scp not shutting down in 2.1.1p4

[Kevin Steves]

Here are some trace (tusc) and stacks traces from HP-UX 11.0.

scp trace output:

write(2, "5 3   X \n", 5) ...................................................... = 5
write(6, "C 0 6 6 4   5 3   X \n", 11) ......................................... = 11
read(7, "\0", 1) ............................................................... = 1
fstat(3, 0x7bff1084) ........................................................... = 0
gettimeofday(0x40002780, NULL) ................................................. = 0
setpgrp(0) ..................................................................... = 8809
ioctl(1, TIOCGPGRP, 0x7bff1280) ................................................ = 0
gettimeofday(0x7bff10b0, NULL) ................................................. = 0
ioctl(1, TIOCGWINSZ, 0x7bff1280) ............................................... = 0
X                      0% |                                                   |     0       --:-- ETAwrite(1, "\rX                             ".., 102) ............................ = 102
sigsetreturn(0x7bfcba1a, 0x6211988, 1392) ...................................... = 0
sigaction(SIGALRM, 0x7bff11e8, NULL) ........................................... = 0
setitimer(ITIMER_REAL, 0x7bff1280, NULL) ....................................... = 0
read(3, "G e n e r i c S y s N a m e   [ ".., 53) .............................. = 53
write(6, "G e n e r i c S y s N a m e   [ ".., 53) ............................. = 53
ioctl(1, TIOCGPGRP, 0x7bff1280) ................................................ = 0
gettimeofday(0x7bff10b0, NULL) ................................................. = 0
ioctl(1, TIOCGWINSZ, 0x7bff1280) ............................................... = 0
X                    100% |***************************************************|    53       00:00    write(1, "\rX                             ".., 102) ............................ = 102
setitimer(ITIMER_REAL, 0x7bff1280, NULL) ....................................... = 0

write(1, "\n", 1) .............................................................. = 1
close(3) ....................................................................... = 0
write(6, "\0", 1) .............................................................. = 1
read(7, "\0", 1) ............................................................... = 1
exit(0) ........................................................................ WIFEXITED(0)

stack trace of blocked scp ssh child:

(gdb) attach 8613
Attaching to process 8613
Reading symbols from /opt/openssh-2.1.1p4/bin/ssh...done.
warning: The shared libraries were not privately mapped; setting a
breakpoint in a shared library will not work until you rerun the program.

Reading symbols from /usr/lib/libnsl.1...done.
Reading symbols from /usr/lib/libxti.2...done.
Reading symbols from /usr/lib/libsec.2...done.
Reading symbols from /usr/lib/libm.2...done.
Reading symbols from /usr/lib/libpam.1...done.
Reading symbols from /usr/lib/libc.2...done.
Reading symbols from /usr/lib/libdld.2...done.
Reading symbols from /usr/lib/libnss_files.1...done.
Reading symbols from /usr/lib/libnss_dns.1...done.
0xc01ed428 in _select_sys () from /usr/lib/libc.2
(gdb) bt
#0  0xc01ed428 in _select_sys () from /usr/lib/libc.2
#1  0xc01f8fa8 in select () from /usr/lib/libc.2
#2  0x1a004 in client_wait_until_can_do_something (readset=0x7bff0ddc, writeset=0x7bff0edc)
    at clientloop.c:368
#3  0x1b248 in client_loop (have_pty=0, escape_char_arg=-1) at clientloop.c:824
#4  0x12a48 in ssh_session () at ssh.c:874
#5  0x12000 in main (ac=5, av=0x7bff0514) at ssh.c:670

stack trace of server blocked sshd:

Attaching to process 8777
Reading symbols from /opt/ssh/sbin/sshd...done.
warning: The shared libraries were not privately mapped; setting a
breakpoint in a shared library will not work until you rerun the program.

Reading symbols from /usr/lib/libnsl.1...done.
Reading symbols from /usr/lib/libxti.2...done.
Reading symbols from /usr/lib/libsec.2...done.
Reading symbols from /usr/lib/libm.2...done.
Reading symbols from /usr/lib/libpam.1...done.
Reading symbols from /usr/lib/libc.2...done.
Reading symbols from /usr/lib/libdld.2...done.
Reading symbols from /usr/lib/libnss_files.1...done.
Reading symbols from /usr/lib/libnss_dns.1...done.
Reading symbols from /usr/lib/security/libpam_unix.1...done.
Reading symbols from /usr/lib/libpsm.1...done.
0xc01ed428 in _select_sys () from /usr/lib/libc.2
(gdb) bt
#0  0xc01ed428 in _select_sys () from /usr/lib/libc.2
#1  0xc01f8fa8 in select () from /usr/lib/libc.2
#2  0x1b90c in wait_until_can_do_something (readset=0x7bff0ea8, writeset=0x7bff0fa8, 
    max_time_milliseconds=0) at serverloop.c:232
#3  0x1c490 in server_loop (pid=8778, fdin_arg=8, fdout_arg=8, fderr_arg=10) at serverloop.c:519
#4  0x1e408 in do_exec_no_pty (s=0x4001d540, command=0x4002c910 "scp -t y", pw=0x7bff0cac)
    at session.c:500
#5  0x1e060 in do_authenticated (pw=0x7bff0cac) at session.c:358
#6  0x13d08 in do_authentication () at auth1.c:535
#7  0x12010 in main (ac=1, av=0x7bff02c4) at sshd.c:1003

stack trace "hung" scp process:

Attaching to process 8893
Reading symbols from /usr/src/openssh/openssh-2.1.1p4/scp...done.
warning: The shared libraries were not privately mapped; setting a
breakpoint in a shared library will not work until you rerun the program.

Reading symbols from /usr/lib/libnsl.1...done.
Reading symbols from /usr/lib/libxti.2...done.
Reading symbols from /usr/lib/libsec.2...done.
Reading symbols from /usr/lib/libm.2...done.
Reading symbols from /usr/lib/libpam.1...done.
Reading symbols from /usr/lib/libc.2...done.
Reading symbols from /usr/lib/libdld.2...done.
Reading symbols from /usr/lib/libnss_files.1...done.
0xc01ed230 in _read_sys () from /usr/lib/libc.2
(gdb) bt
#0  0xc01ed230 in _read_sys () from /usr/lib/libc.2
#1  0xc01f85e4 in read () from /usr/lib/libc.2
#2  0x82a8 in atomicio (f=0x400026d2 <SD$endc+122>, fd=0, _s=0x7bff03c0 "C0664 53 X", n=1) at atomicio.c:46
#3  0x625c in sink (argc=1, argv=0x7bff014c) at scp.c:702
#4  0x4c08 in main (argc=1, argv=0x7bff014c) at scp.c:335