On Mon, Jan 7, 2019 at 10:53 AM syzbot <syzbot+b0b1952f5864b4009...@syzkaller.appspotmail.com> wrote: > > Hello, > > syzbot found the following crash on: > > HEAD commit: f1c2f8857c5a Merge tag 'powerpc-4.21-2' of git://git.kerne.. > git tree: upstream > console output: https://syzkaller.appspot.com/x/log.txt?x=16af96bb400000 > kernel config: https://syzkaller.appspot.com/x/.config?x=47c29c309c47af16 > dashboard link: https://syzkaller.appspot.com/bug?extid=b0b1952f5864b4009b09 > compiler: gcc (GCC) 9.0.0 20181231 (experimental) > > Unfortunately, I don't have any reproducer for this crash yet. > > IMPORTANT: if you fix the bug, please add the following tag to the commit: > Reported-by: syzbot+b0b1952f5864b4009...@syzkaller.appspotmail.com
#syz fix: netrom: switch to sock timer API > ------------[ cut here ]------------ > refcount_t: increment on 0; use-after-free. > WARNING: CPU: 1 PID: 3768 at lib/refcount.c:153 refcount_inc_checked > lib/refcount.c:153 [inline] > WARNING: CPU: 1 PID: 3768 at lib/refcount.c:153 > refcount_inc_checked+0x61/0x70 lib/refcount.c:151 > Kernel panic - not syncing: panic_on_warn set ... > CPU: 1 PID: 3768 Comm: syz-executor5 Not tainted 4.20.0+ #11 > 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+0x1db/0x2d0 lib/dump_stack.c:113 > panic+0x2cb/0x65c kernel/panic.c:214 > __warn.cold+0x20/0x48 kernel/panic.c:571 > report_bug+0x263/0x2b0 lib/bug.c:186 > fixup_bug arch/x86/kernel/traps.c:178 [inline] > fixup_bug arch/x86/kernel/traps.c:173 [inline] > do_error_trap+0x11b/0x200 arch/x86/kernel/traps.c:271 > do_invalid_op+0x37/0x50 arch/x86/kernel/traps.c:290 > invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:973 > RIP: 0010:refcount_inc_checked lib/refcount.c:153 [inline] > RIP: 0010:refcount_inc_checked+0x61/0x70 lib/refcount.c:151 > Code: 1d ec 29 c8 06 31 ff 89 de e8 fb 1a f2 fd 84 db 75 dd e8 b2 19 f2 fd > 48 c7 c7 e0 98 81 88 c6 05 cc 29 c8 06 01 e8 df 6e bb fd <0f> 0b eb c1 90 > 66 2e 0f 1f 84 00 00 00 00 00 55 48 89 e5 41 54 49 > RSP: 0018:ffff8880675af460 EFLAGS: 00010282 > RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 > RDX: 0000000000000000 RSI: ffffffff81684ce6 RDI: 0000000000000005 > RBP: ffff8880675af470 R08: ffff88806164e600 R09: ffffed1015ce5021 > R10: ffffed1015ce5020 R11: ffff8880ae728107 R12: ffff88808cf2a940 > R13: ffff88809669c1a0 R14: ffff88808cf2ac28 R15: ffff88808cf2a940 > sock_hold include/net/sock.h:647 [inline] > nr_release+0x62/0x3c0 net/netrom/af_netrom.c:523 > __sock_release+0xd3/0x250 net/socket.c:579 > sock_close+0x1b/0x30 net/socket.c:1141 > __fput+0x3c5/0xb10 fs/file_table.c:278 > ____fput+0x16/0x20 fs/file_table.c:309 > task_work_run+0x1f4/0x2b0 kernel/task_work.c:113 > exit_task_work include/linux/task_work.h:22 [inline] > do_exit+0x19d6/0x2650 kernel/exit.c:867 > do_group_exit+0x177/0x430 kernel/exit.c:970 > get_signal+0x8b4/0x19b0 kernel/signal.c:2517 > do_signal+0x91/0x1ea0 arch/x86/kernel/signal.c:816 > exit_to_usermode_loop+0x2f7/0x3b0 arch/x86/entry/common.c:162 > prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline] > syscall_return_slowpath arch/x86/entry/common.c:268 [inline] > do_syscall_64+0x696/0x800 arch/x86/entry/common.c:293 > entry_SYSCALL_64_after_hwframe+0x49/0xbe > RIP: 0033:0x457ec9 > Code: 6d b7 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 3b b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 > RSP: 002b:00007fb2e6be7cf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca > RAX: fffffffffffffe00 RBX: 000000000073c048 RCX: 0000000000457ec9 > RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000073c048 > RBP: 000000000073c040 R08: 0000000000000000 R09: 0000000000000000 > R10: 0000000000000000 R11: 0000000000000246 R12: 000000000073c04c > R13: 00007fffae482f5f R14: 00007fb2e6be89c0 R15: 000000000073c04c > Kernel Offset: disabled > Rebooting in 86400 seconds.. > > > --- > 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. > > -- > 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/000000000000ea7ffe057edb3156%40google.com. > For more options, visit https://groups.google.com/d/optout.
