From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail78-36.sinamail.sina.com.cn (mail78-36.sinamail.sina.com.cn [219.142.78.36]) (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 B777D4419 for ; Sat, 30 Dec 2023 01:27:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=sina.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=sina.com X-SMAIL-HELO: localhost.localdomain Received: from unknown (HELO localhost.localdomain)([113.88.48.29]) by sina.com (172.16.235.25) with ESMTP id 658F71ED00003E78; Sat, 30 Dec 2023 09:27:12 +0800 (CST) X-Sender: hdanton@sina.com X-Auth-ID: hdanton@sina.com Authentication-Results: sina.com; spf=none smtp.mailfrom=hdanton@sina.com; dkim=none header.i=none; dmarc=none action=none header.from=hdanton@sina.com X-SMAIL-MID: 0784034210107 X-SMAIL-UIID: 8235E027289949999FF295CE4876E4BB-20231230-092712-1 From: Hillf Danton To: syzbot Cc: linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Subject: Re: [syzbot] [fs?] BUG: unable to handle kernel paging request in mmu_notifier_invalidate_range_start Date: Sat, 30 Dec 2023 09:26:59 +0800 Message-Id: <20231230012659.2135-1-hdanton@sina.com> In-Reply-To: <0000000000001c6fbf060dab4271@google.com> References: <0000000000001c6fbf060dab4271@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit On Fri, 29 Dec 2023 11:44:19 -0800 > HEAD commit: aafe7ad77b91 Merge branch 'for-next/core' into for-kernelci > git tree: git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=12ef73d6e80000 #syz test https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master --- x/fs/proc/task_mmu.c +++ y/fs/proc/task_mmu.c @@ -2491,8 +2491,9 @@ static long do_pagemap_cmd(struct file * switch (cmd) { case PAGEMAP_SCAN: - return do_pagemap_scan(mm, arg); - + if (mm) + return do_pagemap_scan(mm, arg); + /* fall thru */ default: return -EINVAL; } --