• Eric Dumazet's avatar
    net/smc: init conn.tx_work & conn.send_lock sooner · be7f3e59
    Eric Dumazet authored
    syzkaller found that following program crashes the host :
    
    {
      int fd = socket(AF_SMC, SOCK_STREAM, 0);
      int val = 1;
    
      listen(fd, 0);
      shutdown(fd, SHUT_RDWR);
      setsockopt(fd, 6, TCP_NODELAY, &val, 4);
    }
    
    Simply initialize conn.tx_work & conn.send_lock at socket creation,
    rather than deeper in the stack.
    
    ODEBUG: assert_init not available (active state 0) object type: timer_list hint:           (null)
    WARNING: CPU: 1 PID: 13988 at lib/debugobjects.c:329 debug_print_object+0x16a/0x210 lib/debugobjects.c:326
    Kernel panic - not syncing: panic_on_warn set ...
    
    CPU: 1 PID: 13988 Comm: syz-executor0 Not tainted 4.17.0-rc4+ #46
    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+0x1b9/0x294 lib/dump_stack.c:113
     panic+0x22f/0x4de kernel/panic.c:184
     __warn.cold.8+0x163/0x1b3 kernel/panic.c:536
     report_bug+0x252/0x2d0 lib/bug.c:186
     fixup_bug arch/x86/kernel/traps.c:178 [inline]
     do_error_trap+0x1de/0x490 arch/x86/kernel/traps.c:296
     do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:315
     invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:992
    RIP: 0010:debug_print_object+0x16a/0x210 lib/debugobjects.c:326
    RSP: 0018:ffff880197a37880 EFLAGS: 00010086
    RAX: 0000000000000061 RBX: 0000000000000005 RCX: ffffc90001ed0000
    RDX: 0000000000004aaf RSI: ffffffff8160f6f1 RDI: 0000000000000001
    RBP: ffff880197a378c0 R08: ffff8801aa7a0080 R09: ffffed003b5e3eb2
    R10: ffffed003b5e3eb2 R11: ffff8801daf1f597 R12: 0000000000000001
    R13: ffffffff88d96980 R14: ffffffff87fa19a0 R15: ffffffff81666ec0
     debug_object_assert_init+0x309/0x500 lib/debugobjects.c:692
     debug_timer_assert_init kernel/time/timer.c:724 [inline]
     debug_assert_init kernel/time/timer.c:776 [inline]
     del_timer+0x74/0x140 kernel/time/timer.c:1198
     try_to_grab_pending+0x439/0x9a0 kernel/workqueue.c:1223
     mod_delayed_work_on+0x91/0x250 kernel/workqueue.c:1592
     mod_delayed_work include/linux/workqueue.h:541 [inline]
     smc_setsockopt+0x387/0x6d0 net/smc/af_smc.c:1367
     __sys_setsockopt+0x1bd/0x390 net/socket.c:1903
     __do_sys_setsockopt net/socket.c:1914 [inline]
     __se_sys_setsockopt net/socket.c:1911 [inline]
     __x64_sys_setsockopt+0xbe/0x150 net/socket.c:1911
     do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
     entry_SYSCALL_64_after_hwframe+0x49/0xbe
    
    Fixes: 01d2f7e2
    
     ("net/smc: sockopts TCP_NODELAY and TCP_CORK")
    Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
    Cc: Ursula Braun <ubraun@linux.ibm.com>
    Cc: linux-s390@vger.kernel.org
    Reported-by: default avatarsyzbot <syzkaller@googlegroups.com>
    Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
    be7f3e59