smbd crashes with SIGABRT during SMB2 tree connect when two CephFS shares are configured against the same filesystem with the same credentials but differ in their ceph_new:proxy setting. The crash is reproducible by mapping a proxy-enabled share after a non-proxy share, or vice versa.

Core was generated by `/usr/local/sbin/smbd --foreground --no-process-group'.
  Program terminated with signal SIGABRT, Aborted.
  #0  __pthread_kill_implementation (threadid=<optimized out>, signo=signo@entry=6, no_tid=no_tid@entry=0) at pthread_kill.c:44
  44          return INTERNAL_SYSCALL_ERROR_P (ret) ? INTERNAL_SYSCALL_ERRNO (ret) : 0;
  [Current thread is 1 (Thread 0x7f3fdd28ef40 (LWP 176845))]
  (gdb) bt
  #0  __pthread_kill_implementation (threadid=<optimized out>, signo=signo@entry=6, no_tid=no_tid@entry=0) at pthread_kill.c:44
  #1  0x00007f3fe040ad93 in __pthread_kill_internal (threadid=<optimized out>, signo=6) at pthread_kill.c:89
  #2  0x00007f3fe03afe8e in __GI_raise (sig=sig@entry=6) at ../sysdeps/posix/raise.c:26
  #3  0x00007f3fe03977b3 in __GI_abort () at abort.c:77
  #4  0x00007f3fe09a20ae in dump_core () at ../../source3/lib/dumpcore.c:339
  #5  0x00007f3fe0994aac in smb_panic_s3 (why=0x7ffd72098d50 "Signal 11: Segmentation fault") at ../../source3/lib/util.c:698
  #6  0x00007f3fe05e4ba9 in smb_panic (why=0x7ffd72098d50 "Signal 11: Segmentation fault") at ../../lib/util/fault.c:209
  #7  0x00007f3fe05e4658 in fault_report (sig=11) at ../../lib/util/fault.c:83
  #8  0x00007f3fe05e466d in sig_fault (sig=11) at ../../lib/util/fault.c:94
  #9  <signal handler called>
  #10 0x00007f3fc98c2ab7 in RWRef<Client::_state>::RWRef (this=0x7ffd720993f0, s=..., require=Client::CLIENT_MOUNTING, ir=true) at /root/workspace/ceph.git/src/client/RWRef.h:156
  #11 0x00007f3fc98570fe in Client::getcwd (this=0xa24132addf876ddf, dir=Python Exception <class 'OverflowError'>: int too big to convert, perms=...) at
  /root/workspace/ceph.git/src/client/Client.cc:13517
  #12 0x00007f3fc980a7d6 in ceph_mount_info::get_cwd (this=0x1d87b3b0, perms=...) at /root/workspace/ceph.git/src/libcephfs.cc:321
  #13 ceph_getcwd (cmount=0x1d87b3b0) at /root/workspace/ceph.git/src/libcephfs.cc:691
  #14 0x00007f3fdb2a86ad in vfs_ceph_ll_walk (handle=0x1db7ca10, name=0x1db7a4d0 "/volumes/_nogroup/subvol/03da1a1a-9497-4322-a2e1-fcccc6cecc22", pin=0x7ffd72099570, stx=0x7ffd720994e0,
  want=256, flags=0) at ../../source3/modules/vfs_ceph_new.c:1060
  #15 0x00007f3fdb2ad50e in vfs_ceph_iget (handle=0x1db7ca10, name=0x1db7a4d0 "/volumes/_nogroup/subvol/03da1a1a-9497-4322-a2e1-fcccc6cecc22", flags=0, iref=0x7ffd720995b0) at
  ../../source3/modules/vfs_ceph_new.c:2255
  #16 0x00007f3fdb2ad94c in vfs_ceph_open_share_root (handle=0x1db7ca10, root_fsp=0x1d96d850, connectpath=0x1db7a4d0 "/volumes/_nogroup/subvol/03da1a1a-9497-4322-a2e1-fcccc6cecc22") at
  ../../source3/modules/vfs_ceph_new.c:2327
  #17 0x00007f3fe0a86268 in smb_vfs_call_open_share_root (handle=0x1db7ca10, root_fsp=0x1d96d850, connectpath=0x1db7a4d0 "/volumes/_nogroup/subvol/03da1a1a-9497-4322-a2e1-fcccc6cecc22") at
  ../../source3/smbd/vfs.c:1241
  #18 0x00007f3fe0aa4057 in make_connection_snum (xconn=0x1d8744a0, conn=0x1d976eb0, snum=4, session=0x1d854810, pdev=0x7f3fe0bffb33 "???") at ../../source3/smbd/smb2_service.c:800
  #19 0x00007f3fe0aa45a8 in make_connection_smb2 (req=0x1d8781d0, tcon=0x1d885df0, snum=4, pdev=0x7f3fe0bffb33 "???", pstatus=0x7ffd7209990c) at ../../source3/smbd/smb2_service.c:902
  #20 0x00007f3fe0aca591 in smbd_smb2_tree_connect (req=0x1d8781d0, in_path=0x1d878630 "\\\\192.168.122.103\\cephfs-subvol-new", out_share_type=0x1d878978 "", out_share_flags=0x1d87897c,
  out_capabilities=0x1d878980, out_maximal_access=0x1d878984, out_tree_id=0x1d878988, disconnect=0x1d87898c) at ../../source3/smbd/smb2_tcon.c:383
  #21 0x00007f3fe0acad94 in smbd_smb2_tree_connect_send (mem_ctx=0x1d8781d0, ev=0x1d84c9e0, smb2req=0x1d8781d0, in_flags=0, in_path=0x1d878630 "\\\\192.168.122.103\\cephfs-subvol-new") at
  ../../source3/smbd/smb2_tcon.c:592
  #22 0x00007f3fe0ac96db in smbd_smb2_request_process_tcon (req=0x1d8781d0) at ../../source3/smbd/smb2_tcon.c:106
  #23 0x00007f3fe0aba0ed in smbd_smb2_request_dispatch (req=0x1d8781d0) at ../../source3/smbd/smb2_server.c:3497
  #24 0x00007f3fe0ac175b in smbd_smb2_advance_incoming (xconn=0x1d8744a0, n=142) at ../../source3/smbd/smb2_server.c:5221
  #25 0x00007f3fe0ac1ad0 in smbd_smb2_io_handler (xconn=0x1d8744a0, fde_flags=1) at ../../source3/smbd/smb2_server.c:5332
  #26 0x00007f3fe0ac1b71 in smbd_smb2_connection_handler (ev=0x1d84c9e0, fde=0x1d86ef90, flags=1, private_data=0x1d8744a0) at ../../source3/smbd/smb2_server.c:5359
  #27 0x00007f3fe0c7be01 in tevent_common_invoke_fd_handler (fde=0x1d86ef90, flags=1, removed=0x0) at ../../lib/tevent/tevent_fd.c:174
  #28 0x00007f3fe0c88596 in epoll_event_loop (epoll_ev=0x1d84cf90, tvalp=0x7ffd72099f90) at ../../lib/tevent/tevent_epoll.c:699
  #29 0x00007f3fe0c88c7f in epoll_event_loop_once (ev=0x1d84c9e0, location=0x7f3fe0bf3ef0 "../../source3/smbd/smb2_process.c:2180") at ../../lib/tevent/tevent_epoll.c:929
  #30 0x00007f3fe0c84265 in std_event_loop_once (ev=0x1d84c9e0, location=0x7f3fe0bf3ef0 "../../source3/smbd/smb2_process.c:2180") at ../../lib/tevent/tevent_standard.c:110
  #31 0x00007f3fe0c7a76a in _tevent_loop_once (ev=0x1d84c9e0, location=0x7f3fe0bf3ef0 "../../source3/smbd/smb2_process.c:2180") at ../../lib/tevent/tevent.c:860
  #32 0x00007f3fe0c7aabb in tevent_common_loop_wait (ev=0x1d84c9e0, location=0x7f3fe0bf3ef0 "../../source3/smbd/smb2_process.c:2180") at ../../lib/tevent/tevent.c:989
  #33 0x00007f3fe0c8430a in std_event_loop_wait (ev=0x1d84c9e0, location=0x7f3fe0bf3ef0 "../../source3/smbd/smb2_process.c:2180") at ../../lib/tevent/tevent_standard.c:141
  #34 0x00007f3fe0c7ab61 in _tevent_loop_wait (ev=0x1d84c9e0, location=0x7f3fe0bf3ef0 "../../source3/smbd/smb2_process.c:2180") at ../../lib/tevent/tevent.c:1008
  #35 0x00007f3fe0aa172e in smbd_process (ev_ctx=0x1d84c9e0, msg_ctx=0x1d849120, sock_fd=36, interactive=false, transport_type=SMB_TRANSPORT_TYPE_TCP) at
  ../../source3/smbd/smb2_process.c:2180
  #36 0x0000000000404f21 in smbd_accept_connection (ev=0x1d84c9e0, fde=0x1d86ee80, flags=1, private_data=0x1d86a6a0) at ../../source3/smbd/server.c:1387
  #37 0x00007f3fe0c7be01 in tevent_common_invoke_fd_handler (fde=0x1d86ee80, flags=1, removed=0x0) at ../../lib/tevent/tevent_fd.c:174
  #38 0x00007f3fe0c88596 in epoll_event_loop (epoll_ev=0x1d84cf90, tvalp=0x7ffd7209a400) at ../../lib/tevent/tevent_epoll.c:699
  #39 0x00007f3fe0c88c7f in epoll_event_loop_once (ev=0x1d84c9e0, location=0x4118e8 "../../source3/smbd/server.c:1784") at ../../lib/tevent/tevent_epoll.c:929
  #40 0x00007f3fe0c84265 in std_event_loop_once (ev=0x1d84c9e0, location=0x4118e8 "../../source3/smbd/server.c:1784") at ../../lib/tevent/tevent_standard.c:110
  #41 0x00007f3fe0c7a76a in _tevent_loop_once (ev=0x1d84c9e0, location=0x4118e8 "../../source3/smbd/server.c:1784") at ../../lib/tevent/tevent.c:860
  #42 0x00007f3fe0c7aabb in tevent_common_loop_wait (ev=0x1d84c9e0, location=0x4118e8 "../../source3/smbd/server.c:1784") at ../../lib/tevent/tevent.c:989
  #43 0x00007f3fe0c8430a in std_event_loop_wait (ev=0x1d84c9e0, location=0x4118e8 "../../source3/smbd/server.c:1784") at ../../lib/tevent/tevent_standard.c:141
  #44 0x00007f3fe0c7ab61 in _tevent_loop_wait (ev=0x1d84c9e0, location=0x4118e8 "../../source3/smbd/server.c:1784") at ../../lib/tevent/tevent.c:1008
  #45 0x0000000000405cae in smbd_parent_loop (ev_ctx=0x1d84c9e0, parent=0x1d85c7e0) at ../../source3/smbd/server.c:1784
  #46 0x00000000004090c4 in main (argc=3, argv=0x7ffd7209aa68) at ../../source3/smbd/server.c:2822