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: 01d2f7e2cdd3 ("net/smc: sockopts TCP_NODELAY and TCP_CORK") Signed-off-by: Eric Dumazet <edumazet@xxxxxxxxxx> Cc: Ursula Braun <ubraun@xxxxxxxxxxxxx> Cc: linux-s390@xxxxxxxxxxxxxxx Reported-by: syzbot <syzkaller@xxxxxxxxxxxxxxxx> --- net/smc/af_smc.c | 2 ++ net/smc/smc_tx.c | 4 +--- net/smc/smc_tx.h | 1 + 3 files changed, 4 insertions(+), 3 deletions(-) diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c index d15762b057c0d8d4167feca9a4c41f0408604c37..6ad4f6c771c3fa63d3ae714dbe65879910963a21 100644 --- a/net/smc/af_smc.c +++ b/net/smc/af_smc.c @@ -193,8 +193,10 @@ static struct sock *smc_sock_alloc(struct net *net, struct socket *sock, sk->sk_protocol = protocol; smc = smc_sk(sk); INIT_WORK(&smc->tcp_listen_work, smc_tcp_listen_work); + INIT_DELAYED_WORK(&smc->conn.tx_work, smc_tx_work); INIT_LIST_HEAD(&smc->accept_q); spin_lock_init(&smc->accept_q_lock); + spin_lock_init(&smc->conn.send_lock); sk->sk_prot->hash(sk); sk_refcnt_debug_inc(sk); diff --git a/net/smc/smc_tx.c b/net/smc/smc_tx.c index 58dfe0bd9d6075b5d3db97c659999b364b97da73..08a7de98bb031b5d2256e3238236108749e7ae39 100644 --- a/net/smc/smc_tx.c +++ b/net/smc/smc_tx.c @@ -450,7 +450,7 @@ int smc_tx_sndbuf_nonempty(struct smc_connection *conn) /* Wakeup sndbuf consumers from process context * since there is more data to transmit */ -static void smc_tx_work(struct work_struct *work) +void smc_tx_work(struct work_struct *work) { struct smc_connection *conn = container_of(to_delayed_work(work), struct smc_connection, @@ -512,6 +512,4 @@ void smc_tx_consumer_update(struct smc_connection *conn) void smc_tx_init(struct smc_sock *smc) { smc->sk.sk_write_space = smc_tx_write_space; - INIT_DELAYED_WORK(&smc->conn.tx_work, smc_tx_work); - spin_lock_init(&smc->conn.send_lock); } diff --git a/net/smc/smc_tx.h b/net/smc/smc_tx.h index 78255964fa4dc1c69f96548e035e74a167999a62..8f64b12bf03c1b52c599b1239784a404efe65dae 100644 --- a/net/smc/smc_tx.h +++ b/net/smc/smc_tx.h @@ -27,6 +27,7 @@ static inline int smc_tx_prepared_sends(struct smc_connection *conn) return smc_curs_diff(conn->sndbuf_size, &sent, &prep); } +void smc_tx_work(struct work_struct *work); void smc_tx_init(struct smc_sock *smc); int smc_tx_sendmsg(struct smc_sock *smc, struct msghdr *msg, size_t len); int smc_tx_sndbuf_nonempty(struct smc_connection *conn); -- 2.17.0.441.gb46fe60e1d-goog -- To unsubscribe from this list: send the line "unsubscribe linux-s390" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html