Introduce struct alloc_buffer to this function, and use it and
struct ns_rr_cursor in gaih_getanswer_slice. Adjust gaih_getanswer
and gaih_getanswer_noaaaa accordingly.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
If the name is not a host name, skip adding it to the result, instead
of reporting query failure. This fixes bug 12154 for getaddrinfo.
This commit still keeps the old parsing code, and only adjusts when
a host name is copied.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
Allocate the pointer arrays only at the end, when their sizes
are known. This addresses bug 29305.
Skip over invalid names instead of failing lookups. This partially
fixes bug 12154 (for gethostbyname, fixing getaddrinfo requires
different changes).
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
res_use_inet6 always returns false since commit 3f8b44be0a
("resolv: Remove support for RES_USE_INET6 and the inet6 option").
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
The simplification takes advantage of the split from getanswer_r.
It fixes various aliases issues, and optimizes NSS buffer usage.
The new DNS packet parsing helpers are used, too.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
And expand the use of name_ok and qtype in getanswer_ptr (the
former also in getanswer_r).
After further cleanups, not much code will be shared between the
two functions.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
On 32-bit machines this has no affect. On 64-bit machines
{u}int_fast{16|32} are set as {u}int64_t which is often not
ideal. Particularly x86_64 this change both saves code size and
may save instruction cost.
Full xcheck passes on x86_64.
I used these shell commands:
../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright
(cd ../glibc && git commit -am"[this commit message]")
and then ignored the output, which consisted lines saying "FOO: warning:
copyright statement not found" for each of 7061 files FOO.
I then removed trailing white space from math/tgmath.h,
support/tst-support-open-dev-null-range.c, and
sysdeps/x86_64/multiarch/strlen-vec.S, to work around the following
obscure pre-commit check failure diagnostics from Savannah. I don't
know why I run into these diagnostics whereas others evidently do not.
remote: *** 912-#endif
remote: *** 913:
remote: *** 914-
remote: *** error: lines with trailing whitespace found
...
remote: *** error: sysdeps/unix/sysv/linux/statx_cp.c: trailing lines
We stopped adding "Contributed by" or similar lines in sources in 2012
in favour of git logs and keeping the Contributors section of the
glibc manual up to date. Removing these lines makes the license
header a bit more consistent across files and also removes the
possibility of error in attribution when license blocks or files are
copied across since the contributed-by lines don't actually reflect
reality in those cases.
Move all "Contributed by" and similar lines (Written by, Test by,
etc.) into a new file CONTRIBUTED-BY to retain record of these
contributions. These contributors are also mentioned in
manual/contrib.texi, so we just maintain this additional record as a
courtesy to the earlier developers.
The following scripts were used to filter a list of files to edit in
place and to clean up the CONTRIBUTED-BY file respectively. These
were not added to the glibc sources because they're not expected to be
of any use in future given that this is a one time task:
https://gist.github.com/siddhesh/b5ecac94eabfd72ed2916d6d8157e7dchttps://gist.github.com/siddhesh/15ea1f5e435ace9774f485030695ee02
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
No abilist updates are needed because the symbols were GLIBC_PRIVATE.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
And reformat it to GNU style.
dn_skipname is used outside glibc, so do not deprecate it,
and export it as dn_skipname (not __dn_skipname). Due to internal
users, provide a __libc_dn_skipname alias, and keep __dn_skipname
as a pure compatibility symbol.
__dn_skipname@GLIBC_2.0 was moved using the script, and
dn_skipname@@GLIBC_2.34 was added using make update-all-abi.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
And reformat to GNU style.
This switches back to the dn_expand name for the ABI symbol and turns
__dn_expand into a compatibility symbol. With the improved namespace
management in current glibc, it is no longer necessary to use a
private namespace symbol. To avoid old code binding to a
GLIBC_PRIVATE symbol by accident, use __libc_dn_expand for the
internal symbol name.
The symbols dn_expand, __dnexpand were moved using
scripts/move-symbol-to-libc.py, followed by an adjustment to make
dn_expand the only GLIBC_2.34 symbol.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
I used these shell commands:
../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright
(cd ../glibc && git commit -am"[this commit message]")
and then ignored the output, which consisted lines saying "FOO: warning:
copyright statement not found" for each of 6694 files FOO.
I then removed trailing white space from benchtests/bench-pthread-locks.c
and iconvdata/tst-iconv-big5-hkscs-to-2ucs4.c, to work around this
diagnostic from Savannah:
remote: *** pre-commit check failed ...
remote: *** error: lines with trailing whitespace found
remote: error: hook declined to update refs/heads/master
The purpose of the bp[0] == '.' check is unclear. Only the root domain
starts with '.'. The empty string is accepted as a domain name in many
places, denoting the root, but using it implicitly is confusing.
Before this commit, nss_dns would send a query which did not contain a
host name as the query name (such as invalid\032name.example.com) and
then reject the answer in getanswer_r and gaih_getanswer_slice, using
a check based on res_hnok. With this commit, no query is sent, and a
host-not-found error is returned to NSS without network interaction.
This commit adds the remaining unchanging members (which are loaded
from /etc/resolv.conf) to struct resolv_conf.
The extended name server list is currently not used by the stub
resolver. The switch depends on a cleanup: The _u._ext.nssocks
array stores just a single socket, and needs to be replaced with
a single socket value.
(The compatibility gethostname implementation does not use the
extended addres sort list, either. Updating the compat code is
not worthwhile.)
struct resolv_context objects provide a temporary resolver context
which does not change during a name lookup operation. Only when the
outmost context is created, the stub resolver configuration is
verified to be current (at present, only against previous res_init
calls). Subsequent attempts to obtain the context will reuse the
result of the initial verification operation.
struct resolv_context can also be extended in the future to store
data which needs to be deallocated during thread cancellation.
In ns_name_ntop, the NS_CMPRSFLGS check is no longer needed because
labellen (called earlier) already rejects everything which is not
a plain label (compression references and extended label types).
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.
* 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
