From mboxrd@z Thu Jan 1 00:00:00 1970 From: syzbot Subject: KASAN: use-after-free Read in tipc_group_cong Date: Wed, 12 Dec 2018 03:11:04 -0800 Message-ID: <0000000000000dbf4a057cd1418b@google.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8"; format=flowed; delsp=yes To: davem@davemloft.net, jon.maloy@ericsson.com, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, syzkaller-bugs@googlegroups.com, tipc-discussion@lists.sourceforge.net, ying.xue@windriver.com Return-path: Received: from mail-io1-f72.google.com ([209.85.166.72]:37715 "EHLO mail-io1-f72.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727061AbeLLLLG (ORCPT ); Wed, 12 Dec 2018 06:11:06 -0500 Received: by mail-io1-f72.google.com with SMTP id d63so16986526iog.4 for ; Wed, 12 Dec 2018 03:11:05 -0800 (PST) Sender: netdev-owner@vger.kernel.org List-ID: Hello, syzbot found the following crash on: HEAD commit: f5d582777bcb Merge branch 'for-linus' of git://git.kernel... git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=1705d525400000 kernel config: https://syzkaller.appspot.com/x/.config?x=c8970c89a0efbb23 dashboard link: https://syzkaller.appspot.com/bug?extid=9845fed98688e01f431e compiler: gcc (GCC) 8.0.1 20180413 (experimental) syz repro: https://syzkaller.appspot.com/x/repro.syz?x=101b6ba3400000 IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+9845fed98688e01f431e@syzkaller.appspotmail.com 8021q: adding VLAN 0 to HW filter on device team0 8021q: adding VLAN 0 to HW filter on device team0 audit: type=1400 audit(1544592509.246:38): avc: denied { associate } for pid=6204 comm="syz-executor5" name="syz5" scontext=unconfined_u:object_r:unlabeled_t:s0 tcontext=system_u:object_r:unlabeled_t:s0 tclass=filesystem permissive=1 ================================================================== BUG: KASAN: use-after-free in tipc_group_find_dest net/tipc/group.c:255 [inline] BUG: KASAN: use-after-free in tipc_group_cong+0x566/0x5d0 net/tipc/group.c:416 Read of size 8 at addr ffff8881c59f5000 by task syz-executor4/10565 CPU: 1 PID: 10565 Comm: syz-executor4 Not tainted 4.20.0-rc6+ #151 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x244/0x39d lib/dump_stack.c:113 print_address_description.cold.7+0x9/0x1ff mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.8+0x242/0x309 mm/kasan/report.c:412 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433 tipc_group_find_dest net/tipc/group.c:255 [inline] tipc_group_cong+0x566/0x5d0 net/tipc/group.c:416 tipc_send_group_anycast+0x9bb/0xc80 net/tipc/socket.c:972 __tipc_sendmsg+0x12b1/0x1d40 net/tipc/socket.c:1309 tipc_sendmsg+0x50/0x70 net/tipc/socket.c:1272 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg+0xd5/0x120 net/socket.c:631 ___sys_sendmsg+0x7fd/0x930 net/socket.c:2116 __sys_sendmsg+0x11d/0x280 net/socket.c:2154 __do_sys_sendmsg net/socket.c:2163 [inline] __se_sys_sendmsg net/socket.c:2161 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2161 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457679 Code: fd b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 cb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f813d748c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457679 RDX: 0000000000000000 RSI: 00000000200006c0 RDI: 0000000000000005 RBP: 000000000072bfa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f813d7496d4 R13: 00000000004c44dd R14: 00000000004d74c8 R15: 00000000ffffffff Allocated by task 10551: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0xc7/0xe0 mm/kasan/kasan.c:553 kmem_cache_alloc_trace+0x152/0x750 mm/slab.c:3620 kmalloc include/linux/slab.h:546 [inline] kzalloc include/linux/slab.h:741 [inline] tipc_group_create+0x152/0xa70 net/tipc/group.c:171 tipc_sk_join net/tipc/socket.c:2829 [inline] tipc_setsockopt+0x2d1/0xd70 net/tipc/socket.c:2944 __sys_setsockopt+0x1ba/0x3c0 net/socket.c:1902 __do_sys_setsockopt net/socket.c:1913 [inline] __se_sys_setsockopt net/socket.c:1910 [inline] __x64_sys_setsockopt+0xbe/0x150 net/socket.c:1910 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 10567: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/kasan.c:521 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 __cache_free mm/slab.c:3498 [inline] kfree+0xcf/0x230 mm/slab.c:3817 tipc_group_delete+0x2e4/0x3f0 net/tipc/group.c:227 tipc_sk_leave+0x113/0x220 net/tipc/socket.c:2863 tipc_setsockopt+0x97d/0xd70 net/tipc/socket.c:2947 __sys_setsockopt+0x1ba/0x3c0 net/socket.c:1902 __do_sys_setsockopt net/socket.c:1913 [inline] __se_sys_setsockopt net/socket.c:1910 [inline] __x64_sys_setsockopt+0xbe/0x150 net/socket.c:1910 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff8881c59f5000 which belongs to the cache kmalloc-192 of size 192 The buggy address is located 0 bytes inside of 192-byte region [ffff8881c59f5000, ffff8881c59f50c0) The buggy address belongs to the page: page:ffffea0007167d40 count:1 mapcount:0 mapping:ffff8881da800040 index:0x0 flags: 0x2fffc0000000200(slab) raw: 02fffc0000000200 ffffea0007160488 ffffea00071aff08 ffff8881da800040 raw: 0000000000000000 ffff8881c59f5000 0000000100000010 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8881c59f4f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8881c59f4f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc > ffff8881c59f5000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8881c59f5080: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff8881c59f5100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== --- This bug is generated by a bot. 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