From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from fanzine2.igalia.com (fanzine2.igalia.com [213.97.179.56]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id BE24615E5AE; Fri, 2 Feb 2024 19:41:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=213.97.179.56 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706902895; cv=none; b=bX7aSQwfAiUYNjldwaPC0OG6T8pbsn+UkF2YY42nK45qvFD9z1bXSf7fZCCHCO7HGvKIY82W545/SNPzsqCUu2PqrDJ/w93cpMYfSTVxcnCBtjngyvEZOot+JVt6kwhFufN2kLj0JWhu6o5STkbFBvTy3zsNakb9SXe2YZFE70g= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706902895; c=relaxed/simple; bh=PA6V8qrjOEmRUGi+eQ/RS4oAQjuEZxBHWI8Xka+E70s=; h=Message-ID:Date:MIME-Version:In-Reply-To:To:Cc:From:Subject: Content-Type; b=NTirCzr1zhK2zFq3a9n8ICk2Tc9NXv/cWjJeqwgjMkz8NlVS1XpA5u7/6foewbJPZZ9atpKoJCqseIBsxpvRt481maRYEpwbhkYTidaqN4jz7K2xYlHQ6YU5i7ZTpGquFKm3jWjXs4c/J6uuwmJBbJ2yRfkBEV8vNfp0Qrd7mYc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=igalia.com; spf=pass smtp.mailfrom=igalia.com; dkim=pass (2048-bit key) header.d=igalia.com header.i=@igalia.com header.b=gZ6u0hYq; arc=none smtp.client-ip=213.97.179.56 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=igalia.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=igalia.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=igalia.com header.i=@igalia.com header.b="gZ6u0hYq" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=igalia.com; s=20170329; h=Content-Transfer-Encoding:Content-Type:Subject:From:Cc:To: In-Reply-To:MIME-Version:Date:Message-ID:Sender:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:References:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=PA6V8qrjOEmRUGi+eQ/RS4oAQjuEZxBHWI8Xka+E70s=; b=gZ6u0hYqRPUgVhYJbVeGYB/L9g /Ea5eM3HWDDp2WL/dJ/L2qUe77Z/CuO0U0bqKFNk9R167WtRmTjiWOCRuUarhFKJOL5lhb51L6NYI EpMlao2gZByFMHhpXgRbf6n8RspviwcY/LO6pQRwYfDRWvhCu24FkCG1TgZoTqG+pHMGlqW2Ce4KG wh2Bis9xuVCJYZulzEejI0c9KYjEF94ULju972kxSHVdFOSJ7KiNH8npvewGwr1F2l9KRtcC3qWit kdeaSO1LLofZUqQYqb3Hh+oLtti6W6CDhsHKM0FKi1TNLS3QGY9OCRmatKpL3d8h3mQKKku/YA/uE WXyhqkfQ==; Received: from [187.90.178.235] (helo=[192.168.1.60]) by fanzine2.igalia.com with esmtpsa (Cipher TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_128_GCM:128) (Exim) id 1rVzPE-00D4dK-2z; Fri, 02 Feb 2024 20:40:56 +0100 Message-ID: <66cb411b-557a-6a70-57c9-457c969fec24@igalia.com> Date: Fri, 2 Feb 2024 16:40:46 -0300 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.15.1 Content-Language: en-US In-Reply-To: <000000000000d08921060fe27342@google.com> To: syzbot+239f12e20785af44332c@syzkaller.appspotmail.com, Thomas Gleixner , jannh@google.com Cc: akpm@linux-foundation.org, Borislav Petkov , "dave.hansen@linux.intel.com" , "H. Peter Anvin" , linux-kernel , linux-mm@kvack.org, "luto@kernel.org" , Ingo Molnar , "netdev@vger.kernel.org" , Peter Zijlstra , syzkaller-bugs@googlegroups.com, "x86@kernel.org" , gpiccoli@igalia.com, "Guilherme G. Piccoli" , houtao1@huawei.com From: "Guilherme G. Piccoli" Subject: Re: [syzbot] [mm?] BUG: unable to handle kernel paging request in bpf_probe_read_compat_str Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Hi folks, I've been trying to play with this report and was able to reproduce on v6.8-rc2, in a simple qemu VM. But the thing is: after looking similar reports in MLs, this seems quite the same report as [0], so a dup. And we even have a candidate fix for it, in the form of Thomas's patch (https://lore.kernel.org/all/87r0jwquhv.ffs@tglx/). I've tested this patch and it works, preventing the crash. So... Jann: could you help me confirm the reproducer here is the same of the other report, in which you nailed it to accessing the VSYSCALL region? For me it's quite similar, but I'm not experienced in reading this kind of BPF program... Thomas: could you maybe re-submit/merge this patch, if you still agree this is the proper fix? There's a Tested-by from Hou Tao in that thread, and feel free to add mine as well! Thanks in advance and let me know if I can test more stuff / provide more data, etc - I'm glad to help here. Cheers, Guilherme [0] https://lore.kernel.org/all/000000000000c84343060a850bd0@google.com/ ("[syzbot] [mm?] BUG: unable to handle kernel paging request in copy_from_kernel_nofault")