> -----Original Message----- > From: Dmitry Vyukov <dvyu...@google.com> > Sent: 13-Dec-18 04:47 > To: Jon Maloy <jon.ma...@ericsson.com> > Cc: syzbot+9845fed98688e01f4...@syzkaller.appspotmail.com; David Miller > <da...@davemloft.net>; LKML <linux-ker...@vger.kernel.org>; netdev > <netdev@vger.kernel.org>; syzkaller-bugs <syzkaller- > b...@googlegroups.com>; tipc-discuss...@lists.sourceforge.net; Ying Xue > <ying....@windriver.com> > Subject: Re: KASAN: use-after-free Read in tipc_group_cong > > On Thu, Dec 13, 2018 at 1:16 AM Jon Maloy <jon.ma...@ericsson.com> > wrote: > > > -----Original Message----- > > > From: syzbot > <syzbot+9845fed98688e01f4...@syzkaller.appspotmail.com> > > > Sent: 12-Dec-18 06:11 > > > To: da...@davemloft.net; Jon Maloy <jon.ma...@ericsson.com>; linux- > > > ker...@vger.kernel.org; netdev@vger.kernel.org; syzkaller- > > > b...@googlegroups.com; tipc-discuss...@lists.sourceforge.net; > > > ying....@windriver.com > > > Subject: KASAN: use-after-free Read in tipc_group_cong > > > > This seems to be an effect of the same bug as reported in > > https://syzkaller.appspot.com/bug?extid=10a9db47c3a0e13eb31c > > Let's do > > #syz dup: KASAN: use-after-free Read in tipc_group_bc_cong > > then. > > > > Cong posted a fix for that one. Did you see the crash after applying his > patch? > > Which patch do you mean? Unfortunately kernel development process is so > that it's not possible to figure out what fixes what.
This one: [Patch net] tipc: check tsk->group in tipc_wait_for_cond() ///jon > > I would just wait for new syzbot results. > > > > > > 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+9845fed98688e01f4...@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. It may contain errors. > > > See https://goo.gl/tpsmEJ for more information about syzbot. > > > syzbot engineers can be reached at syzkal...@googlegroups.com. > > > > > > syzbot will keep track of this bug report. See: > > > https://goo.gl/tpsmEJ#bug-status-tracking for how to communicate > > > with syzbot. > > > syzbot can test patches for this bug, for details see: > > > https://goo.gl/tpsmEJ#testing-patches > > > > -- > > You received this message because you are subscribed to the Google > Groups "syzkaller-bugs" group. > > To unsubscribe from this group and stop receiving emails from it, send an > email to syzkaller-bugs+unsubscr...@googlegroups.com. > > To view this discussion on the web visit > https://groups.google.com/d/msgid/syzkaller- > bugs/DM5PR15MB1513AA1661B9F06198CB0C959AA00%40DM5PR15MB1513. > namprd15.prod.outlook.com. > > For more options, visit https://groups.google.com/d/optout.
