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Adhemerval Zanella 06ab719d30 Fix Linux fcntl OFD locks for non-LFS architectures (BZ#20251)
This patch fixes the OFD ("file private") locks for architectures that
support non-LFS flock definition (__USE_FILE_OFFSET64 not defined). The
issue in this case is both F_OFD_{GETLK,SETLK,SETLKW} and
F_{SET,GET}L{W}K64 expects a flock64 argument and when using old
F_OFD_* flags with a non LFS flock argument the kernel might interpret
the underlying data wrongly.  Kernel idea originally was to avoid using
such flags in non-LFS syscall, but since GLIBC uses fcntl with LFS
semantic as default it is possible to provide the functionality and
avoid the bogus struct kernel passing by adjusting the struct manually
for the required flags.

The idea follows other LFS interfaces that provide two symbols:

  1. A new LFS fcntl64 is added on default ABI with the usual macros to
     select it for FILE_OFFSET_BITS=64.

  2. The Linux non-LFS fcntl use a stack allocated struct flock64 for
     F_OFD_{GETLK,SETLK,SETLKW} copy the results on the user provided
     struct.

  3. Keep a compat symbol with old broken semantic for architectures
     that do not define __OFF_T_MATCHES_OFF64_T.

So for architectures which defines __USE_FILE_OFFSET64, fcntl64 will
aliased to fcntl and no adjustment would be required.  So to actually
use F_OFD_* with LFS support the source must be built with LFS support
(_FILE_OFFSET_BITS=64).

Also F_OFD_SETLKW command is handled a cancellation point, as for
F_SETLKW{64}.

Checked on x86_64-linux-gnu and i686-linux-gnu.

	[BZ #20251]
	* NEWS: Mention fcntl64 addition.
	* csu/check_fds.c: Replace __fcntl_nocancel by __fcntl64_nocancel.
	* login/utmp_file.c: Likewise.
	* sysdeps/posix/fdopendir.c: Likewise.
	* sysdeps/posix/opendir.c: Likewise.
	* sysdeps/unix/pt-fcntl.c: Likewise.
	* include/fcntl.h (__libc_fcntl64, __fcntl64,
	__fcntl64_nocancel_adjusted): New prototype.
	(__fcntl_nocancel_adjusted): Remove prototype.
	* io/Makefile (routines): Add fcntl64.
	(CFLAGS-fcntl64.c): New rule.
	* io/Versions [GLIBC_2.28] (fcntl64): New symbol.
	[GLIBC_PRIVATE] (__libc_fcntl): Rename to __libc_fcntl64.
	* io/fcntl.h (fcntl64): Add prototype and redirect if
	__USE_FILE_OFFSET64 is defined.
	* io/fcntl64.c: New file.
	* manual/llio.text: Add a note for which commands fcntl acts a
	cancellation point.
	* nptl/Makefile (CFLAGS-fcntl64.c): New rule.
	* sysdeps/mach/hurd/fcntl.c: Alias fcntl to fcntl64 symbols.
	* sysdeps/mach/hurd/i386/libc.abilist [GLIBC_2.28] (fcntl, fcntl64):
	New symbols.
	* sysdeps/unix/sysv/linux/fcntl.c (__libc_fcntl): Fix F_GETLK64,
	F_OFD_GETLK, F_SETLK64, F_SETLKW64, F_OFD_SETLK, and F_OFD_SETLKW for
	non-LFS case.
	* sysdeps/unix/sysv/linux/fcntl64.c: New file.
	* sysdeps/unix/sysv/linux/fcntl_nocancel.c (__fcntl_nocancel): Rename
	to __fcntl64_nocancel.
	(__fcntl_nocancel_adjusted): Rename to __fcntl64_nocancel_adjusted.
	* sysdeps/unix/sysv/linux/not-cancel.h (__fcntl_nocancel): Rename
	to __fcntl64_nocancel.
	* sysdeps/unix/sysv/linux/tst-ofdlocks.c: New file.
	* sysdeps/unix/sysv/linux/tst-ofdlocks-compat.c: Likewise.
	* sysdeps/unix/sysv/linux/Makefile (tests): Add tst-ofdlocks.
	(tests-internal): Add tst-ofdlocks-compat.
	* sysdeps/unix/sysv/linux/aarch64/libc.abilist [GLIBC_2.28]
	(fcntl64): New symbol.
	* sysdeps/unix/sysv/linux/alpha/libc.abilist: Likewise.
	* sysdeps/unix/sysv/linux/ia64/libc.abilist: Likewise.
	* sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist: Likewise.
	* sysdeps/unix/sysv/linux/powerpc/powerpc64/libc.abilist: Likewise.
	* sysdeps/unix/sysv/linux/powerpc/powerpc64/libc-le.abilist: Likewise.
	* sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist: Likewise.
	* sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist: Likewise.
	* sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist: Likewise.
	* sysdeps/unix/sysv/linux/x86_64/64/libc.abilist: Likewise.
	* sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist: Likewise.
	* sysdeps/unix/sysv/linux/arm/libc.abilist [GLIBC_2.28] (fcntl,
	fcntl64): Likewise.
	* sysdeps/unix/sysv/linux/hppa/libc.abilist: Likewise.
	* sysdeps/unix/sysv/linux/i386/libc.abilis: Likewise.
	* sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist: Likewise.
	* sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist: Likewise.
	* sysdeps/unix/sysv/linux/microblaze/libc.abilist: Likewise.
	* sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist: Likewise.
	* sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist: Likewise.
	* sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist: Likewise.
	* sysdeps/unix/sysv/linux/nios2/libc.abilist: Likewise.
	* sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist:
	Likewise.
	* sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist:
	Likewise.
	* sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist: Likewise.
	* sysdeps/unix/sysv/linux/sh/libc.abilist: Likewise.
	* sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist: Likewise.
2018-06-26 13:22:53 -03:00
ChangeLog.old
argp
assert Fix uninitialized variable in assert_perror (bug 22761) 2018-02-05 11:06:15 +01:00
benchtests benchtests: Add -f/--functions argument 2018-06-12 09:10:42 -07:00
bits hurd: Fix shmid_ds's shm_segsz field type 2018-06-02 21:52:43 +02:00
catgets intl/tst-gettext: fix failure with newest msgfmt 2018-02-18 18:16:05 +01:00
conform hurd xfails: Add missing bug references 2018-04-20 17:14:13 +02:00
crypt
csu Fix Linux fcntl OFD locks for non-LFS architectures (BZ#20251) 2018-06-26 13:22:53 -03:00
ctype Use libc_hidden_* for tolower, toupper (bug 15105). 2018-02-23 13:54:53 +00:00
debug libio: Avoid _allocate_buffer, _free_buffer function pointers [BZ #23236] 2018-06-01 10:41:03 +02:00
dirent Consolidate alphasort{64} and versionsort{64} implementation 2018-04-23 17:35:16 -03:00
dlfcn
elf Add Andes nds32 dynamic relocations to elf.h 2018-06-21 20:44:43 +00:00
gmon
gnulib
grp
gshadow
hesiod
htl hurd: Fix missing __pthread_get_cleanup_stack symbol 2018-06-16 10:52:04 +02:00
hurd hurd: Silence warning 2018-04-04 02:06:16 +02:00
iconv Fix s390 -Os iconv build. 2018-03-05 21:46:55 +00:00
iconvdata localedata: Make IBM273 compatible with ISO-8859-1 [BZ #23290] 2018-06-14 22:34:10 +02:00
include Fix Linux fcntl OFD locks for non-LFS architectures (BZ#20251) 2018-06-26 13:22:53 -03:00
inet Switch IDNA implementation to libidn2 [BZ #19728] [BZ #19729] [BZ #22247] 2018-05-23 15:27:24 +02:00
intl intl/tst-gettext: fix failure with newest msgfmt 2018-02-18 18:16:05 +01:00
io Fix Linux fcntl OFD locks for non-LFS architectures (BZ#20251) 2018-06-26 13:22:53 -03:00
libio libio: Add tst-vtables, tst-vtables-interposed 2018-06-26 12:31:08 +02:00
locale Fix two more -Os strcoll / wcscoll build failures. 2018-02-27 16:55:42 +00:00
localedata csb_PL: Add alternative month names (bug 23140). 2018-06-25 12:34:31 +02:00
login Fix Linux fcntl OFD locks for non-LFS architectures (BZ#20251) 2018-06-26 13:22:53 -03:00
mach hurd: Avoid PLT references to syscalls 2018-06-16 02:50:36 +02:00
malloc Run thread shutdown functions in an explicit order 2018-06-26 15:27:12 +02:00
manual Fix Linux fcntl OFD locks for non-LFS architectures (BZ#20251) 2018-06-26 13:22:53 -03:00
math Add a generic significand implementation 2018-06-20 18:15:06 -03:00
mathvec
misc Implement allocate_once for atomic initialization with allocation 2018-05-23 15:27:01 +02:00
nis _nss_nis_initgroups_dyn: Use struct scratch_buffer [BZ #18023] 2018-06-25 19:14:09 +02:00
nptl Fix Linux fcntl OFD locks for non-LFS architectures (BZ#20251) 2018-06-26 13:22:53 -03:00
nptl_db nptl_db: Remove stale `match_pid' parameter from `iterate_thread_list' 2018-03-01 16:10:05 +00:00
nscd nscd: Switch to struct scratch_buffer in adhstaiX [BZ #18023] 2018-06-25 18:41:54 +02:00
nss nss_files: Use struct scratch_buffer instead of extend_alloca [BZ #18023] 2018-06-25 19:48:01 +02:00
po Update translations from the Translation Project 2018-03-12 13:24:46 +00:00
posix Avoid cancellable I/O primitives in ld.so. 2018-06-12 09:53:04 -04:00
pwd
resolv Run thread shutdown functions in an explicit order 2018-06-26 15:27:12 +02:00
resource
rt hurd: Add hurd thread library 2018-04-02 01:44:14 +02:00
scripts scripts/update-abilist.sh: Accept empty list of files to patch 2018-06-14 09:37:31 +02:00
setjmp x86: Use pad in pthread_unwind_buf to preserve shadow stack register 2018-05-02 06:17:41 -07:00
shadow
signal Add tst-sigaction.c to test BZ #23069 2018-04-26 22:21:13 +02:00
socket
soft-fp Make powerpc-nofpu __sqrtsf2, __sqrtdf2 compat symbols (bug 18473). 2018-06-01 17:25:12 +00:00
stdio-common Fix scanf rounding of negative floating-point numbers (bug 23280). 2018-06-19 11:52:18 +00:00
stdlib Add tests for sign of NaN returned by strtod (bug 23007). 2018-06-15 17:36:21 +00:00
streams
string Run thread shutdown functions in an explicit order 2018-06-26 15:27:12 +02:00
sunrpc Run thread shutdown functions in an explicit order 2018-06-26 15:27:12 +02:00
support support: Add TEST_NO_SETVBUF 2018-06-26 12:30:50 +02:00
sysdeps Fix Linux fcntl OFD locks for non-LFS architectures (BZ#20251) 2018-06-26 13:22:53 -03:00
sysvipc
termios
time Fix year 2039 bug for localtime with 64-bit time_t (bug 22639). 2018-05-18 11:57:15 +00:00
timezone
wcsmbs Add tests for sign of NaN returned by strtod (bug 23007). 2018-06-15 17:36:21 +00:00
wctype
.gitattributes
.gitignore
COPYING
COPYING.LIB
ChangeLog Fix Linux fcntl OFD locks for non-LFS architectures (BZ#20251) 2018-06-26 13:22:53 -03:00
INSTALL Document use of CC and CFLAGS in more detail (bug 20980, bug 21234). 2018-02-15 23:48:47 +00:00
LICENSES Switch IDNA implementation to libidn2 [BZ #19728] [BZ #19729] [BZ #22247] 2018-05-23 15:27:24 +02:00
MAINTAINERS
Makeconfig Add support for sqrt asm redirects 2018-03-15 19:21:35 +00:00
Makefile
Makefile.in
Makerules Run thread shutdown functions in an explicit order 2018-06-26 15:27:12 +02:00
NEWS Fix Linux fcntl OFD locks for non-LFS architectures (BZ#20251) 2018-06-26 13:22:53 -03:00
README Remove tilegx port. 2018-04-27 19:11:24 +00:00
Rules
abi-tags
aclocal.m4
config.h.in Switch IDNA implementation to libidn2 [BZ #19728] [BZ #19729] [BZ #22247] 2018-05-23 15:27:24 +02:00
config.make.in
configure
configure.ac
extra-lib.mk
gen-locales.mk Improve gen-locales.mk and gen-locale.sh to make test files with @ options work 2018-02-27 17:01:57 +01:00
libc-abis
libof-iterator.mk
o-iterator.mk
shlib-versions
test-skeleton.c
version.h Open master branch for glibc 2.28 development 2018-02-01 17:18:19 +00:00

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