From: Stefan Raspl <raspl@linux.ibm.com>
Subject: net/smc: init conn.tx_work & conn.send_lock sooner
Patch-mainline: v4.18-rc1
Git-commit: be7f3e59997b7744e8be153b76fca28ac5b71354
References: FATE#325694, LTC#167874, bsc#1113480

Summary:     net/smc: SMC-R MVP
Description: Add latest upstream patches to push SMC-R to the MVP level

Upstream-Description:

             net/smc: init conn.tx_work & conn.send_lock sooner

             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@google.com>
             Cc: Ursula Braun <ubraun@linux.ibm.com>
             Cc: linux-s390@vger.kernel.org
             Reported-by: syzbot <syzkaller@googlegroups.com>
             Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: Stefan Raspl <raspl@linux.ibm.com>
Acked-by: Petr Tesarik <ptesarik@suse.com>
---
 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(-)

--- a/net/smc/af_smc.c
+++ b/net/smc/af_smc.c
@@ -193,8 +193,10 @@ static struct sock *smc_sock_alloc(struc
 	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);
 
--- a/net/smc/smc_tx.c
+++ b/net/smc/smc_tx.c
@@ -449,7 +449,7 @@ out_unlock:
 /* 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,
@@ -511,6 +511,4 @@ void smc_tx_consumer_update(struct smc_c
 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);
 }
--- a/net/smc/smc_tx.h
+++ b/net/smc/smc_tx.h
@@ -26,6 +26,7 @@ static inline int smc_tx_prepared_sends(
 	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);