BUG: Zmq abort() due to Bad file descriptor (zeromq-4.3.3/src/epoll.cpp:100)

[jeff277]

Please use this template for reporting suspected bugs or requests for help.

Issue description

When the zmq server has not been running, the zmq client may crash。

similar problem：#2103

It crashed 3 times a day, I think the frequency is quite high, I can provide more information or independent test cases

Environment

root@OpenWrt:~# opkg info libzmq-nc
Package: libzmq-nc
Version: 4.3.3-2
Depends: libc, libuuid1, libpthread, librt, libstdcpp6
Provides: libzmq
Status: install user installed
Architecture: x86_64
Installed-Time: 1670919771

root@OpenWrt:~# uname -a
Linux OpenWrt 4.14.241 #0 SMP Thu Jul 29 19:50:28 2021 x86_64 GNU/Linux

---

code :

This is Makefile for ZeroMQ in OpenWrt.org

PKG_NAME:=zeromq
PKG_VERSION:=4.3.3
PKG_RELEASE:=2

PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.gz
PKG_SOURCE_URL:=https://github.com/zeromq/libzmq/releases/download/v$(PKG_VERSION)
PKG_HASH:=9d9285db37ae942ed0780c016da87060497877af45094ff9e1a1ca736e3875a2

• libzmq version (commit hash if unreleased):
• OS: Linux(openwrt 1907)

Minimal test code / Steps to reproduce the issue

1. my initialization code

void
zmq_fd_create(xxx_zmq_fd_t *zmq_fd)
{
int snd_hwm = 10;
zmq_fd->ctx = new zmq::context_t (1);
zmq_fd->client = new zmq::socket_t (*zmq_fd->ctx, ZMQ_PUB);
zmq_fd->client->setsockopt (ZMQ_SNDHWM, &snd_hwm, sizeof (snd_hwm));
zmq_fd->client->setsockopt(ZMQ_LINGER, 0);
zmq_fd->client->connect("tcp://localhost:50000");
}

2. Note that the ZeroMQ server is not started. No program is listening on port tcp:50000

3. The zeromq client sends data once per second, the code is as follows：

zmq_fd->client->send(msg, zmq::send_flags::none)

4、The program crashes after running continuously for 1 to 8 hours

What's the actual result? (include assertion message & call stack if applicable)

#0 a_crash () at ./arch/x86_64/atomic_arch.h:108
#1 abort () at src/exit/abort.c:29
#2 0x00007f64bf3315a1 in zmq::zmq_abort(char const*) () from /home/lifei/Documents/x86/slab_sys_2.0/staging_dir/target-x86_64_musl/root-x86/usr/lib/libzmq.so.5
#3 0x00007f64bf330f88 in zmq::epoll_t::add_fd(int, zmq::i_poll_events*) () from /home/lifei/Documents/x86/slab_sys_2.0/staging_dir/target-x86_64_musl/root-x86/usr/lib/libzmq.so.5
#4 0x00007f64bf3521e5 in zmq::tcp_connecter_t::start_connecting() () from /home/lifei/Documents/x86/slab_sys_2.0/staging_dir/target-x86_64_musl/root-x86/usr/lib/libzmq.so.5
#5 0x00007f64bf33fa3b in zmq::poller_base_t::execute_timers() () from /home/lifei/Documents/x86/slab_sys_2.0/staging_dir/target-x86_64_musl/root-x86/usr/lib/libzmq.so.5
#6 0x00007f64bf330d59 in zmq::epoll_t::loop() () from /home/lifei/Documents/x86/slab_sys_2.0/staging_dir/target-x86_64_musl/root-x86/usr/lib/libzmq.so.5
#7 0x00007f64bf352d74 in thread_routine () from /home/lifei/Documents/x86/slab_sys_2.0/staging_dir/target-x86_64_musl/root-x86/usr/lib/libzmq.so.5
#8 0x00007f64bf641a3e in start (p=0x7f64bf056aa8) at src/thread/pthread_create.c:192
#9 0x00007f64bf643bf0 in __clone () at src/thread/x86_64/clone.s:22

What's the expected result?

The program runs continuously for 7 days without crashing

[jeff277]

Here is another call stack information in the same environment

(gdb) bt #0 a_crash () at ./arch/x86_64/atomic_arch.h:108 #1 abort () at src/exit/abort.c:29 #2 0x00007f3e5db0b5a1 in zmq::zmq_abort(char const*) () from /home/lifei/Documents/x86/slab_sys_2.0/staging_dir/target-x86_64_musl/root-x86/usr/lib/libzmq.so.5 #3 0x00007f3e5db3f745 in zmq::stream_connecter_base_t::close() () from /home/lifei/Documents/x86/slab_sys_2.0/staging_dir/target-x86_64_musl/root-x86/usr/lib/libzmq.so.5 #4 0x00007f3e5db2c252 in zmq::tcp_connecter_t::start_connecting() () from /home/lifei/Documents/x86/slab_sys_2.0/staging_dir/target-x86_64_musl/root-x86/usr/lib/libzmq.so.5 #5 0x00007f3e5db19a3b in zmq::poller_base_t::execute_timers() () from /home/lifei/Documents/x86/slab_sys_2.0/staging_dir/target-x86_64_musl/root-x86/usr/lib/libzmq.so.5 #6 0x00007f3e5db0ad59 in zmq::epoll_t::loop() () from /home/lifei/Documents/x86/slab_sys_2.0/staging_dir/target-x86_64_musl/root-x86/usr/lib/libzmq.so.5 #7 0x00007f3e5db2cd74 in thread_routine () from /home/lifei/Documents/x86/slab_sys_2.0/staging_dir/target-x86_64_musl/root-x86/usr/lib/libzmq.so.5 #8 0x00007f3e5de1ba3e in start (p=0x7f3e5d80daa8) at src/thread/pthread_create.c:192 #9 0x00007f3e5de1dbf0 in __clone () at src/thread/x86_64/clone.s:22 Backtrace stopped: frame did not save the PC