squid_session causing segmentation fault

[Marcelo Terres]

When I'm using squid_session I'm getting a segmentation fault.

I found the problem in 2 different hardwares, both running Ubuntu 10.04.

Info:

1)root@cache-aca:~# lsb_release -rd
Description: Ubuntu 10.04.2 LTS
Release: 10.04

2)root@cache-aca:~# apt-cache policy squid3
squid3:
  Installed: 3.0.STABLE19-1ubuntu0.1
  Candidate: 3.0.STABLE19-1ubuntu0.1
  Version table:
 *** 3.0.STABLE19-1ubuntu0.1 0
        500 http://security.ubuntu.com/ubuntu/ lucid-security/universe Packages
        100 /var/lib/dpkg/status
     3.0.STABLE19-1 0
        500 http://br.archive.ubuntu.com/ubuntu/ lucid/universe Packages

root@cache-aca:~# /usr/lib/squid3/squid_session -t 100 -b /tmp/testing.db
TESTING
Segmentation fault

root@cache-aca:~# strace /usr/lib/squid3/squid_session -t 100 -b /tmp/testing.db
mprotect(0x601000, 4096, PROT_READ) = 0
mprotect(0x7fe09466c000, 4096, PROT_READ) = 0
munmap(0x7fe094665000, 19023) = 0
set_tid_address(0x7fe0946639d0) = 18808
set_robust_list(0x7fe0946639e0, 0x18) = 0
futex(0x7fff01f755bc, FUTEX_WAKE_PRIVATE, 1) = 0
futex(0x7fff01f755bc, FUTEX_WAIT_BITSET_PRIVATE|FUTEX_CLOCK_REALTIME, 1, NULL, 7fe094663700) = -1 EAGAIN (Resource temporarily unavailable)
rt_sigaction(SIGRTMIN, {0x7fe093b45870, [], SA_RESTORER|SA_SIGINFO, 0x7fe093b4f8f0}, NULL, 8) = 0
rt_sigaction(SIGRT_1, {0x7fe093b45900, [], SA_RESTORER|SA_RESTART|SA_SIGINFO, 0x7fe093b4f8f0}, NULL, 8) = 0
rt_sigprocmask(SIG_UNBLOCK, [RTMIN RT_1], NULL, 8) = 0
getrlimit(RLIMIT_STACK, {rlim_cur=8192*1024, rlim_max=RLIM_INFINITY}) = 0
brk(0) = 0x1923000
brk(0x1944000) = 0x1944000
open("/proc/stat", O_RDONLY|O_CLOEXEC) = 3
read(3, "cpu 4720595 226 3674225 1491889"..., 8192) = 834
close(3) = 0
stat("/tmp/testing.db", {st_mode=S_IFREG|0644, st_size=8192, ...}) = 0
open("/tmp/testing.db", O_RDWR) = 3
fcntl(3, F_GETFD) = 0
fcntl(3, F_SETFD, FD_CLOEXEC) = 0
read(3, "\0\0\0\0\1\0\0\0\0\0\0\0b1\5\0\t\0\0\0\0\20\0\0\0\t\0\0\0\0\0\0"..., 512) = 512
close(3) = 0
open("DB_CONFIG", O_RDONLY) = -1 ENOENT (No such file or directory)
stat("/var/tmp", {st_mode=S_IFDIR|S_ISVTX|0777, st_size=4096, ...}) = 0
gettimeofday({1309809219, 364915}, NULL) = 0
gettimeofday({1309809219, 364978}, NULL) = 0
open("/proc/stat", O_RDONLY|O_CLOEXEC) = 3
read(3, "cpu 4720596 226 3674225 1491889"..., 8192) = 834
close(3) = 0
mmap(NULL, 204800, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fe094630000
open("/tmp/testing.db", O_RDWR|O_CREAT, 0) = 3
fcntl(3, F_GETFD) = 0
fcntl(3, F_SETFD, FD_CLOEXEC) = 0
fstat(3, {st_mode=S_IFREG|0644, st_size=8192, ...}) = 0
pread(3, "\0\0\0\0\1\0\0\0\0\0\0\0b1\5\0\t\0\0\0\0\20\0\0\0\t\0\0\0\0\0\0"..., 4096, 0) = 4096
fstat(0, {st_mode=S_IFCHR|0620, st_rdev=makedev(136, 0), ...}) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fe094669000
read(0, Testing
"Testing\n", 1024) = 8
--- SIGSEGV (Segmentation fault) @ 0 (0) ---
+++ killed by SIGSEGV +++
Segmentation fault

[Amos Jeffries (yadi)]

/tmp is not a safe place to locate an important application data store. Its recommended to use /var/run/squid or /var/cache/squid instead if you require the data to persist long term. If not omit the -b option entirely and the session helper will use a memory cache.

[Roger Millar (rmgomes123)]

I'm getting the same error, too. Even when I omit the "-b" option entirely to force session helper to use a memory cache.

1) LOG in /var/log/messages:
kernel: [695979.392048] squid_session[8400]: segfault at 0 ip b74f0b83 sp bfb61304 error 4 in libc-2.12.1.so[b747c000+157000]

2) root@rogerhost:~#/usr/lib/squid3$ lsb_release -rd
Description: Ubuntu 10.10
Release: 10.10

3) root@rogerhost:~# apt-cache policy squid3
squid3:
  Instalado: 3.1.6-1.1ubuntu1.1
  Candidato: 3.1.6-1.1ubuntu1.1
  Tabela de versão:
 *** 3.1.6-1.1ubuntu1.1 0
        500 http://br.archive.ubuntu.com/ubuntu/ maverick-updates/universe i386 Packages
        500 http://security.ubuntu.com/ubuntu/ maverick-security/universe i386 Packages
        100 /var/lib/dpkg/status
     3.1.6-1.1ubuntu1 0
        500 http://br.archive.ubuntu.com/ubuntu/ maverick/universe i386 Packages

4)root@rogerhost:/usr/lib/squid3# strace ./squid_session -t 3600
execve("./squid_session", ["./squid_session", "-t", "3600"], [/* 20 vars */]) = 0
brk(0) = 0x93d4000
access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
mmap2(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb77d2000
access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY) = 3
fstat64(3, {st_mode=S_IFREG|0644, st_size=86399, ...}) = 0
mmap2(NULL, 86399, PROT_READ, MAP_PRIVATE, 3, 0) = 0xb77bc000
close(3) = 0
access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
open("/usr/lib/libdb-4.8.so", O_RDONLY) = 3
read(3, "\177ELF\1\1\1\0\0\0\0\0\0\0\0\0\3\0\3\0\1\0\0\0pM\1\0004\0\0\0"..., 512) = 512
fstat64(3, {st_mode=S_IFREG|0644, st_size=1443868, ...}) = 0
mmap2(NULL, 1446608, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x9ef000
mmap2(0xb4e000, 12288, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x15e) = 0xb4e000
close(3) = 0
access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
open("/lib/libc.so.6", O_RDONLY) = 3
read(3, "\177ELF\1\1\1\0\0\0\0\0\0\0\0\0\3\0\3\0\1\0\0\0@n\1\0004\0\0\0"..., 512) = 512
fstat64(3, {st_mode=S_IFREG|0755, st_size=1421892, ...}) = 0
mmap2(NULL, 1427880, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x110000
mmap2(0x267000, 12288, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x157) = 0x267000
mmap2(0x26a000, 10664, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x26a000
close(3) = 0
access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
open("/lib/libpthread.so.0", O_RDONLY) = 3
read(3, "\177ELF\1\1\1\0\0\0\0\0\0\0\0\0\3\0\3\0\1\0\0\0\360L\0\0004\0\0\0"..., 512) = 512
fstat64(3, {st_mode=S_IFREG|0755, st_size=121578, ...}) = 0
mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb77bb000
mmap2(NULL, 102920, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x2d6000
mprotect(0x2eb000, 4096, PROT_NONE) = 0
mmap2(0x2ec000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x15...

[Tiago Stürmer Daitx (tdaitx)]

This seems to have been fixed in an earlier squid release.