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The GNU C Library
=================

The GNU C Library version 2.24 is now available.

The GNU C Library is used as *the* C library in the GNU system and
in GNU/Linux systems, as well as many other systems that use Linux
as the kernel.

The GNU C Library is primarily designed to be a portable
and high performance C library.  It follows all relevant
standards including ISO C11 and POSIX.1-2008.  It is also
internationalized and has one of the most complete
internationalization interfaces known.

The GNU C Library webpage is at http://www.gnu.org/software/libc/

Packages for the 2.24 release may be downloaded from:
        http://ftpmirror.gnu.org/libc/
        http://ftp.gnu.org/gnu/libc/

The mirror list is at http://www.gnu.org/order/ftp.html

NEWS for version 2.24
=====================

* The minimum Linux kernel version that this version of the GNU C Library
  can be used with is 3.2, except on i[4567]86 and x86_64, where Linux
  kernel version 2.6.32 or later suffices (on architectures that already
  required kernel versions more recent than 3.2, those requirements remain
  unchanged).  Linux 3.2 or later kernel headers are required on all
  architectures.

* The pap_AN locale has been deleted.  This has been deprecated for a long
  time.  It has been replaced by pap_AW & pap_CW, both of which have long
  been included in previous releases.

* The readdir_r and readdir64_r functions have been deprecated.  It is
  recommended to use readdir and readdir64 instead.

* The type “union wait” has been removed.  It was deprecated in the early
  1990s and never part of POSIX.  Application code should use the int type
  instead of “union wait”.

* A new NSS action is added to facilitate large distributed system
  administration.  The action, MERGE, allows remote user stores like LDAP
  to be merged into local user stores like /etc/groups in order to provide
  easy to use, updated, and managed sets of merged credentials.  The new
  action can be used by configuring it in /etc/nsswitch.conf:
  group: files [SUCCESS=merge] nis
  Implemented by Stephen Gallagher (Red Hat).

* The deprecated __malloc_initialize_hook variable has been removed from the
  API.

* The long unused localedef --old-style option has been removed.  It hasn't
  done anything in over 16 years.  Scripts using this option can safely
  drop it.

* nextupl, nextup, nextupf, nextdownl, nextdown and nextdownf are added to
  libm.  They are defined by TS 18661 and IEEE754-2008.  The nextup functions
  return the next representable value in the direction of positive infinity
  and the nextdown functions return the next representable value in the
  direction of negative infinity.  These are currently enabled as GNU
  extensions.

Security related changes:

* An unnecessary stack copy in _nss_dns_getnetbyname_r was removed.  It
  could result in a stack overflow when getnetbyname was called with an
  overly long name.  (CVE-2016-3075)

* Previously, getaddrinfo copied large amounts of address data to the stack,
  even after the fix for CVE-2013-4458 has been applied, potentially
  resulting in a stack overflow.  getaddrinfo now uses a heap allocation
  instead.  Reported by Michael Petlan.  (CVE-2016-3706)

* The glob function suffered from a stack-based buffer overflow when it was
  called with the GLOB_ALTDIRFUNC flag and encountered a long file name.
  Reported by Alexander Cherepanov.  (CVE-2016-1234)

* The Sun RPC UDP client could exhaust all available stack space when
  flooded with crafted ICMP and UDP messages.  Reported by Aldy Hernandez'
  alloca plugin for GCC.  (CVE-2016-4429)

* The IPv6 name server management code in libresolv could result in a memory
  leak for each thread which is created, performs a failing naming lookup,
  and exits.  Over time, this could result in a denial of service due to
  memory exhaustion.  Reported by Matthias Schiffer.  (CVE-2016-5417)

The following bugs are resolved with this release:

  [1170] localedata: ne_NP: update Nepali locale definition file
  [3629] manual: stpcpy description in string.texi refers to MS-DOG instead
    of MS-DOS.
  [6527] malloc: [powerpc] Malloc alignment insufficient for PowerPC
  [6796] math: fdim() does not set errno on overflow
  [10354] libc: posix_spawn should use vfork() in more cases than presently
  [11213] localedata: localedata: add copyright disclaimer to locale files
  [12143] localedata: chr_US: new Cherokee locale
  [12450] localedata: sgs_LT: new locale
  [12676] localedata: ln_CD: new locale
  [13237] localedata: LC_ADDRESS.country_name: update all locales w/latest
    CLDR data
  [13304] math: fma, fmaf, fmal produce wrong results
  [14259] build: --localedir arg to configure is ignored
  [14499] nptl: Does posix_spawn invoke atfork handlers / use vfork?
  [14750] libc: Race condition in posix_spawn vfork usage vs signal handlers
  [14934] localedata: es_CL: wrong first weekday chilean locale
  [15262] localedata: LC_MESSAGES.yesexpr/noexpr: inconsistent use of
    romanisation
  [15263] localedata: LC_MESSAGES.yesexpr/noexpr: inconsistent use of 1/0
    and +/-
  [15264] localedata: LC_MESSAGES.yesstr/nostr: lacking in many locales
  [15368] nptl: raise() is not async-signal-safe
  [15479] math: ceil, floor, round and trunc raise inexact exception
  [15578] localedata: kk_KZ: various updates
  [16003] localedata: pap_AN: punt old locale
  [16137] localedata: iw_IL: punt old locale
  [16190] localedata: eo: new esperanto locale
  [16374] localedata: lv_LV: change currency symbol in LC_MONETARY to euro
  [16742] malloc: race condition: pthread_atfork() called before first
    malloc() results in unexpected locking behaviour/deadlocks
  [16975] localedata: LC_MESSAGES.yesexpr/noexpr: revisit capitalization in
    all locales
  [16983] localedata: postal_fmt does not allow %l and %n modifiers
  [17565] localedata: pt_PT: wrong (work-)week start
  [17899] math: [powerpc] floorl returns negative zero with FE_DOWNWARD
  [17950] build: Build fails with -msse
  [18205] localedata: be_BY*: wrong first_weekday and first_workday
  [18433] libc: posix_spawn does not return correctly upon failure to
    execute
  [18453] localedata: charmaps/IBM875: incorrect codes
  [18712] string: bits/string2.h incompatible with -O2 -Werror=packed
    -Wsystem-headers
  [18896] localedata: he_IL: improvements for currency
  [18911] localedata: ro_RO: Correcting week day name for "Tuesday" in
    Romanian locale data
  [18960] locale: s390: _nl_locale_subfreeres uses larl opcode on misaligned
    symbol
  [19056] libc: Deprecate readdir_r
  [19133] localedata: pt_*: days & months should be lowercase in Portuguese
    language
  [19198] localedata: nl_NL: small improvements for Dutch locales
  [19257] network: Per-thread memory leak in __res_vinit with IPv6
    nameservers (CVE-2016-5417)
  [19269] build: tst-audit4 and tst-audit10 failures with gcc-6 on non avx
    machine
  [19400] locale: Language missing in  "iso-639.def", trivial fix in
    description
  [19431] malloc: Deadlock between fflush, getdelim, and fork
  [19505] libc: Incorrect file descriptor validity checks in
    posix_spawn_file_actions_add{open,close,dup2}
  [19509] dynamic-link: dlsym, dlvsym do not report errors through dlerror
    when using RTLD_NEXT
  [19512] locale: Stale `#ifndef HAVE_BUILTIN_EXPECT' in
    `intl/{gettextP,loadinfo}.h'
  [19534] libc: execle, execlp may use malloc
  [19568] localedata: *_CH: Swiss locales have inconsistent start of week
  [19573] network: res_nclose and __res_maybe_init disagree about name
    server initialization, breaking Hesiod
  [19575] localedata: Status of GB18030 tables
  [19581] localedata: sr_* date_fmt string contains additional newline
  [19583] string: SSSE3_Fast_Copy_Backward flag needs to be enabled for AMD
    Excavator core
  [19592] math: [ldbl-128ibm] ceill incorrect in non-default rounding modes
  [19593] math: [ldbl-128ibm] truncl incorrect in non-default rounding modes
  [19594] math: [ldbl-128ibm] roundl incorrect in non-default rounding modes
  [19595] math: [ldbl-128ibm] fmodl incorrect for results in subnormal
    double range
  [19602] math: [ldbl-128ibm] fmodl handling of equal arguments with low
    part zero incorrect
  [19603] math: [ldbl-128ibm] remainderl, remquol incorrect sign handling in
    equality tests
  [19610] dynamic-link: ldconfig -X removes stale symbolic links
  [19613] libc: s390x (64 bit) macro expansion WCOREDUMP and others
  [19633] locale: strfmon_l applies global locale to number formatting
  [19642] network: Memory leak in getnameinfo
  [19648] libc: test-skeleton.c: Do not set RLIMIT_DATA
  [19653] libc: Potential for NULL pointer dereference (CWE-476) in
    glibc-2.22
  [19654] math: [x86_64] Need testcase for BZ #19590 fix
  [19671] localedata: Missing Sanity Check for malloc() in 'tst-fmon.c' &
    'tst-numeric.c'
  [19674] math: [ldbl-128ibm] powl incorrect overflow handling
  [19677] math: [ldbl-128ibm] remainderl equality test incorrect for zero
    low part
  [19678] math: [ldbl-128ibm] nextafterl, nexttowardl incorrect sign of zero
    result
  [19679] dynamic-link: gcc-4.9.3 C++ exception handling broken due to
    unaligned stack
  [19726] locale: Converting UCS4LE to INTERNAL with iconv() does not update
    pointers and lengths in error-case.
  [19727] locale: Converting from/to UTF-xx with iconv() does not always
    report errors on UTF-16 surrogates values.
  [19755] nscd: nscd assertion failure in gc
  [19758] dynamic-link: Typo in EXTRA_LD_ENVVARS for x86-64
  [19759] libc: mempcpy shouldn't be inlined
  [19762] dynamic-link: HAS_CPU_FEATURE/HAS_ARCH_FEATURE are easy to misuse
  [19765] libc: s390 needs an optimized mempcpy
  [19779] glob: glob: buffer overflow with GLOB_ALTDIRFUNC due to incorrect
    NAME_MAX limit assumption (CVE-2016-1234)
  [19783] build: benchtests don't support --enable-hardcoded-path-in-tests
  [19787] network: Missing and incorrect truncation checks in getnameinfo
  [19790] math: [ldbl-128ibm] nearbyintl incorrect in non-default rounding
    modes
  [19791] network: Assertion failure in res_query.c with un-connectable name
    server addresses
  [19792] libc: MIPS: backtrace yields infinite backtrace with makecontext
  [19822] math: libm.so install clobbers old version
  [19825] network: resolv: send_vc can return uninitialized data in second
    response to getaddrinfo
  [19830] network: nss_dns: should check RDATA length against buffer length
  [19831] network: nss_dns: getaddrinfo returns uninitialized data when
    confronted with A/AAAA records of invalid size
  [19837] nss: nss_db: No retries for some long lines with a larger buffer
  [19848] math: powl(10,n) for n=-4,-5,-6,-7 is off by more than 1 ULP
  [19853] stdio: Printing IBM long double in decimal with high precision is
    sometimes incorrect
  [19860] build: x86_64: compile errors for tst-audit10 and tst-auditmod10b
  [19861] nptl: libpthread IFUNC resolver for fork can lead to crash
  [19862] network: resolv, nss_dns: Remove remaining logging of unexpected
    record types
  [19865] network: Assertion failure or memory leak in
    _nss_dns_getcanonname_r
  [19868] network: nss_dns: netent code does not skip over non-PTR records
  [19879] network: nss_dns: Stack overflow in getnetbyname implementation
    (CVE-2016-3075)
  [19881] string: Improve x86-64 memset
  [19907] string: Incorrect memcpy tests
  [19916] dynamic-link: S390: fprs/vrs are not saved/restored while
    resolving symbols
  [19925] libc: termios.h XCASE namespace
  [19928] string: memmove-vec-unaligned-erms.S is slow with large data size
  [19929] libc: limits.h NL_NMAX namespace
  [19931] stdio: Memory leak in vfprintf
  [19957] libc: clone(CLONE_VM) access invalid parent memory
  [19963] localedata: en_IL: New locale
  [19989] stdio: stdio.h cuserid namespace
  [19994] network: getaddrinfo does not restore RES_USE_INET6 flag in
    gethosts
  [19996] locale: langinfo.h nl_langinfo_l namespace
  [20005] stdio: fflush on a file opened with fmemopen resets position to 0
  [20010] network: getaddrinfo: Stack overflow in hostent translation
    (CVE-2016-3706)
  [20012] stdio: libio: fmemopen append mode failure
  [20014] stdio: stdio.h namespace for pre-threads POSIX
  [20017] network: resolv: Use gmtime_r instead of gmtime in p_secstodate
  [20023] libc: fcntl.h timespec namespace
  [20024] math: [x86_64] vectorized sincos trashes the stack
  [20031] network: nss_hesiod: Heap overflow in get_txt_records
  [20041] time: sys/time.h timespec namespace
  [20043] libc: unistd.h missing cuserid for UNIX98 and before
  [20044] libc: unistd.h missing pthread_atfork for UNIX98
  [20051] libc: ttyslot in wrong header under wrong conditions
  [20054] libc: gethostname not declared for XPG4
  [20055] libc: termios.h missing tcgetsid for XPG4
  [20072] dynamic-link: x86 init_cpu_features is called twice in static
    executable
  [20073] libc: sys/stat.h fchmod namespace
  [20074] libc: stdlib.h rand_r namespace
  [20076] libc: sys/stat.h missing S_IFSOCK, S_ISSOCK for XPG4
  [20094] libc: stdlib.h should not declare grantpt, ptsname, unlockpt for
    XPG3
  [20111] libc: struct sockaddr_storage cannot be aggregate-copied
  [20112] network: sunrpc: stack (frame) overflow in Sun RPC clntudp_call
    (CVE-2016-4429)
  [20115] string: Extra alignment in memset-vec-unaligned-erms.S
  [20119] libc: Wrong mask for processors level type from CPUID
  [20139] dynamic-link: Upper part of zmm is zeroed if Glibc is built with
    AS not supporting AVX512
  [20151] math: [ldbl-128/ldbl-128ibm] j0l, j1l, y0l, y1l return sNaN for
    sNaN argument
  [20153] math: [ldbl-128ibm] sqrtl (sNaN) returns sNaN
  [20156] math: [ldbl-128ibm] ceill, rintl etc. return sNaN for sNaN
    argument
  [20157] math: [powerpc] fabsl (sNaN) wrongly raises "invalid"
  [20160] math: [powerpc] ceil, rint etc. return sNaN for sNaN input
  [20178] libc: posix_spawn{p} should not call exit
  [20191] stdio: libio: vtables hardening
  [20195] string: FMA4 detection requires CPUID execution with register
    eax=0x80000001
  [20198] libc: quick_exit incorrectly destroys C++11 thread objects.
  [20205] math: [i386/x86_64] nextafterl incorrect incrementing negative
    subnormals
  [20212] math: acos (sNaN) returns sNaN
  [20213] math: asin (sNaN) returns sNaN
  [20214] network: Linux header sync with linux/in6.h and ipv6.h again.
  [20218] math: [i386] asinhl (sNaN) returns sNaN
  [20219] math: [i386] atanhl (sNaN) returns sNaN
  [20222] stdio: fopencookie: Mangle function pointers
  [20224] math: [i386] cbrtl (sNaN) returns sNaN
  [20225] math: ldexp, scalbn, scalbln return sNaN for sNaN input
  [20226] math: [i386/x86_64] expl, exp10l, expm1l return sNaN for sNaN
    input
  [20227] math: [i386/x86_64] logl (sNaN) returns sNaN
  [20228] math: [i386/x86_64] log10l (sNaN) returns sNaN
  [20229] math: [i386/x86_64] log1pl (sNaN) returns sNaN
  [20232] math: [ldbl-128] expm1l (sNaN) returns sNaN
  [20233] math: [ldbl-128ibm] expm1l (sNaN) returns sNaN
  [20234] math: [ldbl-128ibm] log1pl (sNaN) returns sNaN
  [20235] math: [i386/x86_64] log2l (sNaN) returns sNaN
  [20237] nss: nss_db: get*ent segfaults without preceding set*ent
  [20240] math: modf (sNaN) returns sNaN
  [20248] libc: debug/tst-longjump_chk2 calls printf from a signal handler
  [20250] math: frexp (sNaN) returns sNaN
  [20252] math: atan2 (sNaN, qNaN) fails to raise "invalid"
  [20255] math: [i386] fdim, fdimf return with excess range and precision /
    double rounding
  [20256] math: [i386/x86_64] fdiml returns sNaN for sNaN input
  [20260] string: ../sysdeps/x86/bits/string.h:1092:3: error: array
    subscript is below array bounds [-Werror=array-bounds]
  [20262] nis: _nss_nis_initgroups_dyn always returns NSS_STATUS_NOTFOUND
  [20263] nptl: robust mutex deadlocks if other thread requests timedlock
    (Only arm/linux)
  [20277] libc: $dp is not initialized correctly in sysdeps/hppa/start.S
  [20284] malloc: malloc: Corrupt arena avoidance causes unnecessary mmap
    fallbacks
  [20296] math: [i386/x86_64] scalbl returns sNaN for sNaN input, missing
    "invalid" exceptions
  [20314] nptl: make[4]: *** [/usr/include/stdlib.h] Error 1
  [20316] localedata: id_ID: Februari instead of Pebruari
  [20327] string: POWER8 strcasecmp returns incorrect result
  [20347] math: Failure: Test: j0_downward (0xap+0)
  [20348] libc: FAIL: misc/tst-preadvwritev64
  [20349] libc: 64-bit value is passed differently in p{readv,writev}{64}
  [20350] libc: There is no test for p{read,write}64
  [20357] math: Incorrect cos result for 1.5174239687223976
  [20384] build: Don't run libmvec-sincos-avx* tests on non avx machines

Contributors
============

This release was made possible by the contributions of many people.
The maintainers are grateful to everyone who has contributed
changes or bug reports.  These include:

Adhemerval Zanella
Andreas Schwab
Andrew Senkevich
Anton Blanchard
Arnas Udovičius
Aurelien Jarno
Carlos Eduardo Seo
Carlos O'Donell
Chris Metcalf
Chung-Lin Tang
Claude Paroz
Dimitris Pappas
Dmitry V. Levin
Dylan Alex Simon
Eduardo Trápani
Florian Weimer
Gabriel F. T. Gomes
Gunnar Hjalmarsson
Gustavo Romero
Guy Rutenberg
H.J. Lu
Hongjiu Zhang
Jiyoung Yun
John David Anglin
Joseph Myers
Khem Raj
Maciej W. Rozycki
Mark Wielaard
Marko Myllynen
Martin Galvan
Matthew Fortune
Matthias Wallnoefer
Mike FABIAN
Mike Frysinger
Neskie Manuel
Nick Alcock
Paras pradhan
Paul E. Murphy
Paul Pluzhnikov
Rajalakshmi Srinivasaraghavan
Rical Jasan
Richard Henderson
Robin van der Vliet
Roland McGrath
Samuel Thibault
Siddhesh Poyarekar
Simion Onea
Stefan Liebler
Stephen Gallagher
Szabolcs Nagy
Timur Birsh
Torvald Riegel
Tulio Magno Quites Machado Filho
Wilco Dijkstra
Will Newton
Yvan Roux
Zack Weinberg