From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751384AbdEBQqL (ORCPT ); Tue, 2 May 2017 12:46:11 -0400 Received: from mail-yw0-f182.google.com ([209.85.161.182]:32776 "EHLO mail-yw0-f182.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750770AbdEBQqJ (ORCPT ); Tue, 2 May 2017 12:46:09 -0400 MIME-Version: 1.0 In-Reply-To: References: From: Andrey Konovalov Date: Tue, 2 May 2017 18:46:07 +0200 Message-ID: Subject: Re: net/key: slab-out-of-bounds in pfkey_compile_policy To: Steffen Klassert , Herbert Xu , "David S. Miller" , netdev , LKML Cc: Dmitry Vyukov , Kostya Serebryany , Eric Dumazet , Cong Wang , syzkaller Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, May 2, 2017 at 6:45 PM, Andrey Konovalov wrote: > Hi, > > I've got the following error report while fuzzing the kernel with syzkaller. > > On commit d3b5d35290d729a2518af00feca867385a1b08fa (4.11). > > A reproducer and .config are attached. > > ================================================================== > BUG: KASAN: slab-out-of-bounds in pfkey_compile_policy+0x8e6/0xd40 at > addr ffff88006701f798 > Read of size 1280 by task a.out/4181 > CPU: 0 PID: 4181 Comm: a.out Not tainted 4.11.0+ #306 > Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 > Call Trace: > __dump_stack lib/dump_stack.c:16 > dump_stack+0x292/0x395 lib/dump_stack.c:52 > kasan_object_err+0x1c/0x70 mm/kasan/report.c:164 > print_address_description mm/kasan/report.c:202 > kasan_report_error mm/kasan/report.c:291 > kasan_report+0x252/0x510 mm/kasan/report.c:347 > check_memory_region_inline mm/kasan/kasan.c:326 > check_memory_region+0x139/0x190 mm/kasan/kasan.c:333 > memcpy+0x23/0x50 mm/kasan/kasan.c:368 > pfkey_sadb2xfrm_user_sec_ctx net/key/af_key.c:474 > pfkey_compile_policy+0x8e6/0xd40 net/key/af_key.c:3294 > xfrm_user_policy+0x349/0x560 net/xfrm/xfrm_state.c:1892 > do_ip_setsockopt.isra.12+0x1d05/0x38c0 net/ipv4/ip_sockglue.c:1175 > ip_setsockopt+0x3a/0xb0 net/ipv4/ip_sockglue.c:1264 > tcp_setsockopt+0x82/0xd0 net/ipv4/tcp.c:2732 > sock_common_setsockopt+0x95/0xd0 net/core/sock.c:2750 > SYSC_setsockopt net/socket.c:1798 > SyS_setsockopt+0x270/0x3a0 net/socket.c:1777 > entry_SYSCALL_64_fastpath+0x1f/0xbe arch/x86/entry/entry_64.S:204 > RIP: 0033:0x7f13a0968b79 > RSP: 002b:00007fff131bc3f8 EFLAGS: 00000206 ORIG_RAX: 0000000000000036 > RAX: ffffffffffffffda RBX: 00007fff131bc550 RCX: 00007f13a0968b79 > RDX: 0000000000000010 RSI: 0000000000000000 RDI: 0000000000000003 > RBP: 00000000004004e0 R08: 00000000000000c2 R09: 0000000000000000 > R10: 0000000020a2ff3e R11: 0000000000000206 R12: 0000000000000000 > R13: 00007fff131bc550 R14: 0000000000000000 R15: 0000000000000000 > Object at ffff88006701f780, in cache kmalloc-256 size: 256 > Allocated: > PID = 4181 > save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 > save_stack+0x43/0xd0 mm/kasan/kasan.c:513 > set_track mm/kasan/kasan.c:525 > kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:616 > __kmalloc+0xa0/0x2d0 mm/slub.c:3745 > kmalloc ./include/linux/slab.h:495 > xfrm_user_policy+0xd8/0x560 net/xfrm/xfrm_state.c:1881 > do_ip_setsockopt.isra.12+0x1d05/0x38c0 net/ipv4/ip_sockglue.c:1175 > ip_setsockopt+0x3a/0xb0 net/ipv4/ip_sockglue.c:1264 > tcp_setsockopt+0x82/0xd0 net/ipv4/tcp.c:2732 > sock_common_setsockopt+0x95/0xd0 net/core/sock.c:2750 > SYSC_setsockopt net/socket.c:1798 > SyS_setsockopt+0x270/0x3a0 net/socket.c:1777 > entry_SYSCALL_64_fastpath+0x1f/0xbe arch/x86/entry/entry_64.S:204 > Freed: > PID = 3951 > save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 > save_stack+0x43/0xd0 mm/kasan/kasan.c:513 > set_track mm/kasan/kasan.c:525 > kasan_slab_free+0x73/0xc0 mm/kasan/kasan.c:589 > slab_free_hook mm/slub.c:1357 > slab_free_freelist_hook mm/slub.c:1379 > slab_free mm/slub.c:2961 > kfree+0xe8/0x2b0 mm/slub.c:3882 > free_bprm+0x19d/0x200 fs/exec.c:1382 > do_execveat_common.isra.34+0x19ad/0x2220 fs/exec.c:1778 > do_execve fs/exec.c:1813 > SYSC_execve fs/exec.c:1894 > SyS_execve+0x39/0x50 fs/exec.c:1889 > do_syscall_64+0x2c7/0x7a0 arch/x86/entry/common.c:281 > return_from_SYSCALL_64+0x0/0x7a arch/x86/entry/entry_64.S:246 > Memory state around the buggy address: > ffff88006701f700: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc > ffff88006701f780: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >>ffff88006701f800: 00 00 00 00 00 00 00 00 02 fc fc fc fc fc fc fc > ^ > ffff88006701f880: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb > ffff88006701f900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ================================================================== + syzkaller