Bug#609786: libc6: getaddrinfo() incorrectly handles nss failures
Package: libc6
Version: 2.7-18lenny6
Severity: important
Hello,
On a 64-bit system, using 32-bit programs that uses getaddrinfo to resolve dns names will fail in default configuration.
this is caused by an incorrect handling of nss errors.
The delfault nsswitch.conf for host is: files mdns4_minimal [NOTFOUND=return] dns mdns4
But libnss_mdns4_minimal.so.2 is not included in ia32-libs, so getaddrinfo cannot load it (see strace log below).
This would not be an serious problem if it did not return a NOTFOUND instead of an UNAVAIL, (as the service is unavailable, and you cannot say if the record exists or not). UNAVAIL has a 'continue' default action, but NOTFOUND has a 'return' one ; so getaddrinfo() returns with a 'Name or service not known'
Setting NOTFOUND to its default 'continue' action allows getaddrinfo() to fallback to dns methods, and effectively resolving name.
- I think returning NOTFOUND when you cannot load the nss library is an error (UNAVAIL should be better)
- ia32-libs should include libnss_mdns4_minimal.so.2, as mdns_minimal is configured by default
Thanks,
Bastien Durel
-- System Information:
Debian Release: 5.0.7
APT prefers stable
APT policy: (500, 'stable')
Architecture: amd64 (x86_64)
Kernel: Linux 2.6.32.3-grsec-ipsec-std-ipv6-64 (SMP w/2 CPU cores)
Locale: LANG=fr_FR.UTF-8, LC_CTYPE=fr_FR.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/bash
Versions of packages libc6 depends on:
ii libgcc1 1:4.3.2-1.1 GCC support library
libc6 recommends no packages.
Versions of packages libc6 suggests:
pn glibc-doc <none> (no description available)
ii locales 2.7-18lenny6 GNU C Library: National Language (
-- debconf information excluded
me@me-mdh-prod:/tmp$ strace ./test.32
execve("./test.exe", ["./test.exe"], [/* 18 vars */]) = 0
[ Process PID=21581 runs in 32 bit mode. ]
brk(0) = 0x95f4000
access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
mmap2(NULL, 12288, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xfffffffff77a1000
access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
open("/usr/local/pgsql/lib/tls/i686/sse2/cmov/libc.so.6", O_RDONLY) = -1 ENOENT (No such file or directory)
stat64("/usr/local/pgsql/lib/tls/i686/sse2/cmov", 0xff8c32cc) = -1 ENOENT (No such file or directory)
open("/usr/local/pgsql/lib/tls/i686/sse2/libc.so.6", O_RDONLY) = -1 ENOENT (No such file or directory)
stat64("/usr/local/pgsql/lib/tls/i686/sse2", 0xff8c32cc) = -1 ENOENT (No such file or directory)
open("/usr/local/pgsql/lib/tls/i686/cmov/libc.so.6", O_RDONLY) = -1 ENOENT (No such file or directory)
stat64("/usr/local/pgsql/lib/tls/i686/cmov", 0xff8c32cc) = -1 ENOENT (No such file or directory)
open("/usr/local/pgsql/lib/tls/i686/libc.so.6", O_RDONLY) = -1 ENOENT (No such file or directory)
stat64("/usr/local/pgsql/lib/tls/i686", 0xff8c32cc) = -1 ENOENT (No such file or directory)
open("/usr/local/pgsql/lib/tls/sse2/cmov/libc.so.6", O_RDONLY) = -1 ENOENT (No such file or directory)
stat64("/usr/local/pgsql/lib/tls/sse2/cmov", 0xff8c32cc) = -1 ENOENT (No such file or directory)
open("/usr/local/pgsql/lib/tls/sse2/libc.so.6", O_RDONLY) = -1 ENOENT (No such file or directory)
stat64("/usr/local/pgsql/lib/tls/sse2", 0xff8c32cc) = -1 ENOENT (No such file or directory)
open("/usr/local/pgsql/lib/tls/cmov/libc.so.6", O_RDONLY) = -1 ENOENT (No such file or directory)
stat64("/usr/local/pgsql/lib/tls/cmov", 0xff8c32cc) = -1 ENOENT (No such file or directory)
open("/usr/local/pgsql/lib/tls/libc.so.6", O_RDONLY) = -1 ENOENT (No such file or directory)
stat64("/usr/local/pgsql/lib/tls", 0xff8c32cc) = -1 ENOENT (No such file or directory)
open("/usr/local/pgsql/lib/i686/sse2/cmov/libc.so.6", O_RDONLY) = -1 ENOENT (No such file or directory)
stat64("/usr/local/pgsql/lib/i686/sse2/cmov", 0xff8c32cc) = -1 ENOENT (No such file or directory)
open("/usr/local/pgsql/lib/i686/sse2/libc.so.6", O_RDONLY) = -1 ENOENT (No such file or directory)
stat64("/usr/local/pgsql/lib/i686/sse2", 0xff8c32cc) = -1 ENOENT (No such file or directory)
open("/usr/local/pgsql/lib/i686/cmov/libc.so.6", O_RDONLY) = -1 ENOENT (No such file or directory)
stat64("/usr/local/pgsql/lib/i686/cmov", 0xff8c32cc) = -1 ENOENT (No such file or directory)
open("/usr/local/pgsql/lib/i686/libc.so.6", O_RDONLY) = -1 ENOENT (No such file or directory)
stat64("/usr/local/pgsql/lib/i686", 0xff8c32cc) = -1 ENOENT (No such file or directory)
open("/usr/local/pgsql/lib/sse2/cmov/libc.so.6", O_RDONLY) = -1 ENOENT (No such file or directory)
stat64("/usr/local/pgsql/lib/sse2/cmov", 0xff8c32cc) = -1 ENOENT (No such file or directory)
open("/usr/local/pgsql/lib/sse2/libc.so.6", O_RDONLY) = -1 ENOENT (No such file or directory)
stat64("/usr/local/pgsql/lib/sse2", 0xff8c32cc) = -1 ENOENT (No such file or directory)
open("/usr/local/pgsql/lib/cmov/libc.so.6", O_RDONLY) = -1 ENOENT (No such file or directory)
stat64("/usr/local/pgsql/lib/cmov", 0xff8c32cc) = -1 ENOENT (No such file or directory)
open("/usr/local/pgsql/lib/libc.so.6", O_RDONLY) = -1 ENOENT (No such file or directory)
stat64("/usr/local/pgsql/lib", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
open("/etc/ld.so.cache", O_RDONLY) = 3
fstat64(3, {st_mode=S_IFREG|0644, st_size=65758, ...}) = 0
mmap2(NULL, 65758, PROT_READ, MAP_PRIVATE, 3, 0) = 0xfffffffff7790000
close(3) = 0
access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
open("/lib32/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^e\1\0004\0\0\0t"..., 512) = 512
fstat64(3, {st_mode=S_IFREG|0755, st_size=1376492, ...}) = 0
mmap2(NULL, 1382000, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0xfffffffff763e000, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xfffffffff77a0000
read(3, "127.0.0.1\tlocalhost\n10.100.0.184\t"..., 4096) = 298
read(3, ""..., 4096) = 0
close(3) = 0
munmap(0xf77a0000, 4096) = 0
open("/etc/hosts", O_RDONLY|O_CLOEXEC) = 3
fstat64(3, {st_mode=S_IFREG|0644, st_size=298, ...}) = 0
mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xfffffffff77a0000
read(3, "127.0.0.1\tlocalhost\n10.100.0.184\t"..., 4096) = 298
read(3, ""..., 4096) = 0
close(3) = 0
munmap(0xf77a0000, 4096) = 0
open("/usr/local/pgsql/lib/libnss_mdns4_minimal.so.2", O_RDONLY) = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY) = 3
fstat64(3, {st_mode=S_IFREG|0644, st_size=65758, ...}) = 0
mmap2(NULL, 65758, PROT_READ, MAP_PRIVATE, 3, 0) = 0xfffffffff7790000
close(3) or directory)
stat64("/emul/ia32-linux/lib/cmov", 0xff8c2c00) = -1 ENOENT (No such file or directory)
open("/emul/ia32-linux/lib/libnss_mdns4_minimal.so.2", O_RDONLY) = -1 ENOENT (No such file or directory)
stat64("/emul/ia32-linux/lib", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
open("/emul/ia32-linux/usr/lib/tls/i686/sse2/cmov/libnss_mdns4_minimal.so.2", O_RDONLY) = -1 ENOENT (No such file or directory)
stat64("/emul/ia32-linux/usr/lib/tls/i686/sse2/cmov", 0xff8c2c00) = -1 ENOENT (No such file or directory)
open("/emul/ia32-linux/usr/lib/tls/i686/sse2/libnss_mdns4_minimal.so.2", O_RDONLY) = -1 ENOENT (No such file or directory)
stat64("/emul/ia32-linux/usr/lib/tls/i686/sse2", 0xff8c2c00) = -1 ENOENT (No such file or directory)
open("/emul/ia32-linux/usr/lib/tls/i686/cmov/libnss_mdns4_minimal.so.2", O_RDONLY) = -1 ENOENT (No such file or directory)
stat64("/emul/ia32-linux/usr/lib/tls/i686/cmov", 0xff8c2c00) = -1 ENOENT (No such file or directory)
open("/emul/ia32-linux/usr/lib/tls/i686/libnss_mdns4_minimal.so.2", O_RDONLY) = -1 ENOENT (No such file or directory)
stat64("/emul/ia32-linux/usr/lib/tls/i686", 0xff8c2c00) = -1 ENOENT (No such file or directory)
open("/emul/ia32-linux/usr/lib/tls/sse2/cmov/libnss_mdns4_minimal.so.2", O_RDONLY) = -1 ENOENT (No such file or directory)
stat64("/emul/ia32-linux/usr/lib/tls/sse2/cmov", 0xff8c2c00) = -1 ENOENT (No such file or directory)
open("/emul/ia32-linux/usr/lib/tls/sse2/libnss_mdns4_minimal.so.2", O_RDONLY) = -1 ENOENT (No such file or directory)
stat64("/emul/ia32-linux/usr/lib/tls/sse2", 0xff8c2c00) = -1 ENOENT (No such file or directory)
open("/emul/ia32-linux/usr/lib/tls/cmov/libnss_mdns4_minimal.so.2", O_RDONLY) = -1 ENOENT (No such file or directory)
stat64("/emul/ia32-linux/usr/lib/tls/cmov", 0xff8c2c00) = -1 ENOENT (No such file or directory)
open("/emul/ia32-linux/usr/lib/tls/libnss_mdns4_minimal.so.2", O_RDONLY) = -1 ENOENT (No such file or directory)
stat64("/emul/ia32-linux/usr/lib/tls", 0xff8c2c00) = -1 ENOENT (No such file or directory)
open("/emul/ia32-linux/usr/lib/i686/sse2/cmov/libnss_mdns4_minimal.so.2", O_RDONLY) = -1 ENOENT (No such file or directory)
stat64("/emul/ia32-linux/usr/lib/i686/sse2/cmov", 0xff8c2c00) = -1 ENOENT (No such file or directory)
open("/emul/ia32-linux/usr/lib/i686/sse2/libnss_mdns4_minimal.so.2", O_RDONLY) = -1 ENOENT (No such file or directory)
stat64("/emul/ia32-linux/usr/lib/i686/sse2", 0xff8c2c00) = -1 ENOENT (No such file or directory)
open("/emul/ia32-linux/usr/lib/i686/cmov/libnss_mdns4_minimal.so.2", O_RDONLY) = -1 ENOENT (No such file or directory)
stat64("/emul/ia32-linux/usr/lib/i686/cmov", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
open("/emul/ia32-linux/usr/lib/i686/libnss_mdns4_minimal.so.2", O_RDONLY) = -1 ENOENT (No such file or directory)
stat64("/emul/ia32-linux/usr/lib/i686", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
open("/usr/lib/i486-linux-gnu/sse2/cmov/libnss_mdns4_minimal.so.2", O_RDONLY) = -1 ENOENT (No such file or directory)
stat64("/usr/lib/i486-linux-gnu/sse2/cmov", 0xff8c2c00) = -1 ENOENT (No such file or directory)
open("/usr/lib/i486-linux-gnu/sse2/libnss_mdns4_minimal.so.2", O_RDONLY) = -1 ENOENT (No such file or directory)
stat64("/usr/lib/i486-linux-gnu/sse2", 0xff8c2c00) = -1 ENOENT (No such file or directory)
open("/usr/lib/i486-linux-gnu/cmov/libnss_mdns4_minimal.so.2", O_RDONLY) = -1 ENOENT (No such file or directory)
stat64("/usr/lib/i486-linux-gnu/cmov", 0xff8c2c00) = -1 ENOENT (No such file or directory)
open("/usr/lib/i486-linux-gnu/libnss_mdns4_minimal.so.2", O_RDONLY) = -1 ENOENT (No such file or directory)
stat64("/usr/lib/i486-linux-gnu", 0xff8c2c00) = -1 ENOENT (No such file or directory)
munmap(0xf7790000, 65758) = 0
write(2, "error in getaddrinfo: Name or ser"..., 48error in getaddrinfo: Name or service not known
) = 48
exit_group(1) = ?
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