Glibc 2.20 Version Upgrade

[Martin Ward]

Seems like configparms has been dropped. So to set the correct loader path, one must use libc_cv_rtlddir and libc_cv_slibdir respectively if needed in section 10.7 when building the c library.

For pure 64 I set both to /lib in config.cache and loaded them from there, when running configure.

[William Harrington]

​http://ftp.gnu.org/gnu/glibc/glibc-2.20.tar.xz

We can use config.cache or add to the end of the configure line as an example (slibdir isn't recognized in configparms anymore):

libc_cv_rtlddir=/lib libc_cv_slibdir=/lib

Announce message at ​https://sourceware.org/ml/libc-alpha/2014-09/msg00088.html

GNU C Library NEWS -- history of user-visible changes. Copyright (C) 1992-2014 Free Software Foundation, Inc. See the end for copying conditions.

Please send GNU C library bug reports via <​http://sourceware.org/bugzilla/> using `glibc' in the "product" field.

Version 2.20

• The following bugs are resolved with this release:

6804, 9894, 12994, 13347, 13651, 14308, 14770, 15119, 15132, 15347, 15514, 15698, 15804, 15894, 15946, 16002, 16064, 16095, 16194, 16198, 16275, 16284, 16287, 16315, 16348, 16349, 16354, 16357, 16362, 16447, 16516, 16532, 16539, 16545, 16561, 16562, 16564, 16574, 16599, 16600, 16609, 16610, 16611, 16613, 16619, 16623, 16629, 16632, 16634, 16639, 16642, 16648, 16649, 16670, 16674, 16677, 16680, 16681, 16683, 16689, 16695, 16701, 16706, 16707, 16712, 16713, 16714, 16724, 16731, 16739, 16740, 16743, 16754, 16758, 16759, 16760, 16770, 16786, 16789, 16791, 16796, 16799, 16800, 16815, 16823, 16824, 16831, 16838, 16839, 16849, 16854, 16876, 16877, 16878, 16882, 16885, 16888, 16890, 16892, 16912, 16915, 16916, 16917, 16918, 16922, 16927, 16928, 16932, 16943, 16958, 16965, 16966, 16967, 16977, 16978, 16984, 16990, 16996, 17009, 17022, 17031, 17042, 17048, 17050, 17058, 17061, 17062, 17069, 17075, 17078, 17079, 17084, 17086, 17088, 17092, 17097, 17125, 17135, 17137, 17150, 17153, 17187, 17213, 17259, 17261, 17262, 17263, 17319, 17325, 17354.

• Reverted change of ABI data structures for s390 and s390x: On s390 and s390x the size of struct ucontext and jmp_buf was increased in 2.19. This change is reverted in 2.20. The introduced 2.19 symbol versions of getcontext, setjmp, _setjmp, sigsetjmp, longjmp, _longjmp, siglongjmp are preserved pointing straight to the same implementation as the old ones. Given that, new callers will simply provide a too-big buffer to these functions. Any applications/libraries out there that embed jmp_buf or ucontext_t in an ABI-relevant data structure that have already been rebuilt against 2.19 headers will have to rebuilt again. This is necessary in any case to revert the breakage in their ABI caused by the glibc change.

• Support for file description locks is added to systems running the Linux kernel. The standard file locking interfaces are extended to operate on file descriptions, not file descriptors, via the use of F_OFD_GETLK, F_OFD_SETLK, and F_OFD_SETLKW. File description locks are associated with an open file instead of a process.

• Optimized strchr implementation for AArch64. Contributed by ARM Ltd.

• The minimum Linux kernel version that this version of the GNU C Library can be used with is 2.6.32.

• Running the testsuite no longer terminates as soon as a test fails. Instead, a file tests.sum (xtests.sum from "make xcheck") is generated, with PASS or FAIL lines for individual tests. A summary of the results is printed, including a list of failing lists, and "make check" exits with error status if there were any unexpected failures. "make check stop-on-test-failure=y" may be used to keep the old behavior.

• The am33 port, which had not worked for several years, has been removed from ports.

• The _BSD_SOURCE and _SVID_SOURCE feature test macros are no longer supported; they now act the same as _DEFAULT_SOURCE (but generate a warning). Except for cases where _BSD_SOURCE enabled BSD interfaces that conflicted with POSIX (support for which was removed in 2.19), the interfaces those macros enabled remain available when compiling with _GNU_SOURCE defined, with _DEFAULT_SOURCE defined, or without any feature test macros defined.

• Optimized strcmp implementation for ARMv7. Contributed by ARM Ltd.

• Added support for TX lock elision of pthread mutexes on s390 and s390x. This may improve lock scaling of existing programs on TX capable systems. The lock elision code is only built with --enable-lock-elision=yes and then requires a GCC version supporting the TX builtins. With lock elision default mutexes are elided via builtin_tbegin, if the cpu supports transactions. By default lock elision is not enabled and the elision code is not built.

• CVE-2014-4043 The posix_spawn_file_actions_addopen implementation did not copy the path argument. This allowed programs to cause posix_spawn to deference a dangling pointer, or use an unexpected pathname argument if the string was modified after the posix_spawn_file_actions_addopen invocation.

• All supported architectures now use the main glibc sysdeps directory instead of some being in a separate "ports" directory (which was distributed separately before glibc 2.17).

• The NPTL implementation of POSIX pthreads is no longer an "add-on". On configurations that support it (all Linux configurations), it's now used regardless of the --enable-add-ons switch to configure. It is no longer possible to build such configurations without pthreads support.

• Locale names, including those obtained from environment variables (LANG and the LC_* variables), are more tightly checked for proper syntax. setlocale will now fail (with EINVAL) for locale names that are overly long, contain slashes without starting with a slash, or contain ".." path components. (CVE-2014-0475) Previously, some valid locale names were silently replaced with the "C" locale when running in AT_SECURE mode (e.g., in a SUID program). This is no longer necessary because of the additional checks.

• On x86-64, the dynamic linker's lazy-binding support is now compatible with application code using Intel MPX instructions. (With all previous versions, the MPX register state could be clobbered when making calls into or out of a shared library.) Note that while the new dynamic linker is compatible with all known x86 hardware whether or not it supports Intel MPX, some x86 instruction-set emulators might fail to handle the new instruction encodings. This is known to affect Valgrind versions up through 3.9 (but will be fixed in the forthcoming 3.10 release), and might affect other tools that do instruction emulation.

• Support for loadable gconv transliteration modules has been removed. The support for transliteration modules has been non-functional for over a decade, and the removal is prompted by security defects. The normal gconv conversion modules are still supported. Transliteration with TRANSLIT is still possible, and the IGNORE specifier continues to be supported. (CVE-2014-5119)

• Decoding a crafted input sequence in the character sets IBM933, IBM935, IBM937, IBM939, IBM1364 could result in an out-of-bounds array read, resulting a denial-of-service security vulnerability in applications which use functions related to iconv. (CVE-2014-6040)

[William Harrington]

Fixed at commits:

a15706aadfa6e2909764f64ea5f639b9e87aa325
32c3fbd1fbbe38b19b53381272d32311b3600584