Previously, we allocated room in the result space before the check,
leaving uninitialized data there in case the check failed.
This also consolidates the behavior between single (A or AAAA) and
dual (A and AAAA in parallel) queries. Single queries checked
the record length against the QTYPE, not the RRTYPE.
In various error scenarios (for example, if the server closes the
TCP connection before sending the full response), send_vc can return
without resetting the *resplen2 value. This can pass uninitialized
or unexpected data to the caller.
Since commit 44d20bca52 (Implement
second fallback mode for DNS requests), there is a code path which
returns early, before *resplen2 is initialized. This happens if the
name server address is immediately recognized as invalid (because of
lack of protocol support, or if it is a broadcast address such
255.255.255.255, or another invalid address).
If this happens and *resplen2 was non-zero (which is the case if a
previous query resulted in a failure), __libc_res_nquery would reuse
an existing second answer buffer. This answer has been previously
identified as unusable (for example, it could be an NXDOMAIN
response). Due to the presence of a second answer, no name server
switching will occur. The result is a name resolution failure,
although a successful resolution would have been possible if name
servers have been switched and queries had proceeded along the search
path.
The above paragraph still simplifies the situation. Before glibc
2.23, if the second answer needed malloc, the stub resolver would
still attempt to reuse the second answer, but this is not possible
because __libc_res_nsearch has freed it, after the unsuccessful call
to __libc_res_nquerydomain, and set the buffer pointer to NULL. This
eventually leads to an assertion failure in __libc_res_nquery:
/* Make sure both hp and hp2 are defined */
assert((hp != NULL) && (hp2 != NULL));
If assertions are disabled, the consequence is a NULL pointer
dereference on the next line.
Starting with glibc 2.23, as a result of commit
e9db92d3ac (CVE-2015-7547: getaddrinfo()
stack-based buffer overflow (Bug 18665)), the second answer is always
allocated with malloc. This means that the assertion failure happens
with small responses as well because there is no buffer to reuse, as
soon as there is a name resolution failure which triggers a search for
an answer along the search path.
This commit addresses the issue by ensuring that *resplen2 is
initialized before the send_dg function returns.
This commit also addresses a bug where an invalid second reply is
incorrectly returned as a valid to the caller.
The number of currently defined nameservers is stored in ->nscount,
whereas ->_u._ext.nscount is set by __libc_res_nsend only after local
initializations.
* A stack-based buffer overflow was found in libresolv when invoked from
libnss_dns, allowing specially crafted DNS responses to seize control
of execution flow in the DNS client. The buffer overflow occurs in
the functions send_dg (send datagram) and send_vc (send TCP) for the
NSS module libnss_dns.so.2 when calling getaddrinfo with AF_UNSPEC
family. The use of AF_UNSPEC triggers the low-level resolver code to
send out two parallel queries for A and AAAA. A mismanagement of the
buffers used for those queries could result in the response of a query
writing beyond the alloca allocated buffer created by
_nss_dns_gethostbyname4_r. Buffer management is simplified to remove
the overflow. Thanks to the Google Security Team and Red Hat for
reporting the security impact of this issue, and Robert Holiday of
Ciena for reporting the related bug 18665. (CVE-2015-7547)
See also:
https://sourceware.org/ml/libc-alpha/2016-02/msg00416.htmlhttps://sourceware.org/ml/libc-alpha/2016-02/msg00418.html
Resetting defdname (default domain name) before use in __res_vinit
ensures that the default domain name is correctly set to a default
value when it is not set by the LOCALDOMAIN environment variable or
the "domain" or "search" parameters in resolv.conf
Tested using the steps from:
https://sourceware.org/bugzilla/show_bug.cgi?id=19369
One common case of __GNUC_PREREQ (4, 7) conditionals is use of
diagnostic control pragmas for -Wmaybe-uninitialized, an option
introduced in GCC 4.7 where older GCC needed -Wuninitialized to be
controlled instead if the warning appeared with older GCC. This patch
removes such conditionals.
(There remain several older uses of -Wno-uninitialized in makefiles
that still need to be converted to diagnostic control pragmas if the
issue is still present with current sources and supported GCC
versions, and it's likely that in most cases those pragmas also will
end up controlling -Wmaybe-uninitialized.)
Tested for x86_64 and x86 (testsuite, and that installed stripped
shared libraries are unchanged by the patch, except for libresolv
since res_send.c contains assertions whose line numbers are changed by
the patch).
* resolv/res_send.c (send_vc) [__GNUC_PREREQ (4, 7)]: Make code
unconditional.
* soft-fp/fmadf4.c [__GNUC_PREREQ (4, 7)]: Likewise.
[!__GNUC_PREREQ (4, 7)]: Remove conditional code.
* soft-fp/fmasf4.c [__GNUC_PREREQ (4, 7)]: Make code
unconditional.
[!__GNUC_PREREQ (4, 7)]: Remove conditional code.
* soft-fp/fmatf4.c [__GNUC_PREREQ (4, 7)]: Make code
unconditional.
[!__GNUC_PREREQ (4, 7)]: Remove conditional code.
* stdlib/setenv.c
[((__GNUC__ << 16) + __GNUC_MINOR__) >= ((4 << 16) + 7)]: Make
code unconditional.
[!(((__GNUC__ << 16) + __GNUC_MINOR__) >= ((4 << 16) + 7))]:
Remove conditional code.
* sysdeps/ieee754/dbl-64/e_lgamma_r.c
(__ieee754_lgamma_r) [__GNUC_PREREQ (4, 7)]: Make code
unconditional.
(__ieee754_lgamma_r) [!__GNUC_PREREQ (4, 7)]: Remove conditional
code.
* sysdeps/ieee754/flt-32/e_lgammaf_r.c
(__ieee754_lgammaf_r) [__GNUC_PREREQ (4, 7)]: Make code
unconditional.
(__ieee754_lgammaf_r) [!__GNUC_PREREQ (4, 7)]: Remove conditional
code.
* sysdeps/ieee754/ldbl-128/k_tanl.c
(__kernel_tanl) [__GNUC_PREREQ (4, 7)]: Make code unconditional.
(__kernel_tanl) [!__GNUC_PREREQ (4, 7)]: Remove conditional code.
* sysdeps/ieee754/ldbl-128ibm/k_tanl.c
(__kernel_tanl) [__GNUC_PREREQ (4, 7)]: Make code unconditional.
(__kernel_tanl) [!__GNUC_PREREQ (4, 7)]: Remove conditional code.
* sysdeps/ieee754/ldbl-96/e_lgammal_r.c
(__ieee754_lgammal_r) [__GNUC_PREREQ (4, 7)]: Make code
unconditional.
(__ieee754_lgammal_r) [!__GNUC_PREREQ (4, 7)]: Remove conditional
code.
* sysdeps/ieee754/ldbl-96/k_tanl.c
(__kernel_tanl) [__GNUC_PREREQ (4, 7)]: Make code unconditional.
(__kernel_tanl) [!__GNUC_PREREQ (4, 7)]: Remove conditional code.
This patch converts a few more function definitions in glibc from
old-style K&R to prototype style. This is sufficient to build and
test on x86_64 and x86 with -Wold-style-definition (I'll test on some
more architectures before proposing the actual addition of
-Wold-style-definition).
Tested for x86_64 and x86 with -Wold-style-definition in use
(testsuite - this patch affects files containing assertions).
* io/fts.c (fts_open): Convert to prototype-style function
definition.
* malloc/mcheck.c (mcheck): Likewise.
(mcheck_pedantic): Likewise.
* posix/regexec.c (re_search_2_stub): Likewise. Use
internal_function.
(re_search_internal): Likewise.
* resolv/res_init.c [RESOLVSORT] (net_mask): Convert to
prototype-style function definition.
* sunrpc/clnt_udp.c (clntudp_call): Likewise.
* sunrpc/pmap_rmt.c (clnt_broadcast): Likewise.
* sunrpc/rpcsvc/rusers.x (xdr_utmp): Likewise.
(xdr_utmpptr): Likewise.
(xdr_utmparr): Likewise.
(xdr_utmpidle): Likewise.
(xdr_utmpidleptr): Likewise.
(xdr_utmpidlearr): Likewise.
This mostly automatically-generated patch converts 113 function
definitions in glibc from old-style K&R to prototype-style. Following
my other recent such patches, this one deals with the case of function
definitions in files that either contain assertions or where grep
suggested they might contain assertions - and thus where it isn't
possible to use a simple object code comparison as a sanity check on
the correctness of the patch, because line numbers are changed.
A few such automatically-generated changes needed to be supplemented
by manual changes for the result to compile. openat64 had a prototype
declaration with "..." but an old-style definition in
sysdeps/unix/sysv/linux/dl-openat64.c, and "..." needed adding to the
generated prototype in the definition (I've filed
<https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68024> for diagnosing
such cases in GCC; the old state was undefined behavior not requiring
a diagnostic, but one seems a good idea). In addition, as Florian has
noted regparm attribute mismatches between declaration and definition
are only diagnosed for prototype definitions, and five functions
needed internal_function added to their definitions (in the case of
__pthread_mutex_cond_lock, via the macro definition of
__pthread_mutex_lock) to compile on i386.
After this patch is in, remaining old-style definitions are probably
most readily fixed manually before we can turn on
-Wold-style-definition for all builds.
Tested for x86_64 and x86 (testsuite).
* crypt/md5-crypt.c (__md5_crypt_r): Convert to prototype-style
function definition.
* crypt/sha256-crypt.c (__sha256_crypt_r): Likewise.
* crypt/sha512-crypt.c (__sha512_crypt_r): Likewise.
* debug/backtracesyms.c (__backtrace_symbols): Likewise.
* elf/dl-minimal.c (_itoa): Likewise.
* hurd/hurdmalloc.c (malloc): Likewise.
(free): Likewise.
(realloc): Likewise.
* inet/inet6_option.c (inet6_option_space): Likewise.
(inet6_option_init): Likewise.
(inet6_option_append): Likewise.
(inet6_option_alloc): Likewise.
(inet6_option_next): Likewise.
(inet6_option_find): Likewise.
* io/ftw.c (FTW_NAME): Likewise.
(NFTW_NAME): Likewise.
(NFTW_NEW_NAME): Likewise.
(NFTW_OLD_NAME): Likewise.
* libio/iofwide.c (_IO_fwide): Likewise.
* libio/strops.c (_IO_str_init_static_internal): Likewise.
(_IO_str_init_static): Likewise.
(_IO_str_init_readonly): Likewise.
(_IO_str_overflow): Likewise.
(_IO_str_underflow): Likewise.
(_IO_str_count): Likewise.
(_IO_str_seekoff): Likewise.
(_IO_str_pbackfail): Likewise.
(_IO_str_finish): Likewise.
* libio/wstrops.c (_IO_wstr_init_static): Likewise.
(_IO_wstr_overflow): Likewise.
(_IO_wstr_underflow): Likewise.
(_IO_wstr_count): Likewise.
(_IO_wstr_seekoff): Likewise.
(_IO_wstr_pbackfail): Likewise.
(_IO_wstr_finish): Likewise.
* locale/programs/localedef.c (normalize_codeset): Likewise.
* locale/programs/locarchive.c (add_locale_to_archive): Likewise.
(add_locales_to_archive): Likewise.
(delete_locales_from_archive): Likewise.
* malloc/malloc.c (__libc_mallinfo): Likewise.
* math/gen-auto-libm-tests.c (init_fp_formats): Likewise.
* misc/tsearch.c (__tfind): Likewise.
* nptl/pthread_attr_destroy.c (__pthread_attr_destroy): Likewise.
* nptl/pthread_attr_getdetachstate.c
(__pthread_attr_getdetachstate): Likewise.
* nptl/pthread_attr_getguardsize.c (pthread_attr_getguardsize):
Likewise.
* nptl/pthread_attr_getinheritsched.c
(__pthread_attr_getinheritsched): Likewise.
* nptl/pthread_attr_getschedparam.c
(__pthread_attr_getschedparam): Likewise.
* nptl/pthread_attr_getschedpolicy.c
(__pthread_attr_getschedpolicy): Likewise.
* nptl/pthread_attr_getscope.c (__pthread_attr_getscope):
Likewise.
* nptl/pthread_attr_getstack.c (__pthread_attr_getstack):
Likewise.
* nptl/pthread_attr_getstackaddr.c (__pthread_attr_getstackaddr):
Likewise.
* nptl/pthread_attr_getstacksize.c (__pthread_attr_getstacksize):
Likewise.
* nptl/pthread_attr_init.c (__pthread_attr_init_2_1): Likewise.
(__pthread_attr_init_2_0): Likewise.
* nptl/pthread_attr_setdetachstate.c
(__pthread_attr_setdetachstate): Likewise.
* nptl/pthread_attr_setguardsize.c (pthread_attr_setguardsize):
Likewise.
* nptl/pthread_attr_setinheritsched.c
(__pthread_attr_setinheritsched): Likewise.
* nptl/pthread_attr_setschedparam.c
(__pthread_attr_setschedparam): Likewise.
* nptl/pthread_attr_setschedpolicy.c
(__pthread_attr_setschedpolicy): Likewise.
* nptl/pthread_attr_setscope.c (__pthread_attr_setscope):
Likewise.
* nptl/pthread_attr_setstack.c (__pthread_attr_setstack):
Likewise.
* nptl/pthread_attr_setstackaddr.c (__pthread_attr_setstackaddr):
Likewise.
* nptl/pthread_attr_setstacksize.c (__pthread_attr_setstacksize):
Likewise.
* nptl/pthread_condattr_setclock.c (pthread_condattr_setclock):
Likewise.
* nptl/pthread_create.c (__find_in_stack_list): Likewise.
* nptl/pthread_getattr_np.c (pthread_getattr_np): Likewise.
* nptl/pthread_mutex_cond_lock.c (__pthread_mutex_lock): Define to
use internal_function.
* nptl/pthread_mutex_init.c (__pthread_mutex_init): Convert to
prototype-style function definition.
* nptl/pthread_mutex_lock.c (__pthread_mutex_lock): Likewise.
(__pthread_mutex_cond_lock_adjust): Likewise. Use
internal_function.
* nptl/pthread_mutex_timedlock.c (pthread_mutex_timedlock):
Convert to prototype-style function definition.
* nptl/pthread_mutex_trylock.c (__pthread_mutex_trylock):
Likewise.
* nptl/pthread_mutex_unlock.c (__pthread_mutex_unlock_usercnt):
Likewise.
(__pthread_mutex_unlock): Likewise.
* nptl_db/td_ta_clear_event.c (td_ta_clear_event): Likewise.
* nptl_db/td_ta_set_event.c (td_ta_set_event): Likewise.
* nptl_db/td_thr_clear_event.c (td_thr_clear_event): Likewise.
* nptl_db/td_thr_event_enable.c (td_thr_event_enable): Likewise.
* nptl_db/td_thr_set_event.c (td_thr_set_event): Likewise.
* nss/makedb.c (process_input): Likewise.
* posix/fnmatch.c (__strchrnul): Likewise.
(__wcschrnul): Likewise.
(fnmatch): Likewise.
* posix/fnmatch_loop.c (FCT): Likewise.
* posix/glob.c (globfree): Likewise.
(__glob_pattern_type): Likewise.
(__glob_pattern_p): Likewise.
* posix/regcomp.c (re_compile_pattern): Likewise.
(re_set_syntax): Likewise.
(re_compile_fastmap): Likewise.
(regcomp): Likewise.
(regerror): Likewise.
(regfree): Likewise.
* posix/regexec.c (regexec): Likewise.
(re_match): Likewise.
(re_search): Likewise.
(re_match_2): Likewise.
(re_search_2): Likewise.
(re_search_stub): Likewise. Use internal_function
(re_copy_regs): Likewise.
(re_set_registers): Convert to prototype-style function
definition.
(prune_impossible_nodes): Likewise. Use internal_function.
* resolv/inet_net_pton.c (inet_net_pton): Convert to
prototype-style function definition.
(inet_net_pton_ipv4): Likewise.
* stdlib/strtod_l.c (____STRTOF_INTERNAL): Likewise.
* sysdeps/pthread/aio_cancel.c (aio_cancel): Likewise.
* sysdeps/pthread/aio_suspend.c (aio_suspend): Likewise.
* sysdeps/pthread/timer_delete.c (timer_delete): Likewise.
* sysdeps/unix/sysv/linux/dl-openat64.c (openat64): Likewise.
Make variadic.
* time/strptime_l.c (localtime_r): Convert to prototype-style
function definition.
* wcsmbs/mbsnrtowcs.c (__mbsnrtowcs): Likewise.
* wcsmbs/mbsrtowcs_l.c (__mbsrtowcs_l): Likewise.
* wcsmbs/wcsnrtombs.c (__wcsnrtombs): Likewise.
* wcsmbs/wcsrtombs.c (__wcsrtombs): Likewise.
This automatically-generated patch converts 29 function definitions in
glibc (including one in an example in the manual) from old-style K&R
to prototype-style. Following my other recent such patches, this one
deals with the case of function definitions where one K&R parameter
declaration declares multiple parameters, as in:
void
foo (a, b)
int a, *b;
{
}
Tested for x86_64 and x86 (testsuite, and that installed stripped
shared libraries are unchanged by the patch).
* crypt/crypt.c (_ufc_doit_r): Convert to prototype-style function
definition.
(_ufc_doit_r): Likewise.
* crypt/crypt_util.c (_ufc_copymem): Likewise.
(_ufc_output_conversion_r): Likewise.
* inet/inet_mkadr.c (__inet_makeaddr): Likewise.
* inet/rcmd.c (rcmd_af): Likewise.
(rcmd): Likewise.
(ruserok_af): Likewise.
(ruserok): Likewise.
(ruserok2_sa): Likewise.
(ruserok_sa): Likewise.
(iruserok_af): Likewise.
(iruserok): Likewise.
(__ivaliduser): Likewise.
(__validuser2_sa): Likewise.
* inet/rexec.c (rexec_af): Likewise.
(rexec): Likewise.
* inet/ruserpass.c (ruserpass): Likewise.
* locale/programs/xmalloc.c (xcalloc): Likewise.
* manual/examples/timeval_subtract.c (timeval_subtract): Likewise.
* math/w_drem.c (__drem): Likewise.
* math/w_dremf.c (__dremf): Likewise.
* math/w_dreml.c (__dreml): Likewise.
* misc/daemon.c (daemon): Likewise.
* resolv/res_debug.c (p_fqnname): Likewise.
* stdlib/div.c (div): Likewise.
* string/memcmp.c (memcmp_bytes): Likewise.
* sunrpc/pmap_rmt.c (pmap_rmtcall): Likewise.
* sunrpc/svc_udp.c (svcudp_bufcreate): Likewise.
Two glibc makefiles use -Wno-strict-prototypes. I don't know if this
was needed before my recent conversion of many function definitions to
prototype style, but it's not needed now; this patch removes it.
Tested for x86_64 and x86 (testsuite, and that installed stripped
shared libraries are unchanged by the patch).
* posix/Makefile (CFLAGS-regex.c): Remove variable.
* resolv/Makefile (+cflags): Do not use -Wno-strict-prototypes.
With gcc-4.9, a new -fstack-protector-strong flag is available that is
between -fstack-protector (pretty weak) and -fstack-protector-all (pretty
strong) that provides good trade-offs between overhead but still providing
good coverage. Update the places in glibc that use ssp to use this flag
when it's available.
This also kills off the indirection of hardcoding the flag name in the
Makefiles and adding it based on a have-ssp boolean. Instead, the build
always expands the $(stack-protector) variable to the best ssp setting.
This makes the build logic a bit simpler and allows people to easily set
to a diff flag like:
make stack-protector=-fstack-protector-all
These tests were skipped by the use-test-skeleton conversion done in
commit 29955b5d because they did not have an `int main (void)'
declaration. Instead their `main' functions were declared with arguments
(i.e. argc, argv) even though they didn't use them.
Remove these arguments and include the test skeleton in these tests.
When "reorder" resolver option is enabled, threads of a multi-threaded process
could hang in gethostbyaddr_r, gethostbyname_r, or gethostbyname2_r.
Due to a trivial bug in _res_hconf_reorder_addrs, simultaneous
invocations of this function in a multi-threaded process could result to
_res_hconf_reorder_addrs returning without releasing the lock it holds,
causing other threads to block indefinitely while waiting for the lock
that is not going to be released.
[BZ #17977]
* resolv/res_hconf.c (_res_hconf_reorder_addrs): Fix unlocking
when initializing interface list, based on the bug analysis
and the patch proposed by Eric Newton.
* resolv/tst-res_hconf_reorder.c: New test.
* resolv/Makefile [$(have-thread-library) = yes] (tests): Add
tst-res_hconf_reorder.
($(objpfx)tst-res_hconf_reorder): Depend on $(libdl)
and $(shared-thread-library).
(tst-res_hconf_reorder-ENV): New variable.
netdb.h declares interfaces such as getaddrinfo if __USE_POSIX,
i.e. POSIX.1:1990 or later. However, these interfaces were new in the
2001 edition of POSIX, although the header was in XPG4 and UNIX98, so
they should not be declared for XPG4 or UNIX98. (This produces
spurious linknamespace test failures, although there are other
failures for this header as well for the same standards so this patch
doesn't remove any XFAILs.) This patch corrects the condition, and
the conform/ test expectations which were similarly wrong.
Tested for x86_64 and x86 (testsuite, and that installed stripped
shared libraries are unchanged by the patch).
[BZ #18529]
* resolv/netdb.h [__USE_POSIX]: Change condition to
[__USE_XOPEN2K].
* conform/data/netdb.h-data [XPG4 || UNIX98] (struct addrinfo): Do
not expect.
[XPG4 || UNIX98] (AI_PASSIVE): Likewise.
[XPG4 || UNIX98] (AI_CANONNAME): Likewise.
[XPG4 || UNIX98] (AI_NUMERICHOST): Likewise.
[XPG4 || UNIX98] (AI_V4MAPPED): Likewise.
[XPG4 || UNIX98] (AI_ALL): Likewise.
[XPG4 || UNIX98] (AI_ADDRCONFIG): Likewise.
[XPG4 || UNIX98] (AI_NUMERICSERV): Likewise.
[XPG4 || UNIX98] (NI_NOFQDN): Likewise.
[XPG4 || UNIX98] (NI_NUMERICHOST): Likewise.
[XPG4 || UNIX98] (NI_NAMEREQD): Likewise.
[XPG4 || UNIX98] (NI_NUMERICSERV): Likewise.
[XPG4 || UNIX98] (NI_DGRAM): Likewise.
[XPG4 || UNIX98] (EAI_AGAIN): Likewise.
[XPG4 || UNIX98] (EAI_BADFLAGS): Likewise.
[XPG4 || UNIX98] (EAI_FAIL): Likewise.
[XPG4 || UNIX98] (EAI_FAMILY): Likewise.
[XPG4 || UNIX98] (EAI_MEMORY): Likewise.
[XPG4 || UNIX98] (EAI_NONAME): Likewise.
[XPG4 || UNIX98] (EAI_SERVICE): Likewise.
[XPG4 || UNIX98] (EAI_SOCKTYPE): Likewise.
[XPG4 || UNIX98] (EAI_SYSTEM): Likewise.
[XPG4 || UNIX98] (EAI_SYSTEM): Likewise.
[XPG4 || UNIX98] (freeaddrinfo): Likewise.
[XPG4 || UNIX98] (gai_strerror): Likewise.
[XPG4 || UNIX98] (getaddrinfo): Likewise.
[XPG4 || UNIX98] (getnameinfo): Likewise.
The 2008 edition of POSIX removed h_errno, but some functions still
bring in references to the h_errno external symbol. As this symbol is
not a part of the public ABI (only __h_errno_location is), this patch
fixes this by renaming the GLIBC_PRIVATE TLS symbol to __h_errno.
Tested for x86_64 and x86 (testsuite, and comparison of installed
shared libraries). Disassembly of all shared libraries using h_errno
changes because of the renaming (and changes to associated TLS / GOT
offsets in some cases); disassembly of libpthread on x86_64 changes
more substantially because the enlargement of .dynsym affects
subsequent addresses.
[BZ #18520]
* inet/herrno.c (h_errno): Rename to __h_errno.
(__libc_h_errno): Define as alias of __h_errno not h_errno.
* include/netdb.h [IS_IN_LIB && !IS_IN (libc)] (h_errno): Define
to __h_errno instead of h_errno.
* nptl/herrno.c (h_errno): Rename to __h_errno.
(__h_errno_location): Refer to __h_errno not h_errno.
* resolv/Versions (h_errno): Rename to __h_errno.
* conform/Makefile (test-xfail-XOPEN2K8/grp.h/linknamespace):
Remove variable.
(test-xfail-XOPEN2K8/pwd.h/linknamespace): Likewise.
Remove use of ext.nsmap member of struct __res_state and always use
an identity mapping betwen the nsaddr_list array and the ext.nsaddrs
array. The fact that a nameserver has an IPv6 address is signalled by
setting nsaddr_list[].sin_family to zero.
DNSSEC defines a number of response types that one me expect when the
DO bit is set. We don't process any of them, but since we do allow
setting the DO bit, skip them without logging an error since it is
only a nuisance.
Tested on x86_64.
[BZ #14841]
* resolv/gethnamaddr.c (getanswer): Skip logging if
RES_USE_DNSSEC is set.
* resolv/nss_dns/dns-host.c (getanswer_r): Likewise.
The rotate option doesn't work correctly, and only send the query to the
same server (the second in the list). The rotation code in itself is not
broken, but the nsaddrs structure is reinitialized each time at the
beginning of __libc_res_nsend unless RES_STAYOPEN is enabled.
This is due to a call to __res_iclose from the end of __libc_res_nsend
when answers from the name server have been received. This function
closes all the sockets, but doesn't free the addresses (it can do that,
but in that case the second argument is false).
This patch change the code of __res_iclose to clear statp->_u._ext.nsinit
only when the addresses are actually freed.
* resolv/res_init.c (__res_iclose): Only clear nsinit if the
addresses have been freed.
The current comments concerning nserv and nservall are not really clear
and lead to confusion when reviewing an already complex code. Improve
them, there real meaning have been confirmed by a code analysis.
* resolv/res_init.c (__res_vinit): Improve comments about nserv
and nservall.
Parts of the resolver brought in by pthreads (at least) use inet_*
functions that aren't in the 1995/6 edition of POSIX that introduced
pthreads (or in one case, use __inet_aton which is then defined in the
same file as non-weak inet_addr). This patch fixes this by making the
affected functions into weak alias for __inet_* and using those names
in the problematic resolver code.
Tested for x86_64 (testsuite, and that disassembly of installed shared
libraries is unchanged by the patch).
[BZ #17722]
* inet/inet_mkadr.c (inet_makeaddr): Rename to __inet_makeaddr and
define as weak alias of __inet_makeaddr.
* resolv/inet_addr.c (inet_addr): Rename to __inet_addr and define
as weak alias of __inet_addr.
* resolv/inet_pton.c (inet_pton): Rename to __inet_pton and define
as weak alias of __inet_pton. Use libc_hidden_weak.
* include/arpa/inet.h (__inet_pton): Declare. Use
libc_hidden_proto.
(inet_makeaddr): Don't use libc_hidden_proto.
(__inet_makeaddr): Declare. Use libc_hidden_proto.
* resolv/res_init.c (__res_vinit): Use __inet_pton instead of
inet_pton. Use __inet_makeaddr instead of inet_makeaddr.
* conform/Makefile (test-xfail-POSIX/pthread.h/linknamespace):
Remove variable.
(test-xfail-POSIX/sched.h/linknamespace): Likewise.
(test-xfail-POSIX/time.h/linknamespace): Likewise.
Resolver code, brought in by pthreads (at least), uses if_* interfaces
that weren't in POSIX before 2001, resulting in linknamespace
failures. This patch changes those interfaces to be weak aliases of
__if_* and makes the resolver use __if_* directly.
Tested for x86_64 (testsuite, and that disassembly of installed shared
libraries is unchanged by this patch).
[BZ #17717]
* inet/if_index.c (if_nametoindex): Rename to __if_nametoindex and
define as weak alias of __if_nametoindex. Use libc_hidden_weak.
(if_indextoname): Rename to __if_indextoname and define as weak
alias of __if_indextoname. Use libc_hidden_weak.
(if_freenameindex): Rename to __if_freenameindex and define as
weak alias of __if_freenameindex.
(if_nameindex): Rename to __if_nameindex and define as weak alias
of __if_nameindex.
* sysdeps/mach/hurd/if_index.c (if_nametoindex): Rename to
__if_nametoindex and define as weak alias of __if_nametoindex.
Use libc_hidden_weak.
(if_freenameindex): Rename to __if_freenameindex and define as
weak alias of __if_freenameindex.
(if_nameindex): Rename to __if_nameindex and define as weak alias
of __if_nameindex.
(if_indextoname): Rename to __if_indextoname and define as weak
alias of __if_indextoname. Use libc_hidden_weak.
* sysdeps/unix/sysv/linux/if_index.c (if_nametoindex): Rename to
__if_nametoindex and define as weak alias of __if_nametoindex.
Use libc_hidden_weak.
(if_freenameindex): Rename to __if_freenameindex and define as
weak alias of __if_freenameindex. Use libc_hidden_weak.
(if_nameindex_netlink): Use __if_freenameindex instead of
if_freenameindex.
(if_nameindex): Rename to __if_nameindex and define as weak alias
of __if_nameindex. Use libc_hidden_weak.
(if_indextoname): Rename to __if_indextoname and define as weak
alias of __if_indextoname. Use libc_hidden_weak.
* include/net/if.h [!_ISOMAC] (__if_nametoindex): Declare and use
libc_hidden_proto.
[!_ISOMAC] (__if_freenameindex): Likewise.
* resolv/res_init.c (__res_vinit): Use __if_nametoindex instead of
if_nametoindex.
* conform/Makefile (test-xfail-XPG4/grp.h/linknamespace): Remove
variable.
(test-xfail-XPG4/pwd.h/linknamespace): Likewise.
(test-xfail-UNIX98/aio.h/linknamespace): Likewise.
(test-xfail-UNIX98/grp.h/linknamespace): Likewise.
(test-xfail-UNIX98/pthread.h/linknamespace): Likewise.
(test-xfail-UNIX98/pwd.h/linknamespace): Likewise.
(test-xfail-UNIX98/sched.h/linknamespace): Likewise.
(test-xfail-UNIX98/time.h/linknamespace): Likewise.
I see this warning in my build on F21 x86_64, which seems to be due to
a weak check for array bounds. Fixed by making the bounds check
stronger.
This is not an actual bug since nscount is never set to anything
greater than MAXNS. The compiler however does not know this, so we
need the stronger bounds check to quieten the compiler.
In send_vc function at resolv/res_send.c, There is the
following warning on some architectures:
'resplen' may be used uninitialized in this function
[-Wmaybe-uninitialized]
And this is a false positive. This patch suppress the
compiler warning.
Various POSIX functions bring in res_init.o, res_hconf.o or
mntent_r.o, which use fgets_unlocked, which is not a POSIX function.
This patch arranges for them to use __fgets_unlocked instead. (The
IS_IN (libc) conditional in rec_hconf.c is needed because that file is
also used in nscd.)
Tested for x86_64 (testsuite, and that disassembly of installed shared
libraries is unchanged by the patch except for an assertion line
number). Note that most of the linknamespace tests that failed
because of fgets_unlocked from the resolver also fail because of other
symbols brought in by the resolver, so the number of XFAILs this
removes is limited. Also note that fgets_unlocked failures for
unistd.h for XPG3/XPG4 showed up that actually unistd.h is declaring
too much for XPG3/XPG4 (bug 17665) - there is no actual need to make
getusershell.c use __fgets_unlocked (at least as regards formal
standards are concerned; maybe it should still change for
namespace-cleanness of _DEFAULT_SOURCE) because the functions there
aren't actually in any of the supported standards; the correct fix for
those failures will be to stop the *usershell* functions appearing in
unistd.h for XPG3/XPG4.
[BZ #17664]
* misc/mntent_r.c (__getmntent_r): Use __fgets_unlocked instead of
fgets_unlocked.
* resolv/res_hconf.c [IS_IN (libc)] (fgets_unlocked): Define to
__fgets_unlocked.
* resolv/res_init.c (__res_vinit): Use __fgets_unlocked instead of
fgets_unlocked.
* conform/Makefile (test-xfail-XPG4/sys/statvfs.h/linknamespace):
Remove variable.
(test-xfail-POSIX/sys/mman.h/linknamespace): Likewise.
(test-xfail-UNIX98/sys/mman.h/linknamespace): Likewise.
(test-xfail-UNIX98/sys/statvfs.h/linknamespace): Likewise.
(test-xfail-XOPEN2K/sys/mman.h/linknamespace): Likewise.
(test-xfail-XOPEN2K/sys/statvfs.h/linknamespace): Likewise.
(test-xfail-POSIX2008/sys/mman.h/linknamespace): Likewise.
(test-xfail-POSIX2008/sys/statvfs.h/linknamespace): Likewise.
(test-xfail-XOPEN2K8/sys/mman.h/linknamespace): Likewise.
(test-xfail-XOPEN2K8/sys/statvfs.h/linknamespace): Likewise.
