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	Both open and openat load their last argument 'mode' lazily, using va_arg() only if O_CREAT is found in oflag. This is wrong, mode is also necessary if O_TMPFILE is in oflag. By chance on x86_64, the problem wasn't evident when using O_TMPFILE with open, as the 3rd argument of open, even when not loaded with va_arg, is left untouched in RDX, where the syscall expects it. However, openat was not so lucky, and O_TMPFILE couldn't be used: mode is the 4th argument, in RCX, but the syscall expects its 4th argument in a different register than the glibc wrapper, in R10. Introduce a macro __OPEN_NEEDS_MODE (oflag) to test if either O_CREAT or O_TMPFILE is set in oflag. Tested on Linux x86_64. [BZ #17523] * io/fcntl.h (__OPEN_NEEDS_MODE): New macro. * io/bits/fcntl2.h (open): Use it. (openat): Likewise. * io/open.c (__libc_open): Likewise. * io/open64.c (__libc_open64): Likewise. * io/open64_2.c (__open64_2): Likewise. * io/open_2.c (__open_2): Likewise. * io/openat.c (__openat): Likewise. * io/openat64.c (__openat64): Likewise. * io/openat64_2.c (__openat64_2): Likewise. * io/openat_2.c (__openat_2): Likewise. * sysdeps/mach/hurd/open.c (__libc_open): Likewise. * sysdeps/mach/hurd/openat.c (__openat): Likewise. * sysdeps/posix/open64.c (__libc_open64): Likewise. * sysdeps/unix/sysv/linux/dl-openat64.c (openat64): Likewise. * sysdeps/unix/sysv/linux/generic/open.c (__libc_open): Likewise. (__open_nocancel): Likewise. * sysdeps/unix/sysv/linux/generic/open64.c (__libc_open64): Likewise. * sysdeps/unix/sysv/linux/open64.c (__libc_open64): Likewise. * sysdeps/unix/sysv/linux/openat.c (__OPENAT): Likewise.
		
			
				
	
	
		
			72 lines
		
	
	
		
			1.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			72 lines
		
	
	
		
			1.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/* Copyright (C) 2011-2015 Free Software Foundation, Inc.
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   This file is part of the GNU C Library.
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   Contributed by Chris Metcalf <cmetcalf@tilera.com>, 2011.
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   The GNU C Library is free software; you can redistribute it and/or
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   modify it under the terms of the GNU Lesser General Public
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   License as published by the Free Software Foundation; either
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   version 2.1 of the License, or (at your option) any later version.
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   The GNU C Library is distributed in the hope that it will be useful,
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   but WITHOUT ANY WARRANTY; without even the implied warranty of
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   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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   Lesser General Public License for more details.
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   You should have received a copy of the GNU Lesser General Public
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   License along with the GNU C Library.  If not, see
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   <http://www.gnu.org/licenses/>.  */
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#include <errno.h>
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#include <fcntl.h>
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#include <stdarg.h>
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#include <stdio.h>
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#include <sysdep-cancel.h>
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/* Open FILE with access OFLAG.  If O_CREAT or O_TMPFILE is in OFLAG,
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   a third argument is the file protection.  */
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int
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__libc_open (const char *file, int oflag, ...)
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{
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  int mode = 0;
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  if (__OPEN_NEEDS_MODE (oflag))
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    {
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      va_list arg;
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      va_start (arg, oflag);
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      mode = va_arg (arg, int);
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      va_end (arg);
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    }
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  if (SINGLE_THREAD_P)
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    return INLINE_SYSCALL (openat, 4, AT_FDCWD, file, oflag, mode);
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  int oldtype = LIBC_CANCEL_ASYNC ();
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  int result = INLINE_SYSCALL (openat, 4, AT_FDCWD, file, oflag, mode);
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  LIBC_CANCEL_RESET (oldtype);
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  return result;
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}
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libc_hidden_def (__libc_open)
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weak_alias (__libc_open, __open)
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libc_hidden_weak (__open)
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weak_alias (__libc_open, open)
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int
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__open_nocancel (const char *file, int oflag, ...)
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{
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  int mode = 0;
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  if (__OPEN_NEEDS_MODE (oflag))
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    {
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      va_list arg;
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      va_start (arg, oflag);
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      mode = va_arg (arg, int);
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      va_end (arg);
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    }
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  return INLINE_SYSCALL (openat, 4, AT_FDCWD, file, oflag, mode);
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}
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