TwTj1192 U8X7HKFADKf1wXPyuSuoEBJDOh8nli4pshWaskg0Q6Zo2epqjflQDXWhd41ImD3XRq bCYiWj97RDEpkRrU2gl4fjplk3YctND9M0GtL0L4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726146AbgIOF0p (ORCPT ); Tue, 15 Sep 2020 01:26:45 -0400 Received: from mail.kernel.org ([198.145.29.99]:56276 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726057AbgIOF0p (ORCPT ); Tue, 15 Sep 2020 01:26:45 -0400 Received: from sol.localdomain (172-10-235-113.lightspeed.sntcca.sbcglobal.net [172.10.235.113]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 4320C20756; Tue, 15 Sep 2020 05:26:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600147604; bh=3YRNdYIm4sAf3BLgQjBz79qzM15AHtoJPCq5PN9ukyQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=zuMEpouuEr8pt08h+xo1UWS3YJw43raWeTOxfgZvC72zPFpYl70NRSDSuToU2Aecw X/ofVOJe662gdkbA2w8+rjyoemD2RHFUoyKTjYBbwCPVC2NiX9BqjTCM09AI7r4xkk JZUwj2AgpmKt4RTu/lraKqhKBfczLVvVeZcWYQYI= Date: Mon, 14 Sep 2020 22:26:42 -0700 From: Eric Biggers To: Anmol Karn Cc: Matthew Wilcox , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kernel-mentees@lists.linuxfoundation.org, syzbot+f7204dcf3df4bb4ce42c@syzkaller.appspotmail.com, Eric Dumazet , Bjorn Andersson , Manivannan Sadhasivam , Jakub Kicinski , "David S. Miller" , netdev , Necip Fazil Yildiran Subject: Re: [PATCH] idr: remove WARN_ON_ONCE() when trying to check id Message-ID: <20200915052642.GO899@sol.localdomain> References: <20200914071724.202365-1-anmol.karan123@gmail.com> <20200914110803.GL6583@casper.infradead.org> <20200914184755.GB213347@Thinkpad> <20200914192655.GW6583@casper.infradead.org> <20200915051331.GA7980@Thinkpad> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200915051331.GA7980@Thinkpad> Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Tue, Sep 15, 2020 at 10:43:31AM +0530, Anmol Karn wrote: > On Mon, Sep 14, 2020 at 08:26:55PM +0100, Matthew Wilcox wrote: > > On Tue, Sep 15, 2020 at 12:17:55AM +0530, Anmol Karn wrote: > > > On Mon, Sep 14, 2020 at 12:08:03PM +0100, Matthew Wilcox wrote: > > > > On Mon, Sep 14, 2020 at 12:47:24PM +0530, Anmol Karn wrote: > > > > > idr_get_next() gives WARN_ON_ONCE() when it gets (id > INT_MAX) true > > > > > and this happens when syzbot does fuzzing, and that warning is > > > > > expected, but WARN_ON_ONCE() is not required here and, cecking > > > > > the condition and returning NULL value would be suffice. > > > > > > > > > > Reference: commit b9959c7a347 ("filldir[64]: remove WARN_ON_ONCE() for bad directory entries") > > > > > Reported-and-tested-by: syzbot+f7204dcf3df4bb4ce42c@syzkaller.appspotmail.com > > > > > Link: https://syzkaller.appspot.com/bug?extid=f7204dcf3df4bb4ce42c > > > > > Signed-off-by: Anmol Karn > > > > > > > > https://lore.kernel.org/netdev/20200605120037.17427-1-willy@infradead.org/ > > > > > > Hello sir, > > > > > > I have looked into the patch, and it seems the problem is fixed to the root cause > > > in this patch, but not yet merged due to some backport issues, so, please ignore > > > this patch(sent by me), and please let me know if i can contribute to fixing this > > > bug's root cause. > > > > The root cause is that the network maintainers believe I have a far > > greater interest in the qrtr code than I actually do, and the maintainer > > of the qrtr code is not doing anything. > > Hello sir, > > I hope the patch will get merged soon. No need to "hope"; you could split up Matthew's patch yourself, and test and send the resulting patches. From the above thread, it looks like the networking developers want one patch to fix the improper use of GFP_ATOMIC (which is the bug reported by syzbot), and a separate patch to convert qrtr to use the XArray. > also, i have tried a patch for this bug > > Link: https://syzkaller.appspot.com/bug?extid=3b14b2ed9b3d06dcaa07 > > can you please guide me little how should i proceede with it, and > also syzbot tested it. Looks like something timer-related. You'll need to investigate more, write and test a fix, and send it to the appropriate kernel mailing lists and developers (which will probably be different from the ones receiving this current thread). - Eric