glibc/sysdeps/unix/sysv/linux/fcntl64.c

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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.
2018-04-04 14:24:15 +00:00
/* Manipulate file descriptor. Linux LFS version.
Copyright (C) 2018-2019 Free Software Foundation, Inc.
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.
2018-04-04 14:24:15 +00:00
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#define fcntl __no_decl_fcntl
#define __fcntl __no_decl___fcntl
#include <fcntl.h>
#undef fcntl
#undef __fcntl
#include <stdarg.h>
#include <errno.h>
#include <sysdep-cancel.h>
#ifndef __NR_fcntl64
# define __NR_fcntl64 __NR_fcntl
#endif
#ifndef FCNTL_ADJUST_CMD
# define FCNTL_ADJUST_CMD(__cmd) __cmd
#endif
int
__libc_fcntl64 (int fd, int cmd, ...)
{
va_list ap;
void *arg;
va_start (ap, cmd);
arg = va_arg (ap, void *);
va_end (ap);
cmd = FCNTL_ADJUST_CMD (cmd);
if (cmd == F_SETLKW || cmd == F_SETLKW64 || cmd == F_OFD_SETLKW)
return SYSCALL_CANCEL (fcntl64, fd, cmd, arg);
return __fcntl64_nocancel_adjusted (fd, cmd, arg);
}
libc_hidden_def (__libc_fcntl64)
weak_alias (__libc_fcntl64, __fcntl64)
libc_hidden_weak (__fcntl64)
weak_alias (__libc_fcntl64, fcntl64)
#ifdef __OFF_T_MATCHES_OFF64_T
weak_alias (__libc_fcntl64, __libc_fcntl)
weak_alias (__libc_fcntl64, __fcntl)
weak_alias (__libc_fcntl64, __GI___fcntl)
weak_alias (__libc_fcntl64, fcntl)
#endif