96 lines
		
	
	
		
			2.6 KiB
		
	
	
	
		
			C
		
	
	
	
			
		
		
	
	
			96 lines
		
	
	
		
			2.6 KiB
		
	
	
	
		
			C
		
	
	
	
| /*
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|  * Copyright (c) 2014-2016 Dmitry V. Levin <ldv@altlinux.org>
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|  * All rights reserved.
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|  *
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|  * Redistribution and use in source and binary forms, with or without
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|  * modification, are permitted provided that the following conditions
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|  * are met:
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|  * 1. Redistributions of source code must retain the above copyright
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|  *    notice, this list of conditions and the following disclaimer.
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|  * 2. Redistributions in binary form must reproduce the above copyright
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|  *    notice, this list of conditions and the following disclaimer in the
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|  *    documentation and/or other materials provided with the distribution.
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|  * 3. The name of the author may not be used to endorse or promote products
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|  *    derived from this software without specific prior written permission.
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|  *
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|  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
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|  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
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|  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
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|  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
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|  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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|  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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|  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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|  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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|  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
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|  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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|  */
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| 
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| #include "tests.h"
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| #include <errno.h>
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| #include <fcntl.h>
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| #include <stdlib.h>
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| #include <unistd.h>
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| 
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| int
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| read_int_from_file(const char *const fname, int *const pvalue)
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| {
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| 	const int fd = open(fname, O_RDONLY);
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| 	if (fd < 0)
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| 		return -1;
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| 
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| 	long lval;
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| 	char buf[sizeof(lval) * 3];
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| 	int n = read(fd, buf, sizeof(buf) - 1);
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| 	int saved_errno = errno;
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| 	close(fd);
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| 
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| 	if (n < 0) {
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| 		errno = saved_errno;
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| 		return -1;
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| 	}
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| 
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| 	buf[n] = '\0';
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| 	char *endptr = 0;
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| 	errno = 0;
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| 	lval = strtol(buf, &endptr, 10);
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| 	if (!endptr || (*endptr && '\n' != *endptr)
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| #if INT_MAX < LONG_MAX
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| 	    || lval > INT_MAX || lval < INT_MIN
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| #endif
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| 	    || ERANGE == errno) {
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| 		if (!errno)
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| 			errno = EINVAL;
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| 		return -1;
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| 	}
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| 
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| 	*pvalue = (int) lval;
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| 	return 0;
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| }
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| 
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| static void
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| check_overflow_id(const int id, const char *overflowid)
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| {
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| 	int n;
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| 
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| 	if (read_int_from_file(overflowid, &n)) {
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| 		if (ENOENT == errno)
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| 			return;
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| 		perror_msg_and_fail("read_int_from_file: %s", overflowid);
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| 	}
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| 
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| 	if (id == n)
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| 		error_msg_and_skip("%d matches %s", id, overflowid);
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| }
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| 
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| void
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| check_overflowuid(const int uid)
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| {
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| 	check_overflow_id(uid, "/proc/sys/kernel/overflowuid");
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| }
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| 
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| void
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| check_overflowgid(const int gid)
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| {
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| 	check_overflow_id(gid, "/proc/sys/kernel/overflowgid");
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| }
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