As variable s of struct tipc_subscr type is not initialized in tipc_conn_rcv_from_sock() before it is used in tipc_conn_rcv_sub(), KMSAN reported the following uninit-value type complaint:
================================================================== BUG: KMSAN: uninit-value in tipc_conn_rcv_sub+0x184/0x950 net/tipc/topsrv.c:373 CPU: 0 PID: 66 Comm: kworker/u4:4 Not tainted 4.17.0-rc3+ #88 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: tipc_rcv tipc_conn_recv_work Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x185/0x1d0 lib/dump_stack.c:113 kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067 __msan_warning_32+0x6c/0xb0 mm/kmsan/kmsan_instr.c:683 tipc_conn_rcv_sub+0x184/0x950 net/tipc/topsrv.c:373 tipc_conn_rcv_from_sock net/tipc/topsrv.c:409 [inline] tipc_conn_recv_work+0x3cd/0x560 net/tipc/topsrv.c:424 process_one_work+0x12c6/0x1f60 kernel/workqueue.c:2145 worker_thread+0x113c/0x24f0 kernel/workqueue.c:2279 kthread+0x539/0x720 kernel/kthread.c:239 ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:412 Local variable description: ----s.i@tipc_conn_recv_work Variable was created at: tipc_conn_recv_work+0x65/0x560 net/tipc/topsrv.c:419 process_one_work+0x12c6/0x1f60 kernel/workqueue.c:2145 ================================================================== Kernel panic - not syncing: panic_on_warn set ... CPU: 0 PID: 66 Comm: kworker/u4:4 Tainted: G B 4.17.0-rc3+ Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: tipc_rcv tipc_conn_recv_work Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x185/0x1d0 lib/dump_stack.c:113 panic+0x39d/0x940 kernel/panic.c:184 kmsan_report+0x238/0x240 mm/kmsan/kmsan.c:1083 __msan_warning_32+0x6c/0xb0 mm/kmsan/kmsan_instr.c:683 tipc_conn_rcv_sub+0x184/0x950 net/tipc/topsrv.c:373 tipc_conn_rcv_from_sock net/tipc/topsrv.c:409 [inline] tipc_conn_recv_work+0x3cd/0x560 net/tipc/topsrv.c:424 process_one_work+0x12c6/0x1f60 kernel/workqueue.c:2145 worker_thread+0x113c/0x24f0 kernel/workqueue.c:2279 kthread+0x539/0x720 kernel/kthread.c:239 ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:412 Dumping ftrace buffer: (ftrace buffer empty) Kernel Offset: disabled Rebooting in 86400 seconds.. Reported-by: syzbot+8951a3065ee7fd6d6...@syzkaller.appspotmail.com Signed-off-by: Ying Xue <ying....@windriver.com> --- net/tipc/topsrv.c | 1 + 1 file changed, 1 insertion(+) diff --git a/net/tipc/topsrv.c b/net/tipc/topsrv.c index c8e34ef..fe47a62 100644 --- a/net/tipc/topsrv.c +++ b/net/tipc/topsrv.c @@ -397,6 +397,7 @@ static int tipc_conn_rcv_from_sock(struct tipc_conn *con) struct kvec iov; int ret; + memset(&s, 0, sizeof(s)); iov.iov_base = &s; iov.iov_len = sizeof(s); msg.msg_name = NULL; -- 2.7.4