From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756778AbdJKB2O (ORCPT ); Tue, 10 Oct 2017 21:28:14 -0400 Received: from mx4.wp.pl ([212.77.101.11]:21226 "EHLO mx4.wp.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751626AbdJKB2M (ORCPT ); Tue, 10 Oct 2017 21:28:12 -0400 Date: Tue, 10 Oct 2017 18:28:05 -0700 From: Jakub Kicinski To: Tyler Hicks , Kees Cook Cc: LKML Subject: BUG: KASAN: global-out-of-bounds in strscpy+0x807/0x970 Message-ID: <20171010182805.52b9b2af@cakuba.netronome.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-WP-MailID: eafec84afd5a90b4377cfd4e8ff2f4b0 X-WP-AV: skaner antywirusowy Poczty Wirtualnej Polski X-WP-SPAM: NO 000000A [4bN0] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org I'm hitting this on sysctl -a with net-next (4.14-rc4). I saw that seccomp_actions_logged_handler was introduced not-so-long-ago by Tyler, is there a fix for this? [ 753.503760] BUG: KASAN: global-out-of-bounds in strscpy+0x807/0x970 [ 753.510892] Read of size 8 at addr ffffffffa96b97c8 by task sysctl/1787 [ 753.518416] [ 753.520198] CPU: 1 PID: 1787 Comm: sysctl Not tainted 4.14.0-rc4-debug-00822-g07ec06ef312a #316 [ 753.538598] Call Trace: [ 753.541449] dump_stack+0xb3/0x140 [ 753.545372] ? _atomic_dec_and_lock+0x2b0/0x2b0 [ 753.550564] ? show_regs_print_info+0x6d/0x6d [ 753.555562] print_address_description+0x25f/0x440 [ 753.561044] ? strscpy+0x807/0x970 [ 753.564967] kasan_report+0x1b8/0x430 [ 753.569182] ? strscpy+0x807/0x970 [ 753.573107] strscpy+0x807/0x970 [ 753.576838] ? strncpy+0xf0/0xf0 [ 753.580576] ? sched_clock_cpu+0x18/0x290 [ 753.585185] seccomp_actions_logged_handler+0x384/0x8d0 [ 753.591157] ? seccomp_send_sigsys+0xa0/0xa0 [ 753.596046] ? lock_downgrade+0x740/0x740 [ 753.600648] ? get_lock_stats+0x18/0x160 [ 753.605159] ? sysctl_head_grab+0x1b/0xc0 [ 753.609766] ? lock_contended+0x1130/0x1130 [ 753.614566] ? lock_release+0x14e0/0x14e0 [ 753.619171] ? do_raw_spin_trylock+0x1c0/0x1c0 [ 753.624261] ? lock_downgrade+0x660/0x740 [ 753.628858] ? do_raw_spin_lock+0x1f0/0x1f0 [ 753.633657] proc_sys_call_handler+0x216/0x3c0 [ 753.638752] ? proc_sys_permission+0x250/0x250 [ 753.643847] ? do_mmap+0x622/0xf50 [ 753.647772] __vfs_read+0xea/0x9a0 [ 753.651696] ? vfs_copy_file_range+0xc60/0xc60 [ 753.656787] ? security_mmap_file+0x66/0x1d0 [ 753.661686] ? common_file_perm+0x1e0/0x6b0 [ 753.666485] ? vm_mmap_pgoff+0x1b6/0x250 [ 753.670993] ? fsnotify+0x1c80/0x1c80 [ 753.675209] ? apparmor_task_setrlimit+0x690/0x690 [ 753.680687] ? vma_is_stack_for_current+0xb0/0xb0 [ 753.686073] vfs_read+0x109/0x3e0 [ 753.689900] SyS_read+0xcc/0x1d0 [ 753.693628] ? kernel_write+0x1a0/0x1a0 [ 753.698034] ? trace_hardirqs_on_caller+0x3cb/0x680 [ 753.703610] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 753.708898] entry_SYSCALL_64_fastpath+0x1c/0xb1 [ 753.714180] RIP: 0033:0x7f62c82296b0 [ 753.718294] RSP: 002b:00007ffc2d6726c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 [ 753.726919] RAX: ffffffffffffffda RBX: 0000000000000046 RCX: 00007f62c82296b0 [ 753.735028] RDX: 0000000000000400 RSI: 00007f62c8722000 RDI: 0000000000000006 [ 753.743138] RBP: 0000000000000000 R08: 00000000ffffffff R09: 0000000000000000 [ 753.751246] R10: 0000000000000022 R11: 0000000000000246 R12: 0000000000000000 [ 753.759355] R13: 0000000001d63650 R14: 00007f62c87186a0 R15: 0000000000000028 [ 753.767478] [ 753.769256] The buggy address belongs to the variable: [ 753.775125] kprobes_seq_ops+0x1268/0x15c0 [ 753.779820] [ 753.781595] Memory state around the buggy address: [ 753.787075] ffffffffa96b9680: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 753.795301] ffffffffa96b9700: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 753.803526] >ffffffffa96b9780: 07 fa fa fa fa fa fa fa 00 05 fa fa fa fa fa fa [ 753.811751] ^ [ 753.818105] ffffffffa96b9800: 02 fa fa fa fa fa fa fa 00 00 04 fa fa fa fa fa [ 753.826330] ffffffffa96b9880: 00 00 00 01 fa fa fa fa 00 00 00 00 01 fa fa fa [ 753.834554] ==================================================================