From mboxrd@z Thu Jan 1 00:00:00 1970 From: bugzilla-daemon@bugzilla.kernel.org Subject: [Bug 202883] sometime dead lock in getdents64 Date: Tue, 12 Mar 2019 06:53:05 +0000 Message-ID: References: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from [172.30.20.202] (helo=mx.sourceforge.net) by sfs-ml-1.v29.lw.sourceforge.com with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.90_1) (envelope-from ) id 1h3bHl-00080S-Eu for linux-f2fs-devel@lists.sourceforge.net; Tue, 12 Mar 2019 06:53:13 +0000 Received: from mail.wl.linuxfoundation.org ([198.145.29.98]) by sfi-mx-1.v28.lw.sourceforge.com with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.90_1) id 1h3bHj-005QG0-JS for linux-f2fs-devel@lists.sourceforge.net; Tue, 12 Mar 2019 06:53:13 +0000 Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id EBB832945F for ; Tue, 12 Mar 2019 06:53:05 +0000 (UTC) In-Reply-To: List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: linux-f2fs-devel-bounces@lists.sourceforge.net To: linux-f2fs-devel@lists.sourceforge.net https://bugzilla.kernel.org/show_bug.cgi?id=202883 --- Comment #1 from Jiqun Li (jiqun.li@unisoc.com) --- for task 9709, do_page_fault() is triggered by __put_user_unaligned() in compat_filldir64(). static int compat_filldir64(struct dir_context *ctx, const char *name, int namlen, loff_t offset, u64 ino, unsigned int d_type) { ..... if (dirent) { if (__put_user_unaligned(offset, &dirent->d_off)) goto efault; } dirent is a local array[] in user space, when want to access dirent->d_off, do_page_fault() is triggered and want to alloc real memory. dirent is a valid user space address -- You are receiving this mail because: You are watching the assignee of the bug.