Created attachment 1484642 [details]
coredump and program

glusterfs version:

$ glusterfs --version
glusterfs 5.0rc0

Commit on top of release 5 branch: f4594a3c88cb0a76e260010d57632dc1c718fd5f


Libgfapi program coredumps when glfs_fini() is called on an uninitialised fs object. The libgfapi-python tests uncovered this regression:


Reproducer C program:

$ cat example.c 
#include <stdio.h>
#include <unistd.h>
#include <glusterfs/api/glfs.h>

int main (int argc, char** argv) {
        glfs_t *fs = NULL;
        int ret;

        // provide a nonexistent volume name
        fs = glfs_new ("volume_name");
        if (!fs) {
                return -1;
        }

        ret = glfs_set_volfile_server (fs, "tcp", "localhost", 24007);
        if (ret != 0) {
                return ret;
        }

        ret = glfs_init (fs); // this will fail, obviously

        ret = glfs_fini(fs); // this coredumps which is a regression
        if (ret != 0) {
                return ret;
        }

        return 0;
}

$ ./reproducer 
Segmentation fault (core dumped)



[root@gd2-1 coredump]# gdb -c core.reproducer.1000.ee68dfad9759484eb3be6813dc5d901e.8221.1537351962000000 /home/ppai/src/glusterfs/reproducer
GNU gdb (GDB) Fedora 8.0.1-36.fc26
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Reading symbols from /home/ppai/src/glusterfs/reproducer...(no debugging symbols found)...done.
[New LWP 8229]
[New LWP 8222]
[New LWP 8223]
[New LWP 8224]
[New LWP 8228]
[New LWP 8227]
[New LWP 8221]
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib64/libthread_db.so.1".
Core was generated by `./reproducer'.
Program terminated with signal SIGSEGV, Segmentation fault.
#0  0x00007fcbf9df381f in mgmt_rpc_notify (rpc=0x1b89080, mydata=0x1b815c0, event=RPC_CLNT_DISCONNECT, 
    data=0x0) at glfs-mgmt.c:855
855	                if (rpc_trans->connect_failed)
[Current thread is 1 (Thread 0x7fcbebdca700 (LWP 8229))]
Missing separate debuginfos, use: dnf debuginfo-install libacl-2.2.52-15.fc26.x86_64 libattr-2.4.47-18.fc26.x86_64 libuuid-2.30.2-1.fc26.x86_64 openssl-libs-1.1.0h-3.fc26.x86_64 zlib-1.2.11-2.fc26.x86_64





(gdb) t a a bt

Thread 7 (Thread 0x7fcbfa228180 (LWP 8221)):
#0  0x00007fcbf8335f26 in futex_abstimed_wait_cancelable (private=<optimized out>, abstime=0x7fffa37f2560, expected=0, futex_word=0x1b79758) at ../sysdeps/unix/sysv/linux/futex-internal.h:205
#1  __pthread_cond_wait_common (abstime=0x7fffa37f2560, mutex=0x1b79708, cond=0x1b79730) at pthread_cond_wait.c:539
#2  __pthread_cond_timedwait (cond=0x1b79730, mutex=0x1b79708, abstime=0x7fffa37f2560) at pthread_cond_wait.c:667
#3  0x00007fcbf90e6f8c in event_dispatch_destroy (event_pool=0x1b766e0) at event.c:272
#4  0x00007fcbf9df0bbe in pub_glfs_fini (fs=0x1afd140) at glfs.c:1348
#5  0x000000000040072e in main ()

Thread 6 (Thread 0x7fcbed1f2700 (LWP 8227)):
#0  0x00007fcbf9ae5c0d in nanosleep () at ../sysdeps/unix/syscall-template.S:84
#1  0x00007fcbf90c1d1f in gf_timer_proc (data=0x1b81000) at timer.c:195
#2  0x00007fcbf832f36d in start_thread (arg=0x7fcbed1f2700) at pthread_create.c:456
#3  0x00007fcbf9b21b4f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:97

Thread 5 (Thread 0x7fcbec7ee700 (LWP 8228)):
#0  0x00007fcbf833089d in pthread_join (threadid=140513812195072, thread_return=0x0) at pthread_join.c:90
#1  0x00007fcbf9129060 in event_dispatch_epoll (event_pool=0x1b766e0) at event-epoll.c:758
#2  0x00007fcbf90e6b02 in event_dispatch (event_pool=0x1b766e0) at event.c:116
#3  0x00007fcbf9def750 in glfs_poller (data=0x1afd140) at glfs.c:717
#4  0x00007fcbf832f36d in start_thread (arg=0x7fcbec7ee700) at pthread_create.c:456
#5  0x00007fcbf9b21b4f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:97

Thread 4 (Thread 0x7fcbf6194700 (LWP 8224)):
#0  0x00007fcbf8335f26 in futex_abstimed_wait_cancelable (private=<optimized out>, abstime=0x7fcbf6193e50, expected=0, futex_word=0x1b3f4b0) at ../sysdeps/unix/sysv/linux/futex-internal.h:205
#1  __pthread_cond_wait_common (abstime=0x7fcbf6193e50, mutex=0x1b3f460, cond=0x1b3f488) at pthread_cond_wait.c:539
#2  __pthread_cond_timedwait (cond=0x1b3f488, mutex=0x1b3f460, abstime=0x7fcbf6193e50) at pthread_cond_wait.c:667
#3  0x00007fcbf90ff4bd in syncenv_task (proc=0x1b3bbe0) at syncop.c:591
#4  0x00007fcbf90ff758 in syncenv_processor (thdata=0x1b3bbe0) at syncop.c:681
#5  0x00007fcbf832f36d in start_thread (arg=0x7fcbf6194700) at pthread_create.c:456
#6  0x00007fcbf9b21b4f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:97

Thread 3 (Thread 0x7fcbf6995700 (LWP 8223)):
#0  0x00007fcbf8335f26 in futex_abstimed_wait_cancelable (private=<optimized out>, abstime=0x7fcbf6994e50, expected=0, futex_word=0x1b3f4b0) at ../sysdeps/unix/sysv/linux/futex-internal.h:205
#1  __pthread_cond_wait_common (abstime=0x7fcbf6994e50, mutex=0x1b3f460, cond=0x1b3f488) at pthread_cond_wait.c:539
#2  __pthread_cond_timedwait (cond=0x1b3f488, mutex=0x1b3f460, abstime=0x7fcbf6994e50) at pthread_cond_wait.c:667
#3  0x00007fcbf90ff4bd in syncenv_task (proc=0x1b3b820) at syncop.c:591
#4  0x00007fcbf90ff758 in syncenv_processor (thdata=0x1b3b820) at syncop.c:681
#5  0x00007fcbf832f36d in start_thread (arg=0x7fcbf6995700) at pthread_create.c:456
#6  0x00007fcbf9b21b4f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:97

Thread 2 (Thread 0x7fcbf7c96700 (LWP 8222)):
#0  0x00007fcbf9ae5c0d in nanosleep () at ../sysdeps/unix/syscall-template.S:84
#1  0x00007fcbf9ae5b4a in __sleep (seconds=0) at ../sysdeps/posix/sleep.c:55
#2  0x00007fcbf90e832e in pool_sweeper (arg=0x0) at mem-pool.c:463
#3  0x00007fcbf832f36d in start_thread (arg=0x7fcbf7c96700) at pthread_create.c:456
#4  0x00007fcbf9b21b4f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:97

Thread 1 (Thread 0x7fcbebdca700 (LWP 8229)):
#0  0x00007fcbf9df381f in mgmt_rpc_notify (rpc=0x1b89080, mydata=0x1b815c0, event=RPC_CLNT_DISCONNECT, data=0x0) at glfs-mgmt.c:855
#1  0x00007fcbf95f8295 in rpc_clnt_handle_disconnect (clnt=0x1b89080, conn=0x1b890b0) at rpc-clnt.c:818
#2  0x00007fcbf95f8558 in rpc_clnt_notify (trans=0x1b89230, mydata=0x1b890b0, event=RPC_TRANSPORT_DISCONNECT, data=0x1b89230) at rpc-clnt.c:879
#3  0x00007fcbf95f4889 in rpc_transport_notify (this=0x1b89230, event=RPC_TRANSPORT_DISCONNECT, data=0x1b89230) at rpc-transport.c:525
#4  0x00007fcbebdd228b in socket_event_poll_err (this=0x1b89230, gen=1, idx=0) at socket.c:1301
---Type <return> to continue, or q <return> to quit---
#5  0x00007fcbebdd829f in socket_event_handler (fd=7, idx=0, gen=1, data=0x1b89230, poll_in=1, poll_out=0, poll_err=16) at socket.c:2929
#6  0x00007fcbf9128ad2 in event_dispatch_epoll_handler (event_pool=0x1b766e0, event=0x7fcbebdc9e94) at event-epoll.c:591
#7  0x00007fcbf9128dac in event_dispatch_epoll_worker (data=0x7fcbe4000930) at event-epoll.c:668
#8  0x00007fcbf832f36d in start_thread (arg=0x7fcbebdca700) at pthread_create.c:456
#9  0x00007fcbf9b21b4f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:97


Expected result:
There should not be coredump