Commit graph

153 commits

Author SHA1 Message Date
Nick Alcock de6591238b Do not stack-protect ifunc resolvers [BZ #7065]
When dynamically linking, ifunc resolvers are called before TLS is
initialized, so they cannot be safely stack-protected.

We avoid disabling stack-protection on large numbers of files by
using __attribute__ ((__optimize__ ("-fno-stack-protector")))
to turn it off just for the resolvers themselves.  (We provide
the attribute even when statically linking, because we will later
use it elsewhere too.)
2016-12-26 10:08:41 +01:00
Nick Alcock 03baef1c9c Configure support for --enable-stack-protector [BZ #7065]
This adds =all and =strong, with obvious semantics, defaulting to off.

We don't validate the value of the option yet: that's in a later patch.
Nor do we use it for anything at this stage.

We differentiate between 'the compiler understands -fstack-protector'
and 'the user wanted -fstack-protector' so that we can pass
-fno-stack-protector in appropriate places even if the user didn't want
to turn on -fstack-protector for other parts.  (This helps us overcome
another existing limitation, that glibc doesn't work with GCCs hacked
to pass in -fstack-protector by default.)

We also arrange to set the STACK_PROTECTOR_LEVEL #define to a value
appropriate for the stack-protection level in use for each file in
particular.
2016-12-26 10:08:19 +01:00
Stefan Liebler 022dfdce00 Add configure check to test if gcc supports attribute ifunc.
This patch adds a configure check to test if gcc supports attribute ifunc.
The support can either be enabled in <gcc-src>/gcc/config.gcc for one
architecture in general by setting default_gnu_indirect_function variable to yes
or by configuring gcc with --enable-gnu-indirect-function.

The next patch rewrites libc_ifunc macro to use gcc attribute ifunc instead
of inline assembly to generate the IFUNC symbols due to false debuginfo.

If gcc does not support attribute ifunc, the old approach for generating
ifunc'ed symbols is used. Then the debug-information is false. Thus it is
recommended to use a gcc with indirect function support (See notes in INSTALL).
After this patch-series these inline assemblies for ifunc-handling are not
scattered in multiple files but are used only indirect via ifunc-macros
and can simply removed in libc-symbols.h in future.

If glibc is configured with --enable-multi-arch and gcc does not support
attribute ifunc, a configure warning is dumped!

ChangeLog:

	* config.h.in (HAVE_GCC_IFUNC): New undef.
	* configure.ac: Add check if gcc supports attribute ifunc feature.
	* configure: Regenerated.
	* manual/install.texi: Add recommendation for gcc with
	indirect-function support.
	* INSTALL: Regenerated.
2016-10-07 10:02:59 +02:00
Stefan Liebler e9b424881a S390: Do not set FE_INEXACT with feraiseexcept (FE_OWERFLOW|FE_UNDERFLOW).
On s390 feraiseexcept (FE_OVERFLOW|FE_UNDERFLOW) sets FE_INEXACT, too.
This patch uses z196 zarch load rounded instruction which can suppress
FE_INEXACT exception if gcc has z196 support in used configuration.
Otherwise FE_INEXACT flag is set as before. The gcc support is tested
in a new configure-check.

A comment in fsetexcptflg.c is corrected as new exceptions are not
executed with the next floating-point instruction if fpc is set with
_FPU_SETCW macro. It seems the comment was copied e.g. from
sysdeps/x86_64/fpu/fsetexcptflg.c file.

ChangeLog:

	* config.h.in (HAVE_S390_MIN_Z196_ZARCH_ASM_SUPPORT):
	New undefine.
	* sysdeps/s390/configure.ac: Add test for z196 zarch support.
	* sysdeps/s390/configure: Regenerated.
	* sysdeps/s390/fpu/fraiseexcpt.c (__feraiseexcept): Use ledbra
	instruction for raising over-/underflow if z196 zarch is supported
	by default.
	* sysdeps/s390/fpu/fsetexcptflg.c (fesetexceptflag):
	Correct comment.
2016-08-31 14:54:55 +02:00
H.J. Lu f43cb35c9b Require binutils 2.24 to build x86-64 glibc [BZ #20139]
If assembler doesn't support AVX512DQ, _dl_runtime_resolve_avx is used
to save the first 8 vector registers, which only saves the lower 256
bits of vector register, for lazy binding.  When it is called on AVX512
platform, the upper 256 bits of ZMM registers are clobbered.  Parameters
passed in ZMM registers will be wrong when the function is called the
first time.  This patch requires binutils 2.24, whose assembler can store
and load ZMM registers, to build x86-64 glibc.  Since mathvec library
needs assembler support for AVX512DQ,  we disable mathvec if assembler
doesn't support AVX512DQ.

	[BZ #20139]
	* config.h.in (HAVE_AVX512_ASM_SUPPORT): Renamed to ...
	(HAVE_AVX512DQ_ASM_SUPPORT): This.
	* sysdeps/x86_64/configure.ac: Require assembler from binutils
	2.24 or above.
	(HAVE_AVX512_ASM_SUPPORT): Removed.
	(HAVE_AVX512DQ_ASM_SUPPORT): New.
	* sysdeps/x86_64/configure: Regenerated.
	* sysdeps/x86_64/dl-trampoline.S: Make HAVE_AVX512_ASM_SUPPORT
	check unconditional.
	* sysdeps/x86_64/multiarch/ifunc-impl-list.c: Likewise.
	* sysdeps/x86_64/multiarch/memcpy.S: Likewise.
	* sysdeps/x86_64/multiarch/memcpy_chk.S: Likewise.
	* sysdeps/x86_64/multiarch/memmove-avx512-no-vzeroupper.S:
	Likewise.
	* sysdeps/x86_64/multiarch/memmove-avx512-unaligned-erms.S:
	Likewise.
	* sysdeps/x86_64/multiarch/memmove.S: Likewise.
	* sysdeps/x86_64/multiarch/memmove_chk.S: Likewise.
	* sysdeps/x86_64/multiarch/mempcpy.S: Likewise.
	* sysdeps/x86_64/multiarch/mempcpy_chk.S: Likewise.
	* sysdeps/x86_64/multiarch/memset-avx512-no-vzeroupper.S:
	Likewise.
	* sysdeps/x86_64/multiarch/memset-avx512-unaligned-erms.S:
	Likewise.
	* sysdeps/x86_64/multiarch/memset.S: Likewise.
	* sysdeps/x86_64/multiarch/memset_chk.S: Likewise.
	* sysdeps/x86_64/fpu/multiarch/svml_d_cos8_core_avx512.S: Check
	HAVE_AVX512DQ_ASM_SUPPORT instead of HAVE_AVX512_ASM_SUPPORT.
	* sysdeps/x86_64/fpu/multiarch/svml_d_exp8_core_avx512.S:
	Likewise.
	* sysdeps/x86_64/fpu/multiarch/svml_d_log8_core_avx512.S:
	Likewise.
	* sysdeps/x86_64/fpu/multiarch/svml_d_pow8_core_avx512.S:
	Likewise.
	* sysdeps/x86_64/fpu/multiarch/svml_d_sin8_core_avx512.S:
	Likewise.
	* sysdeps/x86_64/fpu/multiarch/svml_d_sincos8_core_avx512.:
	Likewise.
	* sysdeps/x86_64/fpu/multiarch/svml_s_cosf16_core_avx512.S:
	Likewise.
	* sysdeps/x86_64/fpu/multiarch/svml_s_expf16_core_avx512.S:
	Likewise.
	* sysdeps/x86_64/fpu/multiarch/svml_s_logf16_core_avx512.S:
	Likewise.
	* sysdeps/x86_64/fpu/multiarch/svml_s_powf16_core_avx512.S:
	Likewise.
	* sysdeps/x86_64/fpu/multiarch/svml_s_sincosf16_core_avx51:
	Likewise.
	* sysdeps/x86_64/fpu/multiarch/svml_s_sinf16_core_avx512.S:
	Likewise.
2016-07-01 06:03:05 -07:00
Stefan Liebler 9b7f05599a S390: Configure check for vector support in gcc.
The S390 specific test checks if the gcc has support for vector registers
by compiling an inline assembly which clobbers vector registers.
On success the macro HAVE_S390_VX_GCC_SUPPORT is defined.
This macro can be used to determine if e.g. clobbering vector registers
is allowed or not.

ChangeLog:

	* config.h.in (HAVE_S390_VX_GCC_SUPPORT): New macro undefine.
	* sysdeps/s390/configure.ac: Add test for S390 vector register
	support in gcc.
	* sysdeps/s390/configure: Regenerated.
2016-05-25 17:18:04 +02:00
H.J. Lu 6901def689 Avoid an extra branch to PLT for -z now
When --enable-bind-now is used to configure glibc build, we can avoid
an extra branch to the PLT entry by using indirect branch via the GOT
slot instead, which is similar to the first instructuon in the PLT
entry.  Changes in the shared library sizes in text sections:

Shared library    Before (bytes)   After (bytes)
libm.so             1060813          1060797
libmvec.so           160881           160805
libpthread.so         94992            94984
librt.so              25064            25048

	* config.h.in (BIND_NOW): New.
	* configure.ac (BIND_NOW): New.  Defined for --enable-bind-now.
	* configure: Regenerated.
	* sysdeps/x86_64/sysdep.h (JUMPTARGET)[BIND_NOW]: Defined to
	indirect branch via the GOT slot.
2016-05-24 08:44:23 -07:00
Joseph Myers f4a2740a69 Remove linux/fanotify.h configure test.
Now we require Linux 3.2 or later kernel headers everywhere, the
configure test for <linux/fanotify.h> is obsolete; this patch removes
it.

Tested for x86_64.

	* sysdeps/unix/sysv/linux/configure.ac (linux/fanotify.h): Do not
	test for header.
	* sysdeps/unix/sysv/linux/configure: Regenerated.
	* config.h.in (HAVE_LINUX_FANOTIFY_H): Remove #undef.
	* sysdeps/unix/sysv/linux/tst-fanotify.c [!HAVE_LINUX_FANOTIFY_H]:
	Remove conditional code.
	[HAVE_LINUX_FANOTIFY_H]: Make code unconditional.
2016-02-24 18:44:10 +00:00
Dmitry V. Levin 80fcb5c583 intl: reintroduce unintentionally disabled optimization
HAVE_BUILTIN_EXPECT macro was removed by commit glibc-2.14-280-g3ce1f29,
but then its use was unintentionally reintroduced during merge with GNU
gettext 0.19.3 by commit glibc-2.20-324-g6d24885, effectively disabling
all optimization based on __builtin_expect.  As intl files are also part
of GNU gettext, HAVE_BUILTIN_EXPECT macro cannot be removed, so define
it unconditionally in config.h.in instead.

[BZ #19512]
* config.h.in (HAVE_BUILTIN_EXPECT): New macro.
2016-02-22 22:00:00 +00:00
Joseph Myers c871b9b096 Remove -mavx2 configure tests.
There are configure tests for the -mavx2 compiler option.  AVX2
support was added in GCC 4.7, so these tests are now obsolete; this
patch removes them.

Tested for x86_64 and x86 (testsuite, and that installed stripped
shared libraries are unchanged by the patch).

	* sysdeps/i386/configure.ac (libc_cv_cc_avx2): Remove configure
	test.
	* sysdeps/i386/configure: Regenerated.
	* sysdeps/x86_64/configure.ac (libc_cv_cc_avx2): Remove configure
	test.
	* sysdeps/x86_64/configure: Regenerated.
	* config.h.in (HAVE_AVX2_SUPPORT): Remove #undef.
	* sysdeps/x86_64/multiarch/Makefile (sysdep_routines): Add
	memset-avx2 unconditionally instead of conditionally on
	[$(config-cflags-avx2) = yes].
	* sysdeps/x86_64/multiarch/ifunc-impl-list.c
	(__libc_ifunc_impl_list) [HAVE_AVX2_SUPPORT]: Make code
	unconditional.
	* sysdeps/x86_64/multiarch/memset.S [HAVE_AVX2_SUPPORT]: Likewise.
	* sysdeps/x86_64/multiarch/memset_chk.S
	[IS_IN (libc) && SHARED && HAVE_AVX2_SUPPORT]: Change conditional
	to [IS_IN (libc) && SHARED].
2015-10-28 13:29:03 +00:00
Joseph Myers 3e2ee6f0e3 Remove sysdeps/nptl/configure.ac.
sysdeps/nptl/configure.ac tests for forced unwind support and the C
cleanup attribute, giving errors if either is unsupported.  It does
nothing beyond running those two tests.

Both the attribute, and _Unwind_GetCFA which is used in the forced
unwind test, were added in GCC 3.3.  Thus these tests are long
obsolete, and this patch removes the configure fragment running them,
along with associated conditionals.

Tested for x86_64 and x86 (testsuite, and that installed stripped
shared libraries are unchanged by the patch).

	* sysdeps/nptl/configure.ac: Remove file.
	* sysdeps/nptl/configure: Remove generated file.
	* configure.ac (libc_cv_forced_unwind): Do not substitute.
	* configure: Regenerated.
	* config.h.in (HAVE_FORCED_UNWIND): Remove #undef.
	* config.make.in (have-forced-unwind): Remove variable.
	* nptl/Makefile [$(have-forced-unwind) = yes]: Make code
	unconditional.
	* nptl/descr.h [HAVE_FORCED_UNWIND]: Likewise.
	* nptl/unwind.c [HAVE_FORCED_UNWIND]: Likewise.
	(__pthread_unwind) [!HAVE_FORCED_UNWIND]: Remove conditional code.
	* nptl/version.c [HAVE_FORCED_UNWIND]: Make code unconditional.
	* sysdeps/nptl/Makefile [$(have-forced-unwind) = yes]: Make code
	unconditional.
2015-10-27 21:46:03 +00:00
Joseph Myers 864198ed30 Remove gnu_unique_object configure test.
There is a configure test for assembler support for the
gnu_unique_object symbol type.  This support was added in binutils
2.20, so is present in all versions supported for building glibc.

Thus, I think the configure test can be removed; this patch does so.
Now, there is a caveat that the gas NEWS entry refers to this as a
feature for GNU/Linux targets.  But the condition is use of
ELFOSABI_GNU or ELFOSABI_NONE.  ELFOSABI_GNU covers Hurd as well as
GNU/Linux (as was the case with the older ELFOSABI_LINUX name), and
ELFOSABI_NONE means this is effectively OS-independent.  Furthermore,
I think a correct binutils port for any glibc target ought to support
this feature for use with glibc; glibc supports this as an
OS-independent feature (the configure test is only about glibc
testcases).

Tested for x86_64 (testsuite, and that installed shared libraries are
unchanged by the patch).

	* configure.ac (libc_cv_asm_unique_object): Remove configure test.
	* configure: Regenerated.
	* config.h.in (HAVE_ASM_UNIQUE_OBJECT): Remove #undef.
	* elf/tst-unique1.c (do_test) [HAVE_ASM_UNIQUE_OBJECT]: Make code
	unconditional.
	* elf/tst-unique1mod1.c [HAVE_ASM_UNIQUE_OBJECT]: Likewise.
	* elf/tst-unique1mod2.c [HAVE_ASM_UNIQUE_OBJECT]: Likewise.
	* elf/tst-unique2.c (do_test) [HAVE_ASM_UNIQUE_OBJECT]: Likewise.
	(do_test) [!HAVE_ASM_UNIQUE_OBJECT]: Remove conditional code.
	* elf/tst-unique2mod1.c [HAVE_ASM_UNIQUE_OBJECT]: Make code
	unconditional.
	* elf/tst-unique2mod2.c [HAVE_ASM_UNIQUE_OBJECT]: Likewise.
2015-10-19 22:34:20 +00:00
Joseph Myers 210dd78238 Remove .weak, .weakext configure tests.
There are configure tests for assembler .weak support, and, as a
fallback, for .weakext support.

.weakext appears to be an ECOFF thing (although a few ELF targets
support it as well).  .weak has been supported by the GNU assembler
for ELF targets since version 2.2, so given the requirement for ELF
the configure tests are obsolete; this patch removes them.

Tested for x86_64 (testsuite, and that installed shared libraries are
unchanged by the patch).

	* configure.ac (libc_cv_asm_weak_directive): Remove configure
	test.
	(libc_cv_asm_weakext_directive): Likewise.
	* configure: Regenerated.
	* config.h.in (HAVE_ASM_WEAK_DIRECTIVE): Remove #undef.
	(HAVE_ASM_WEAKEXT_DIRECTIVE): Likewise.
	* include/libc-symbols.h
	[!HAVE_ASM_WEAK_DIRECTIVE && !HAVE_ASM_WEAKEXT_DIRECTIVE]: Remove
	#error.
	[HAVE_ASM_WEAKEXT_DIRECTIVE]: Remove conditional code.
	[!HAVE_ASM_WEAKEXT_DIRECTIVE]: Make code unconditional.
2015-10-19 12:06:00 +00:00
Joseph Myers 75b0964bc8 Remove .previous, .popsection configure tests.
There is a configure test for the assembler .previous directive, and,
as a fallback, for .popsection.

glibc now only supports ELF.  For ELF, the GNU assembler has supported
.previous since version 2.2 (support added by

Mon Jul 19 15:21:20 1993  Ken Raeburn  (raeburn@rtl.cygnus.com)

        * config/obj-elf.c (obj_elf_previous): New function.
        (previous_section, previous_subsection): New vars.
        (obj_elf_section): Save current place in case DWARF code wants us
        to pop back to it.  Handle unquoted section name as well as quoted
        section name.  Don't crash on invalid strings.
        (obj_pseudo_table): Handle new pseudos "previous", "2byte", and
        "4byte".

).  Thus this configure test is obsolete, and this patch removes it
(and with it the fallback .popsection test).

Tested for x86_64 and x86 (testsuite, and that installed shared
libraries are unchanged by the patch).

	* configure.ac (libc_cv_asm_previous_directive): Remove configure
	test.
	(libc_cv_asm_popsection_directive): Likewise.
	* configure: Regenerated.
	* config.h.in (HAVE_ASM_PREVIOUS_DIRECTIVE): Remove #undef.
	(HAVE_ASM_POPSECTION_DIRECTIVE): Likewise.
	* include/libc-symbols.h [HAVE_ASM_PREVIOUS_DIRECTIVE]
	(__make_section_unallocated): Make definition unconditional.
	[HAVE_ASM_POPSECTION_DIRECTIVE] (__make_section_unallocated):
	Remove conditional definition.
	[!HAVE_ASM_PREVIOUS_DIRECTIVE && !HAVE_ASM_POPSECTION_DIRECTIVE]
	(__make_section_unallocated): Likewise.
2015-10-15 19:47:55 +00:00
Joseph Myers e8dab9477f Fix powerpc32 llrint, llrintf bad exceptions (bug 16422).
The versions of llrint and llrintf for older powerpc32 processors
convert the results of __rint / __rintf to long long int, resulting in
spurious exceptions from such casts in certain cases.  This patch
makes glibc work around the problems with the libgcc conversions when
the compiler used to build glibc doesn't use the fctidz instruction
for them.

Tested for powerpc.

	[BZ #16422]
	* sysdeps/powerpc/powerpc32/fpu/configure.ac (libc_cv_ppc_fctidz):
	New configure test.
	* sysdeps/powerpc/powerpc32/fpu/configure: Regenerated.
	* config.h.in [_LIBC] (HAVE_PPC_FCTIDZ): New macro.
	* sysdeps/powerpc/powerpc32/fpu/s_llrint.c: Include <limits.h>,
	<math_private.h> and <stdint.h>.
	(__llrint): Avoid conversions to long long int where those might
	raise spurious exceptions.
	* sysdeps/powerpc/powerpc32/fpu/s_llrintf.c: Include
	<math_private.h> and <stdint.h>.
	(__llrintf): Avoid conversions to long long int where those might
	raise spurious exceptions.
2015-10-13 00:52:54 +00:00
Joseph Myers b7848899a5 Remove configure tests for FMA4 support.
GCC added support for -mfma4 in version 4.5.  Thus the configure tests
for this support are obsolete, and this patch removes them.

Tested for x86_64 and x86 (testsuite, and that installed stripped
shared libraries are unchanged by this patch).

	* sysdeps/i386/configure.ac (libc_cv_cc_fma4): Remove configure
	test.
	* sysdeps/i386/configure: Regenerated.
	* sysdeps/x86_64/configure.ac (libc_cv_cc_fma4): Remove configure
	test.
	* sysdeps/x86_64/configure: Regenerated.
	* sysdeps/x86_64/fpu/multiarch/Makefile [$(have-mfma4) = yes]:
	Make code unconditional.
	* sysdeps/x86_64/fpu/multiarch/e_asin.c [HAVE_FMA4_SUPPORT]:
	Likewise.
	* sysdeps/x86_64/fpu/multiarch/e_atan2.c [HAVE_FMA4_SUPPORT]:
	Likewise.
	[!HAVE_FMA4_SUPPORT]: Remove conditional code.
	* sysdeps/x86_64/fpu/multiarch/e_exp.c [HAVE_FMA4_SUPPORT]: Make
	code unconditional.
	[!HAVE_FMA4_SUPPORT]: Remove conditional code.
	* sysdeps/x86_64/fpu/multiarch/e_log.c [HAVE_FMA4_SUPPORT]: Make
	code unconditional.
	[!HAVE_FMA4_SUPPORT]: Remove conditional code.
	* sysdeps/x86_64/fpu/multiarch/e_pow.c [HAVE_FMA4_SUPPORT]: Make
	code unconditional.
	* sysdeps/x86_64/fpu/multiarch/s_atan.c [HAVE_FMA4_SUPPORT]: Make
	code unconditional.
	[!HAVE_FMA4_SUPPORT]: Remove conditional code.
	* sysdeps/x86_64/fpu/multiarch/s_fma.c [HAVE_FMA4_SUPPORT]: Make
	code unconditional.
	[!HAVE_FMA4_SUPPORT]: Remove conditional code.
	* sysdeps/x86_64/fpu/multiarch/s_fmaf.c [HAVE_FMA4_SUPPORT]: Make
	code unconditional.
	[!HAVE_FMA4_SUPPORT]: Remove conditional code.
	* sysdeps/x86_64/fpu/multiarch/s_sin.c [HAVE_FMA4_SUPPORT]: Make
	code unconditional.
	[!HAVE_FMA4_SUPPORT]: Remove conditional code.
	* sysdeps/x86_64/fpu/multiarch/s_tan.c [HAVE_FMA4_SUPPORT]: Make
	code unconditional.
	[!HAVE_FMA4_SUPPORT]: Remove conditional code.
	* config.h.in (HAVE_FMA4_SUPPORT): Remove #undef.
2015-10-09 16:02:54 +00:00
Joseph Myers 1b12cd7f4d Remove configure tests for AVX support.
GCC added support for -mavx and -msse2avx in version 4.4.  Thus the
configure tests for this support are obsolete, and this patch removes
them.

Tested for x86_64 and x86 (testsuite, and that installed stripped
shared libraries are unchanged by this patch).

	* sysdeps/i386/configure.ac (libc_cv_cc_avx): Remove configure
	test.
	(libc_cv_cc_sse2avx): Likewise.
	* sysdeps/i386/configure: Regenerated.
	* sysdeps/i386/i686/multiarch/Makefile
	[$(subdir)$(config-cflags-avx) = mathyes]: Change conditional to
	[$(subdir) = math].
	* sysdeps/i386/i686/multiarch/s_fma-fma.c [HAVE_AVX_SUPPORT]: Make
	code unconditional.
	* sysdeps/i386/i686/multiarch/s_fma.c [HAVE_AVX_SUPPORT]:
	Likewise.
	* sysdeps/i386/i686/multiarch/s_fmaf-fma.c [HAVE_AVX_SUPPORT]:
	Likewise.
	* sysdeps/i386/i686/multiarch/s_fmaf.c [HAVE_AVX_SUPPORT]:
	Likewise.
	* sysdeps/x86_64/configure.ac (libc_cv_cc_avx): Remove configure
	test.
	(libc_cv_cc_sse2avx): Likewise.
	* sysdeps/x86_64/configure: Regenerated.
	* sysdeps/x86_64/Makefile [$(config-cflags-avx) = yes]: Make code
	unconditional.
	* sysdeps/x86_64/dl-trampoline.h (_dl_runtime_profile)
	[HAVE_AVX_SUPPORT || HAVE_AVX512_ASM_SUPPORT]: Make code
	unconditional.
	(_dl_runtime_profile)
	[!(HAVE_AVX_SUPPORT || HAVE_AVX512_ASM_SUPPORT)]: Remove
	conditional code.
	* sysdeps/x86_64/fpu/multiarch/Makefile
	[$(config-cflags-sse2avx) = yes]: Make code unconditional.
	* sysdeps/x86_64/fpu/multiarch/e_atan2.c
	[HAVE_FMA4_SUPPORT || HAVE_AVX_SUPPORT]: Likewise.
	* sysdeps/x86_64/fpu/multiarch/e_exp.c
	[HAVE_FMA4_SUPPORT || HAVE_AVX_SUPPORT]: Likewise.
	* sysdeps/x86_64/fpu/multiarch/e_log.c
	[HAVE_FMA4_SUPPORT || HAVE_AVX_SUPPORT]: Likewise.
	* sysdeps/x86_64/fpu/multiarch/s_atan.c
	[HAVE_FMA4_SUPPORT || HAVE_AVX_SUPPORT]: Likewise.
	* sysdeps/x86_64/fpu/multiarch/s_fma.c [HAVE_AVX_SUPPORT]:
	Likewise.
	* sysdeps/x86_64/fpu/multiarch/s_fmaf.c [HAVE_AVX_SUPPORT]:
	Likewise.
	* sysdeps/x86_64/fpu/multiarch/s_sin.c
	[HAVE_FMA4_SUPPORT || HAVE_AVX_SUPPORT]: Likewise.
	* sysdeps/x86_64/fpu/multiarch/s_tan.c
	[HAVE_FMA4_SUPPORT || HAVE_AVX_SUPPORT]: Likewise.
	* sysdeps/x86_64/multiarch/strcmp.S [HAVE_AVX_SUPPORT]: Likewise.
	* config.h.in (HAVE_AVX_SUPPORT): Remove #undef.
	(HAVE_SSE2AVX_SUPPORT): Likewise.
2015-10-08 15:59:32 +00:00
Joseph Myers 3b7aa5bf59 Remove configure tests for SSE4 support.
GCC added support for -msse4 in version 4.3.  Thus the configure tests
for it are obsolete, and this patch removes them.

Tested for x86_64 and x86 (testsuite, and that installed stripped
shared libraries are unchanged by this patch).

	* sysdeps/i386/configure.ac (libc_cv_cc_sse4): Remove configure
	test.
	* sysdeps/i386/configure: Regenerated.
	* sysdeps/i386/i686/multiarch/Makefile
	[$(config-cflags-sse4) = yes]: Make code unconditional.
	* sysdeps/i386/i686/multiarch/strcspn.S [HAVE_SSE4_SUPPORT]:
	Likewise.
	* sysdeps/i386/i686/multiarch/strspn.S [HAVE_SSE4_SUPPORT]:
	Likewise.
	* sysdeps/x86_64/configure.ac (libc_cv_cc_sse4): Remove configure
	test.
	* sysdeps/x86_64/configure: Regenerated.
	* sysdeps/x86_64/multiarch/Makefile [$(config-cflags-sse4) = yes]:
	Make code unconditional.
	* sysdeps/x86_64/multiarch/strcspn.S [HAVE_SSE4_SUPPORT]:
	Likewise.
	* sysdeps/x86_64/multiarch/strspn.S [HAVE_SSE4_SUPPORT]: Likewise.
	* config.h.in (HAVE_SSE4_SUPPORT): Remove #undef.
2015-10-06 20:47:40 +00:00
Joseph Myers bc3753638a Work around powerpc32 integer 0 converting to -0 (bug 887, bug 19049, bug 19050).
On powerpc32 hard-float, older processors (ones where fcfid is not
available for 32-bit code), GCC generates conversions from integers to
floating point that wrongly convert integer 0 to -0 instead of +0 in
FE_DOWNWARD mode.  This in turn results in logb and a few other
functions wrongly returning -0 when they should return +0.

This patch works around this issue in glibc as I proposed in
<https://sourceware.org/ml/libc-alpha/2015-09/msg00728.html>, so that
the affected functions can be correct and the affected tests pass in
the absence of a GCC fix for this longstanding issue (GCC bug 67771 -
if fixed, of course we can put in GCC version conditionals, and
eventually phase out the workarounds).  A new macro
FIX_INT_FP_CONVERT_ZERO is added in a new sysdeps header
fix-int-fp-convert-zero.h, and the powerpc32/fpu version of that
header defines the macro based on the results of a configure test for
whether such conversions use the fcfid instruction.

Tested for x86_64 (that installed stripped shared libraries are
unchanged by the patch) and powerpc (that HAVE_PPC_FCFID comes out to
0 as expected and that the relevant tests are fixed).  Also tested a
build with GCC configured for -mcpu=power4 and verified that
HAVE_PPC_FCFID comes out to 1 in that case.

There are still some other issues to fix to get test-float and
test-double passing cleanly for older powerpc32 processors (apart from
the need for an ulps regeneration for powerpc).  (test-ldouble will be
harder to get passing cleanly, but with a combination of selected
fixes to ldbl-128ibm code that don't involve significant performance
issues, allowing spurious underflow and inexact exceptions for that
format, and lots of XFAILing for the default case of unpatched libgcc,
it should be doable.)

	[BZ #887]
	[BZ #19049]
	[BZ #19050]
	* sysdeps/generic/fix-int-fp-convert-zero.h: New file.
	* sysdeps/ieee754/dbl-64/e_log10.c: Include
	<fix-int-fp-convert-zero.h>.
	(__ieee754_log10): Adjust signs as needed if FIX_INT_FP_CONVERT_ZERO.
	* sysdeps/ieee754/dbl-64/e_log2.c: Include
	<fix-int-fp-convert-zero.h>.
	(__ieee754_log2): Adjust signs as needed if FIX_INT_FP_CONVERT_ZERO.
	* sysdeps/ieee754/dbl-64/s_erf.c: Include
	<fix-int-fp-convert-zero.h>.
	(__erfc): Adjust signs as needed if FIX_INT_FP_CONVERT_ZERO.
	* sysdeps/ieee754/dbl-64/s_logb.c: Include
	<fix-int-fp-convert-zero.h>.
	(__logb): Adjust signs as needed if FIX_INT_FP_CONVERT_ZERO.
	* sysdeps/ieee754/flt-32/e_log10f.c: Include
	<fix-int-fp-convert-zero.h>.
	(__ieee754_log10f): Adjust signs as needed if FIX_INT_FP_CONVERT_ZERO.
	* sysdeps/ieee754/flt-32/e_log2f.c: Include
	<fix-int-fp-convert-zero.h>.
	(__ieee754_log2f): Adjust signs as needed if FIX_INT_FP_CONVERT_ZERO.
	* sysdeps/ieee754/flt-32/s_erff.c: Include
	<fix-int-fp-convert-zero.h>.
	(__erfcf): Adjust signs as needed if FIX_INT_FP_CONVERT_ZERO.
	* sysdeps/ieee754/flt-32/s_logbf.c: Include
	<fix-int-fp-convert-zero.h>.
	(__logbf): Adjust signs as needed if FIX_INT_FP_CONVERT_ZERO.
	* sysdeps/ieee754/ldbl-128ibm/s_erfl.c: Include
	<fix-int-fp-convert-zero.h>.
	(__erfcl): Adjust signs as needed if FIX_INT_FP_CONVERT_ZERO.
	* sysdeps/ieee754/ldbl-128ibm/s_logbl.c: Include
	<fix-int-fp-convert-zero.h>.
	(__logbl): Adjust signs as needed if FIX_INT_FP_CONVERT_ZERO.
	* sysdeps/powerpc/powerpc32/fpu/configure.ac: New file.
	* sysdeps/powerpc/powerpc32/fpu/configure: New generated file.
	* sysdeps/powerpc/powerpc32/fpu/fix-int-fp-convert-zero.h: New
	file.
	* config.h.in [_LIBC] (HAVE_PPC_FCFID): New macro.
2015-10-05 17:46:50 +00:00
Stefan Liebler 4f0a1cea34 S390: configure check for vector instruction support in assembler.
The S390 specific test checks if the assembler has support for the new z13
vector instructions by compiling a vector instruction. The .machine and
.machinemode directives are needed to compile the vector instruction without
-march=z13 option on 31/64 bit.
On success the macro HAVE_S390_VX_ASM_SUPPORT is defined. This macro is used
to determine if the optimized functions can be build without compile errors.
If the used assembler lacks vector support, then a warning is dumped while
configuring and only the common code functions are build.

The z13 instruction support was introduced in
"[Committed] S/390: Add support for IBM z13."
(https://sourceware.org/ml/binutils/2015-01/msg00197.html)

ChangeLog:

	* config.h.in (HAVE_S390_VX_ASM_SUPPORT): New macro undefine.
	* sysdeps/s390/configure.ac: Add test for S390 vector instruction
	assembler support.
	* sysdeps/s390/configure: Regenerated.
2015-08-26 10:26:19 +02:00
Szabolcs Nagy 44cb254f9a [AArch64] Fix the big endian loader name. 2015-05-01 13:58:55 +01:00
Alan Modra 59261ad3eb Remove HAVE_ASM_PPC_REL16 references
In bc0cdc498 the configure check for HAVE_ASM_PPC_REL16 was removed
on the grounds that the minimum binutils supports rel16 relocs.  This
is true, but not all references to HAVE_ASM_PPC_REL16 in the sources
were removed.

	* config.h.in: Remove HAVE_ASM_PPC_REL16.
	* sysdeps/powerpc/powerpc32/tls-macros.h: Remove HAVE_ASM_PPC_REL16
	and false branch of conditional.
	* sysdeps/unix/sysv/linux/powerpc/powerpc32/swapcontext-common.S:
	Likewise.
2015-03-23 15:33:59 +10:30
Adhemerval Zanella 5ca10a0c9a powerpc: Remove HAVE_ASM_GLOBAL_DOT_NAME define
With AIX port deprecated there is no need to check/define
HAVE_ASM_GLOBAL_DOT_NAME anymore since the current minimum binutils
supported (2.22) does not emit global symbol with dot.

This patch removes all the HAVE_ASM_GLOBAL_DOT_NAME definition and
checks for powerpc64 port.
2015-03-11 09:01:05 -04:00
Roland McGrath 8c2b1ed8bb ARM: Use movw/movt more when available 2014-10-22 14:20:35 -07:00
Joseph Myers af296fcdab Remove bitrotten --enable-oldest-abi (bug 6652).
This patch removes the --enable-oldest-abi configure option, which has
long been bitrotten (as reported in bug 6652).  The principle of
removing this option was agreed in the thread starting at
<https://sourceware.org/ml/libc-alpha/2013-07/msg00174.html>.

Tested for x86_64 and x86 that the installed shared libraries other
than libc.so are unchanged by this patch and that libc.so disassembly
and symbol versions are unchanged (debug info changes because of
changed line numbers in csu/version.c).

	[BZ #6652]
	* Makeconfig (soversions-default-setname): Remove variable.
	($(common-objpfx)soversions.i): Don't pass default_setname to
	soversions.awk.
	* Makerules ($(common-objpfx)abi-versions.h): Don't pass
	oldest_abi to abi-versions.awk.
	* config.h.in (GLIBC_OLDEST_ABI): Remove macro undefine.
	* config.make.in (oldest-abi): Remove variable.
	* configure.ac (--enable-oldest-abi): Remove configure option.
	* configure: Regenerated.
	* csu/version.c (banner) [GLIBC_OLDEST_ABI]: Remove conditional
	text.
	* scripts/abi-versions.awk: Do not handle oldest_abi variable.
	* scripts/soversions.awk: Do not handle default_setname variable.
	* sysdeps/mach/hurd/configure.ac: Do not handle oldest_abi
	variable.
	* sysdeps/mach/hurd/configure: Regenerated.
	* sysdeps/unix/sysv/linux/configure.ac: Do not handle oldest_abi
	variable.
	* sysdeps/unix/sysv/linux/configure: Regenerated.
2014-09-16 17:45:03 +00:00
Joseph Myers 73a391126d Use %ifdef in sysdeps/unix/sysv/linux/powerpc/powerpc64/shlib-versions.
This patch makes
sysdeps/unix/sysv/linux/powerpc/powerpc64/shlib-versions use %ifdef
conditionals around the different symbol version definitions for big
and little endian.  (It doesn't actually change the host patterns used
for those definitions; the point is to make it possible to remove the
first column from shlib-versions by eliminating the last case where it
would be harmful for it to be treated as .*-.*-.*.)  The conditional
is based on the ELFv1/ELFv2 distinction rather than BE/LE, since
that's what's already tested in configure and used for the ld.so
soname in the Makefiles.  (Of course if BE ELFv2 were supported in
future, it would get new symbol versions and so need new
conditionals.)

	* sysdeps/unix/sysv/linux/powerpc/powerpc64/configure.ac
	(HAVE_ELFV2_ABI): AC_DEFINE in ELFv2 case.
	* sysdeps/unix/sysv/linux/powerpc/powerpc64/configure:
	Regenerated.
	* config.h.in (HAVE_ELFV2_ABI): New macro undefine.
	* sysdeps/unix/sysv/linux/powerpc/powerpc64/shlib-versions:
	Condition symbol version definitions on [HAVE_ELFV2_ABI].
2014-09-12 12:25:36 +00:00
Roland McGrath 9fe7e787ad Use __builtin_trap for ABORT_INSTRUCTION. 2014-07-31 13:07:19 -07:00
Andreas Schwab 6c9578a24b Fix -Wundef warning for HAVE_IFUNC 2014-07-31 17:05:19 +02:00
H.J. Lu f2fef657d8 Enable AVX2 optimized memset only if -mavx2 works
* config.h.in (HAVE_AVX2_SUPPORT): New #undef.
	* sysdeps/i386/configure.ac: Set HAVE_AVX2_SUPPORT and
	config-cflags-avx2.
	* sysdeps/x86_64/configure.ac: Likewise.
	* sysdeps/i386/configure: Regenerated.
	* sysdeps/x86_64/configure: Likewise.
	* sysdeps/x86_64/multiarch/Makefile (sysdep_routines): Add
	memset-avx2 only if config-cflags-avx2 is yes.
	* sysdeps/x86_64/multiarch/ifunc-impl-list.c (__libc_ifunc_impl_list):
	Tests for memset_chk and memset only if HAVE_AVX2_SUPPORT is
	defined.
	* sysdeps/x86_64/multiarch/memset.S: Define multiple versions
	only if HAVE_AVX2_SUPPORT is defined.
	* sysdeps/x86_64/multiarch/memset_chk.S: Likewise.
2014-07-14 07:58:27 -07:00
Joseph Myers a8779c28a8 Remove configure tests for assembler CFI support.
This patch removes configure tests for assembler CFI support (and
thereby eliminates an architecture-specific case in the main
configure.ac), instead assuming that support is present
unconditionally.

The main test was added in 2003 around the time CFI support was added
to the assembler.  cfi_personality and cfi_lsda support were added to
the assembler in 2006.  cfi_sections support was added in 2009, a few
weeks before binutils 2.20 was released; it's in 2.20, the minimum
supported version, so even that configure test is obsolete.

Tested x86_64 that the installed shared libraries are unchanged by
this patch.

	* configure.ac (libc_cv_asm_cfi_directives): Remove configure
	test.
	* configure: Regenerated.
	* config.h.in (HAVE_ASM_CFI_DIRECTIVES): Remove macro undefine.
	* sysdeps/arm/configure.ac (libc_cv_asm_cfi_directive_sections):
	Remove configure test.
	* sysdeps/arm/configure: Regenerated.
	* sysdeps/nptl/configure.ac: Do not check
	libc_cv_asm_cfi_directives.
	* sysdeps/nptl/configure: Regenerated.
	* sysdeps/x86_64/nptl/configure.ac: Remove file.
	* sysdeps/x86_64/nptl/configure: Remove generated file.
	* b/sysdeps/generic/sysdep.h [HAVE_ASM_CFI_DIRECTIVES]: Make code
	unconditional.
	[!HAVE_ASM_CFI_DIRECTIVES]: Remove conditional code.
2014-06-26 17:33:32 +00:00
Joseph Myers 92072d57c6 Remove BROKEN_PPC_ASM_CR0 configure test.
One piece of architecture-specific code in the main configure.ac is
the powerpc test that can define BROKEN_PPC_ASM_CR0.  There's no need
to move this to a sysdeps configure script, or to work out what bug it
was testing in May 1998 to see if it's still relevant, since nothing
in the source tree now uses the results of this test.  Thus, this
patch just removes the test in question.

Not tested.

	* configure.ac (libc_cv_c_asmcr0_bug): Remove configure test.
	* configure: Regenerated.
	* config.h.in (BROKEN_PPC_ASM_CR0): Remove macro.
2014-06-25 17:54:44 +00:00
Andreas Schwab 73ba67cbc3 Fix macro warning on HAVE_PT_CHOWN 2014-05-14 09:46:54 +02:00
Igor Zamyatin a4c75cfd56 Save/restore bound registers in _dl_runtime_resolve
This patch saves and restores bound registers in symbol lookup for x86-64:

1. Branches without BND prefix clear bound registers.
2. x86-64 pass bounds in bound registers as specified in MPX psABI
extension on hjl/mpx/master branch at

https://github.com/hjl-tools/x86-64-psABI
https://groups.google.com/forum/#!topic/x86-64-abi/KFsB0XTgWYc

Binutils has been updated to create an alternate PLT to add BND prefix
when branching to ld.so.

	* config.h.in (HAVE_MPX_SUPPORT): New #undef.
	* sysdeps/x86_64/configure.ac: Set HAVE_MPX_SUPPORT.
	* sysdeps/x86_64/configure: Regenerated.
	* sysdeps/x86_64/dl-trampoline.S (REGISTER_SAVE_AREA): New
	macro.
	(REGISTER_SAVE_RAX): Likewise.
	(REGISTER_SAVE_RCX): Likewise.
	(REGISTER_SAVE_RDX): Likewise.
	(REGISTER_SAVE_RSI): Likewise.
	(REGISTER_SAVE_RDI): Likewise.
	(REGISTER_SAVE_R8): Likewise.
	(REGISTER_SAVE_R9): Likewise.
	(REGISTER_SAVE_BND0): Likewise.
	(REGISTER_SAVE_BND1): Likewise.
	(REGISTER_SAVE_BND2): Likewise.
	(_dl_runtime_resolve): Use them.  Save and restore Intel MPX
	bound registers when calling _dl_fixup.
2014-04-09 15:38:09 -07:00
Igor Zamyatin 2d63a517e4 Save and restore AVX-512 zmm registers to x86-64 ld.so
AVX-512 ISA adds 512-bit zmm registers.  This patch updates
_dl_runtime_profile to pass zmm registers to run-time audit. It also
changes _dl_x86_64_save_sse and _dl_x86_64_restore_sse to upport zmm
registers, which are called when only when RTLD_PREPARE_FOREIGN_CALL
is used.  Its performance impact is minimum.

	* config.h.in (HAVE_AVX512_SUPPORT): New #undef.
	(HAVE_AVX512_ASM_SUPPORT): Likewise.
	* sysdeps/x86_64/bits/link.h (La_x86_64_zmm): New.
	(La_x86_64_vector): Add zmm.
	* sysdeps/x86_64/Makefile (tests): Add tst-audit10.
	(modules-names): Add tst-auditmod10a and tst-auditmod10b.
	($(objpfx)tst-audit10): New target.
	($(objpfx)tst-audit10.out): Likewise.
	(tst-audit10-ENV): New.
	(AVX512-CFLAGS): Likewise.
	(CFLAGS-tst-audit10.c): Likewise.
	(CFLAGS-tst-auditmod10a.c): Likewise.
	(CFLAGS-tst-auditmod10b.c): Likewise.
	* sysdeps/x86_64/configure.ac: Set config-cflags-avx512,
	HAVE_AVX512_SUPPORT and HAVE_AVX512_ASM_SUPPORT.
	* sysdeps/x86_64/configure: Regenerated.
	* sysdeps/x86_64/dl-trampoline.S (_dl_runtime_profile): Add
	AVX-512 zmm register support.
	(_dl_x86_64_save_sse): Likewise.
	(_dl_x86_64_restore_sse): Likewise.
	* sysdeps/x86_64/dl-trampoline.h: Updated to support different
	size vector registers.
	* sysdeps/x86_64/link-defines.sym (YMM_SIZE): New.
	(ZMM_SIZE): Likewise.
	* sysdeps/x86_64/tst-audit10.c: New file.
	* sysdeps/x86_64/tst-auditmod10a.c: Likewise.
	* sysdeps/x86_64/tst-auditmod10b.c: Likewise.
2014-03-13 11:19:08 -07:00
Roland McGrath 44c4e5d598 Use __ehdr_start, when available, for rtld to get its own headers. 2014-03-13 10:38:27 -07:00
Mike Frysinger 20f4a8d993 tst-fanotify: switch to AC_DEFINE
Reported-by: Joseph S. Myers <joseph@codesourcery.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2014-01-04 08:34:01 -05:00
Mike Frysinger cb8a6dbd17 rename configure.in to configure.ac
Autoconf has been deprecating configure.in for quite a long time.
Rename all our configure.in and preconfigure.in files to .ac.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2013-10-30 17:32:08 +10:00
Maciej W. Rozycki 9c21573c02 MIPS: IEEE 754-2008 NaN encoding support
It has been a long practice for software using IEEE 754 floating-point
arithmetic run on MIPS processors to use an encoding of Not-a-Number
(NaN) data different to one used by software run on other processors.
And as of IEEE 754-2008 revision [1] this encoding does not follow one
recommended in the standard, as specified in section 6.2.1, where it
is stated that quiet NaNs should have the first bit (d1) of their
significand set to 1 while signalling NaNs should have that bit set to
0, but MIPS software interprets the two bits in the opposite manner.

As from revision 3.50 [2][3] the MIPS Architecture provides for
processors that support the IEEE 754-2008 preferred NaN encoding format.
As the two formats (further referred to as "legacy NaN" and "2008 NaN")
are incompatible to each other, tools have to provide support for the
two formats to help people avoid using incompatible binary modules.

The change is comprised of two functional groups of features, both of
which are required for correct support.

1. Dynamic linker support.

   To enforce the NaN encoding requirement in dynamic linking a new ELF
   file header flag has been defined.  This flag is set for 2008-NaN
   shared modules and executables and clear for legacy-NaN ones.  The
   dynamic linker silently ignores any incompatible modules it
   encounters in dependency processing.

   To avoid unnecessary processing of incompatible modules in the
   presence of a shared module cache, a set of new cache flags has been
   defined to mark 2008-NaN modules for the three ABIs supported.
   Changes to sysdeps/unix/sysv/linux/mips/readelflib.c have been made
   following an earlier code quality suggestion made here:

   http://sourceware.org/ml/libc-ports/2009-03/msg00036.html

   and are therefore a little bit more extensive than the minimum
   required.

   Finally a new name has been defined for the dynamic linker so that
   2008-NaN and legacy-NaN binaries can coexist on a single system that
   supports dual-mode operation and that a legacy dynamic linker that
   does not support verifying the 2008-NaN ELF file header flag is not
   chosen to interpret a 2008-NaN binary by accident.

2. Floating environment support.

   IEEE 754-2008 features are controlled in the Floating-Point Control
   and Status (FCSR) register and updates are needed to floating
   environment support so that the 2008-NaN flag is set correctly and
   the kernel default, inferred from the 2008-NaN ELF file header flag
   at the time an executable is loaded, respected.

As the NaN encoding format is a property of GCC code generation that is
both a user-selected GCC configuration default and can be overridden
with GCC options, code that needs to know what NaN encoding standard it
has been configured for checks for the __mips_nan2008 macro that is
defined internally by GCC whenever the 2008-NaN mode has been selected.
This mode is determined at the glibc configuration time and therefore a
few consistency checks have been added to catch cases where compilation
flags have been overridden by the user.

The 2008 NaN set of features relies on kernel support as the in-kernel
floating-point emulator needs to be aware of the NaN encoding used even
on hard-float processors and configure the FPU context according to the
value of the 2008 NaN ELF file header flag of the executable being
started.  As at this time work on kernel support is still in progress
and the relevant changes have not made their way yet to linux.org master
repository.

Therefore the minimum version supported has been artificially set to
10.0.0 so that 2008-NaN code is not accidentally run on a Linux kernel
that does not suppport it.  It is anticipated that the version is
adjusted later on to the actual initial linux.org kernel version to
support this feature.  Legacy NaN encoding support is unaffected, older
kernel versions remain supported.

[1] "IEEE Standard for Floating-Point Arithmetic", IEEE Computer
    Society, IEEE Std 754-2008, 29 August 2008

[2] "MIPS Architecture For Programmers, Volume I-A: Introduction to the
    MIPS32 Architecture", MIPS Technologies, Inc., Document Number:
    MD00082, Revision 3.50, September 20, 2012

[3] "MIPS Architecture For Programmers, Volume I-A: Introduction to the
    MIPS64 Architecture", MIPS Technologies, Inc., Document Number:
    MD00083, Revision 3.50, September 20, 2012
2013-09-18 21:33:50 +01:00
Joseph Myers 3f2e46a494 Remove --disable-versioning. 2013-09-04 15:25:42 +00:00
Carlos O'Donell e4608715e6 CVE-2013-2207, BZ #15755: Disable pt_chown.
The helper binary pt_chown tricked into granting access to another
user's pseudo-terminal.

Pre-conditions for the attack:

 * Attacker with local user account
 * Kernel with FUSE support
 * "user_allow_other" in /etc/fuse.conf
 * Victim with allocated slave in /dev/pts

Using the setuid installed pt_chown and a weak check on whether a file
descriptor is a tty, an attacker could fake a pty check using FUSE and
trick pt_chown to grant ownership of a pty descriptor that the current
user does not own.  It cannot access /dev/pts/ptmx however.

In most modern distributions pt_chown is not needed because devpts
is enabled by default. The fix for this CVE is to disable building
and using pt_chown by default. We still provide a configure option
to enable hte use of pt_chown but distributions do so at their own
risk.
2013-07-21 15:39:55 -04:00
Andi Kleen 1717da59ae Add a configure option to enable lock elision and disable by default
Can be enabled with --enable-lock-elision=yes at configure time.
2013-07-02 08:46:55 -07:00
Adhemerval Zanella 85c2e6110c Fix loop construction to functions calls
Check wheter the compiler has the option -fno-tree-loop-distribute-patterns
to inhibit loop transformation to library calls and uses it on memset
and memmove default implementation to avoid recursive calls.
2013-06-20 19:42:05 -05:00
Joseph Myers 2bdd4ca6b6 Remove miscellaneous bounded-pointers relics in C code. 2013-02-15 00:51:53 +00:00
Joseph Myers 8b748aed2a Support --with-pkgversion and --with-bugurl. 2012-11-09 22:13:45 +00:00
Roland McGrath 6e6249d0b4 BZ#14743: Move clock_* symbols from librt to libc. 2012-10-24 14:50:46 -07:00
Roland McGrath f57f805541 Clean up conditionalize of ld.so.cache support. 2012-10-03 16:13:14 -07:00
Roland McGrath 3cc3ef96d6 BZ#13696: Add --disable-nscd configure option. 2012-08-22 13:31:12 -07:00
Mike Frysinger ca98e1710e i386/x86_64: punt HAVE_CPP_ASM_DEBUGINFO
Pretty sure we require recent enough versions of gcc/binutils to make this
check pointless.  I can't any logs in the last few years where this check
didn't return "yes".

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2012-08-14 21:37:00 -04:00
Marek Polacek b67e9372b2 Get rid of ASM_TYPE_DIRECTIVE{,_PREFIX}. 2012-08-02 21:04:29 +02:00
Marek Polacek 7b8e0d49cb Get rid of ASM_GLOBAL_DIRECTIVE. 2012-07-10 14:30:24 +02:00