68 lines
2.3 KiB
C
68 lines
2.3 KiB
C
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/*
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* Copyright (C) 2012 The Android Open Source Project
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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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* * 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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* * Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in
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* the documentation and/or other materials provided with the
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* distribution.
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*
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
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* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
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* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
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* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
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* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
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* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
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* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
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* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
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* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*/
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#include <string.h>
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#include <stdlib.h>
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#include <private/logd.h>
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/*
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* Runtime implementation of __strlen_chk.
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*
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* See
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* http://gcc.gnu.org/onlinedocs/gcc/Object-Size-Checking.html
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* http://gcc.gnu.org/ml/gcc-patches/2004-09/msg02055.html
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* for details.
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*
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* This strlen check is called if _FORTIFY_SOURCE is defined and
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* greater than 0.
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*
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* This test is designed to detect code such as:
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*
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* int main() {
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* char buf[10];
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* memcpy(buf, "1234567890", sizeof(buf));
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* size_t len = strlen(buf); // segfault here with _FORTIFY_SOURCE
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* printf("%d\n", len);
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* return 0;
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* }
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*
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* or anytime strlen reads beyond an object boundary.
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*/
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size_t __strlen_chk(const char *s, size_t s_len)
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{
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size_t ret = strlen(s);
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if (__builtin_expect(ret >= s_len, 0)) {
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__libc_android_log_print(ANDROID_LOG_FATAL, "libc",
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"*** strlen read overflow detected ***\n");
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abort();
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}
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return ret;
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}
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