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	The BZ 32653 fix (12a497c716) kept the stack pointer zeroing from make_main_stack_executable on _dl_make_stack_executable. However, previously the 'stack_endp' pointed to temporary variable created before the call of _dl_map_object_from_fd; while now we use the __libc_stack_end directly. Since pthread_getattr_np relies on correct __libc_stack_end, if _dl_make_stack_executable is called (for instance, when glibc.rtld.execstack=2 is set) __libc_stack_end will be set to zero, and the call will always fail. The __libc_stack_end zero was used a mitigation hardening, but since52a01100adit is used solely on pthread_getattr_np code. So there is no point in zeroing anymore. Checked on x86_64-linux-gnu and i686-linux-gnu. Reviewed-by: Sam James <sam@gentoo.org>
		
			
				
	
	
		
			40 lines
		
	
	
		
			1.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			40 lines
		
	
	
		
			1.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/* Check if pthread_getattr_np works within modules with non-exectuble
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   stacks (BZ 32897).
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   Copyright (C) 2025 Free Software Foundation, Inc.
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   This file is part of the GNU C Library.
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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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   <https://www.gnu.org/licenses/>.  */
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#include <pthread.h>
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bool init_result;
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void
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__attribute__ ((constructor))
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init (void)
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{
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  pthread_t me = pthread_self ();
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  pthread_attr_t attr;
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  init_result = pthread_getattr_np (me, &attr) == 0;
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}
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int
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mod_func (void)
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{
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  pthread_t me = pthread_self ();
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  pthread_attr_t attr;
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  return pthread_getattr_np (me, &attr);
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}
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