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Fangrui Song e555954e02 Revert "[AArch64][BZ #17711] Fix extern protected data handling"
This reverts commit 0910702c4d.

Say both a.so and b.so define protected data symbol `var` and the executable
copy relocates var.  ELF_RTYPE_CLASS_EXTERN_PROTECTED_DATA has strange
semantics: a.so accesses the copy in the executable while b.so accesses its
own.  This behavior requires that (a) the compiler emits GOT-generating
relocations (b) the linker produces GLOB_DAT instead of RELATIVE.

Without the ELF_RTYPE_CLASS_EXTERN_PROTECTED_DATA code, b.so's GLOB_DAT
will bind to the executable (normal behavior).

For aarch64 it makes sense to restore the original behavior and don't
pay the ELF_RTYPE_CLASS_EXTERN_PROTECTED_DATA cost.  The behavior is very
unlikely used by anyone.

* Clang code generator treats STV_PROTECTED the same way as STV_HIDDEN:
  no GOT-generating relocation in the first place.
* gold and lld reject copy relocation on a STV_PROTECTED symbol.
* Nowadays -fpie/-fpic modes are popular.  GCC/Clang's codegen uses
  GOT-generating relocation when accessing an default visibility
  external symbol which avoids copy relocation.

Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
2022-05-23 13:37:05 -07:00
argp Update copyright dates with scripts/update-copyrights 2022-01-01 11:40:24 -08:00
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benchtests elf: Optimize _dl_new_hash in dl-new-hash.h 2022-05-23 10:38:40 -05:00
bits elf: Issue la_symbind for bind-now (BZ #23734) 2022-02-01 14:49:46 -03:00
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ChangeLog.old Create ChangeLog.old/ChangeLog.24. 2022-02-03 00:27:54 -05:00
conform hurd: drop SA_SIGINFO availability xfail 2022-01-15 17:43:07 +01:00
crypt crypt: Remove unused variable on cert test 2022-03-31 09:00:54 -03:00
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debug wcrtomb: Make behavior POSIX compliant 2022-05-13 19:15:46 +05:30
dirent associate a deallocation for opendir 2022-03-14 20:02:46 +05:30
dlfcn dlfcn: Move RTLD_DEFAULT/RTLD_NEXT outside __USE_GNU 2022-05-23 10:23:23 -07:00
elf elf: Rewrite long RESOLVE_MAP macro to an always_inline static function 2022-05-23 12:06:44 -07:00
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htl htl: Destroy thread-specific data before releasing joins 2022-02-14 19:29:02 +01:00
hurd Replace {u}int_fast{16|32} with {u}int32_t 2022-04-13 21:23:04 -05:00
iconv Replace {u}int_fast{16|32} with {u}int32_t 2022-04-13 21:23:04 -05:00
iconvdata Replace {u}int_fast{16|32} with {u}int32_t 2022-04-13 21:23:04 -05:00
include stdio: Remove the usage of $(fno-unit-at-a-time) for siglist.c 2022-05-13 10:54:41 -03:00
inet inet: Return EAI_MEMORY when nrl_domainname() fails to allocate memory 2022-03-08 12:51:29 -03:00
intl intl: Avoid -Wuse-after-free [BZ #26779] 2022-01-25 17:38:31 -07:00
io linux: Fix fchmodat with AT_SYMLINK_NOFOLLOW for 64 bit time_t (BZ#29097) 2022-04-28 09:58:44 -03:00
libio libio: Flush-only _IO_str_overflow must not return EOF (bug 28949) 2022-03-18 21:40:02 +01:00
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login Update copyright dates not handled by scripts/update-copyrights. 2022-01-01 11:42:26 -08:00
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malloc malloc: Fix duplicate inline for do_set_mxfast 2022-03-23 12:28:44 -03:00
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rt rt/tst-mqueue*: Return UNSUPPORTED when mq_open fails with ENOSYS 2022-01-17 19:17:41 +01:00
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stdlib stdlib: Reflow and sort most variable assignments 2022-04-13 16:52:39 -03:00
string string.h: fix __fortified_attr_access macro call [BZ #29162] 2022-05-23 13:56:43 +05:30
sunrpc CVE-2022-23218: Buffer overflow in sunrpc svcunix_create (bug 28768) 2022-01-17 10:47:58 +01:00
support support: Add xmkfifo 2022-04-15 09:59:33 -03:00
sysdeps Revert "[AArch64][BZ #17711] Fix extern protected data handling" 2022-05-23 13:37:05 -07:00
sysvipc Update copyright dates with scripts/update-copyrights 2022-01-01 11:40:24 -08:00
termios posix: Add terminal control setting support for posix_spawn 2022-01-25 14:07:53 -03:00
time locale: Remove private union from struct __locale_data 2022-05-23 11:06:31 +02:00
timezone timezone: Fix tst-bz28707 Makefile rule 2022-01-12 10:30:10 -03:00
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aclocal.m4 Properly check linker option in LIBC_LINKER_FEATURE [BZ #28738] 2022-01-03 05:12:34 -08:00
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version.h Open master branch for glibc 2.36 development 2022-02-03 01:21:33 -05:00

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