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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.
		
			
				
	
	
		
			51 lines
		
	
	
		
			1.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			51 lines
		
	
	
		
			1.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* Copyright (C) 1991-2015 Free Software Foundation, Inc.
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|    This file is part of the GNU C Library.
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| 
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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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| 
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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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| 
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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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| 
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| #include <fcntl.h>
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| #include <stdarg.h>
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| #include <sysdep-cancel.h>
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| 
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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_open64 (const char *file, int oflag, ...)
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| {
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|   int mode = 0;
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| 
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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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| 
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|   if (SINGLE_THREAD_P)
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|     return __libc_open (file, oflag | O_LARGEFILE, mode);
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| 
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|   int oldtype = LIBC_CANCEL_ASYNC ();
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| 
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|   int result = __libc_open (file, oflag | O_LARGEFILE, mode);
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| 
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|   LIBC_CANCEL_RESET (oldtype);
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| 
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|   return result;
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| }
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| weak_alias (__libc_open64, __open64)
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| libc_hidden_weak (__open64)
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| weak_alias (__libc_open64, open64)
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