Bug#730744: apache2 stopped working with [error] (38)Function not implemented: apr_socket_accept: (client socket)

[Thibaut VARENE <varenet@zigoo.net>]

Package: apache2.2-common
Version: 2.2.22-13
Severity: normal

I can't tell whether that's an apache2 or libc bug, here's the story:

Apache suddenly stopped working (it was still working a week ago, and there was
no configuration change on the system in the interval). I suspect the last
logrotation triggered this, but unfortunately I can't track it down to an
upgraded packages: I run unattended-upgrades, but there's nothing in the logs
for that period, and I don't remember manually dist-upgrading either,
so I'm really clueless as to what broke.

Symptoms:

Apache won't serve any incoming connection, they just hang forever. Logs are
filled with:

[error] (38)Function not implemented: apr_socket_accept: (client socket)

strace'ing httpd -X shows:

open("/etc/group", O_RDONLY|O_CLOEXEC)  = 12
_llseek(12, 0, [0], SEEK_CUR)           = 0
fstat64(12, {st_mode=S_IFREG|0644, st_size=860, ...}) = 0
mmap2(NULL, 860, PROT_READ, MAP_SHARED, 12, 0) = 0x4802b000
_llseek(12, 860, [860], SEEK_SET)       = 0
fstat64(12, {st_mode=S_IFREG|0644, st_size=860, ...}) = 0
munmap(0x4802b000, 860)                 = 0
close(12)                               = 0
setgroups(1, [33])                      = 0
geteuid()                               = 0
setuid(33)                              = 0
epoll_create1(O_CLOEXEC)                = 12
epoll_ctl(12, EPOLL_CTL_ADD, 5, {EPOLLIN, {u32=1220006224, u64=5239886832996450304}}) = 0
epoll_ctl(12, EPOLL_CTL_ADD, 4, {EPOLLIN, {u32=1220006256, u64=5239886970435403776}}) = 0
epoll_ctl(12, EPOLL_CTL_ADD, 3, {EPOLLIN, {u32=1220006288, u64=5239887107874357248}}) = 0
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x48b81000
semop(1015808, {{0, -1, SEM_UNDO}}, 1)  = 0
epoll_wait(12, {{EPOLLIN, {u32=1220006224, u64=5239886832996450304}}}, 3, 10000) = 1
SYS_344(0x5, 0xbff0f62c, 0xbff0f618, 0x80000, 0x10000) = -1 ENOSYS (Function not implemented)
write(2, "[Fri Nov 29 01:36:32 2013] [erro"..., 100) = 100
semop(1015808, {{0, 1, SEM_UNDO}}, 1)   = 0
close(12)                               = 0

This looks quite like the issue mentioned in this thread:
http://lists.debian.org/debian-powerpc/2013/06/msg00005.html

In particular, I'm also running 2.6.32, which is the minimum version for
wheezy's glibc.

HTH

-- Package-specific info:
List of enabled modules from 'apache2 -M':
  actions* alias auth_basic authn_file authz_default authz_groupfile
  authz_host authz_user autoindex cgi deflate dir env include mime
  negotiation php5 reqtimeout setenvif status userdir
  (A * means that the .conf file for that module is not enabled in
   /etc/apache2/mods-enabled/)
List of enabled php5 extensions:
  ldap mcrypt mysql mysqli pdo pdo_mysql

-- System Information:
Debian Release: 7.2
  APT prefers stable
  APT policy: (500, 'stable')
Architecture: powerpc (ppc)

Kernel: Linux 2.6.32.61
Locale: LANG=C, LC_CTYPE=C (charmap=ANSI_X3.4-1968)
Shell: /bin/sh linked to /bin/dash

Versions of packages apache2 depends on:
ii  apache2-mpm-prefork  2.2.22-13
ii  apache2.2-common     2.2.22-13

apache2 recommends no packages.

apache2 suggests no packages.

Versions of packages apache2.2-common depends on:
ii  apache2-utils  2.2.22-13
ii  apache2.2-bin  2.2.22-13
ii  lsb-base       4.1+Debian8+deb7u1
ii  mime-support   3.52-1
ii  perl           5.14.2-21+deb7u1
ii  procps         1:3.3.3-3

Versions of packages apache2.2-common recommends:
ii  ssl-cert  1.0.32

Versions of packages apache2.2-common suggests:
pn  apache2-doc                             <none>
pn  apache2-suexec | apache2-suexec-custom  <none>
ii  elinks [www-browser]                    0.12~pre5-9
ii  lynx-cur [www-browser]                  2.8.8dev.12-2

-- no debconf information