in reply to Re: Net::OpenSSH connection failing with 'muxserver_listen bind(): Not owner'
in thread Net::OpenSSH connection failing with 'muxserver_listen bind(): Not owner'

Truss appears to be a very useful tool I was unaware of. I'm seeing multiple instances of the following line from the output, that I'm guessing is the culprit:

statx("$HOMEDIR/.libnet-openssh-perl/$USERNAME-$REMOTEHOST-78612-88421", 0x000000011000B178, 176, 0) Err#2  ENOENT

I see no attempt from any system call to actually create the file being referenced. The $HOMEDIR/.libnet-openssh-perl directory is empty. Any idea what may be causing OpenSSH to be looking for this file, and/or what I should be doing to correct it?

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Re^3: Net::OpenSSH connection failing with 'muxserver_listen bind(): Not owner'
by salva (Canon) on Sep 01, 2011 at 19:47 UTC
    That statx calls are done by the script process, checking for the UNIX domain socket to appear, but in some place there should be another call from the forked ssh process doing a bind call that fails.

    Anyway, what permissions has $HOMEDIR/.libnet-openssh-perl/?

[reply]
[d/l]
[select]
      Yea, I missed the forked call to the bind. It's here: 
      113710:    _poll(0x2FF1C1D0, 1, 2000)            = 1
113710:    nrecvfrom(4, 0x2FF1E0F0, 1024, 0, 0x2FF1C970, 0x2FF1C1C0) =
+ 133
113710:    close(4)                    = 0
113710:    socket(2, 2, 0)                    = 4
113710:    getsockopt(4, 65535, 4104, 0x2FF1DE14, 0x2FF1DE10) = 0
113710:    connext(4, 0xF027F2E0, 16)            = 0
113710:    send(4, 0x2FF1EC00, 41, 0)            = 41
113710:    _poll(0x2FF1DE90, 1, 2000)            = 1
113710:    nrecvfrom(4, 0x2FF1F4C4, 1024, 0, 0x2FF1E630, 0x2FF1DE80) =
+ 154
113710:    close(4)                    = 0
113710:    access("/etc/krb5.conf", 04)            = 0
113710:    statx("/opt/krb5/etc/krb5.conf", 0x2FF1FB58, 76, 0) Err#2  
+ENOENT
113710:    open(0xD0ADB328, O_RDONLY)            = 4
113710:    fstatx(4, 0x2FF20CF0, 76, 0)            = 0
113710:    kread(4, " Ù _9F <80 T } ¿ Ú ± Q ½".., 20)    = 20
113710:    close(4)                    = 0
113710:    _getpid()                    = 113710
113710:    open("/opt/dcelocal/var/security/creds/dcecred_6e245c24", O
+_RDONLY) = 4
113710:    kfcntl(4, F_SETLKW, 0x2FF208A0)            = 0
113710:    kread(4, "0501", 2)                = 2
113710:    lseek(4, 2, 0)                    = 2
113710:    kread(4, "\0\0\002\0\0\00F r c h l".., 1024)    = 1024
113710:    lseek(4, 2, 0)                    = 2
113710:    kread(4, "\0\0\002\0\0\00F r c h l".., 1024)    = 1024
113710:    lseek(4, -989, 1)                = 37
113710:    lseek(4, 37, 0)                    = 37
113710:    kread(4, "\0\0\002\0\0\00F r c h l".., 1024)    = 1024
113710:    lseek(4, -574, 1)                = 487
113710:    kfcntl(4, F_SETLKW, 0x2FF20C80)            = 0
113710:    close(4)                    = 0
113710:    access("/etc/krb5.conf", 04)            = 0
113710:    statx("/opt/krb5/etc/krb5.conf", 0x2FF1FC68, 76, 0) Err#2  
+ENOENT
113710:    open(0xD0ADB328, O_RDONLY)            = 4
113710:    fstatx(4, 0x2FF20E00, 76, 0)            = 0
113710:    kread(4, "94 ? 7 È k i È : à § ¼ Ç".., 20)    = 20
113710:    close(4)                    = 0
113710:    _getpid()                    = 113710
113710:    access("/etc/krb5.conf", 04)            = 0
113710:    statx("/opt/krb5/etc/krb5.conf", 0x2FF1FD28, 76, 0) Err#2  
+ENOENT
113710:    open(0xD0ADB328, O_RDONLY)            = 4
113710:    fstatx(4, 0x2FF20EC0, 76, 0)            = 0
113710:    kread(4, " Å8A e a ±9F ¤8319 u È !".., 20)    = 20
113710:    close(4)                    = 0
113710:    _getpid()                    = 113710
113710:    kwrite(3, "1D Ø8C Ï a ( > · k [12 <".., 80)    = 80
113710:    _select(4, 0x20043210, 0x00000000, 0x00000000, 0x00000000) 
+= 1
113710:    kread(3, "7F82 à ? $ v s Ý ® · l %".., 8192)    = 32
113710:    socket(1, 1, 0)                    = 4
113710:    umask(127)                    = 18
113710:    bind(4, 0x2FF21030, 87)                Err#1  EPERM
ssh_control_listener bind(): Not owner
113710:    kwrite(2, " s s h _ c o n t r o l _".., 40)    = 40
113710:    _exit(255)

      [download]

      Nothing stands out to me as a possible previous error that might be causing the bind error. I did see the following repeating error in another process that may also be related: 

      477272: kioctl(3, 22528, 0x0000000000000000, 0x0000000000000000)113710
+: ENOTTY

      [download]
      Seems like that'd be expected though since ssh is being run through a Perl module.

      Permissions on .libnet-openssh-perl are set to 700.

[reply]
[d/l]
[select]
        AIX truss may accept some option to make it also dump syscall arguments (as those passed to bind). Otherwise a debugger could be used to inspect them, but this is quite more difficult.

        Calling SSH with the verbose flag may also give some useful information: 

        $ssh=Net::OpenSSH->new($host, master_opts => '-vvv',...)

        [download]
        Finally, witch version of OpenSSH are you using?
[reply]
[d/l]

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