forked from OSchip/llvm-project
60 lines
1.5 KiB
C
60 lines
1.5 KiB
C
//===-- clear_cache_test.c - Test clear_cache -----------------------------===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is dual licensed under the MIT and the University of Illinois Open
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// Source Licenses. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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#include <stdio.h>
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#include <string.h>
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#include <stdint.h>
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#include <sys/mman.h>
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extern void __clear_cache(void* start, void* end);
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typedef int (*pfunc)(void);
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int func1()
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{
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return 1;
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}
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int func2()
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{
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return 2;
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}
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unsigned char execution_buffer[128];
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int main()
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{
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// make executable the page containing execution_buffer
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char* start = (char*)((uintptr_t)execution_buffer & (-4095));
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char* end = (char*)((uintptr_t)(&execution_buffer[128+4096]) & (-4095));
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if ( mprotect(start, end-start, PROT_READ|PROT_WRITE|PROT_EXEC) != 0 )
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return 1;
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// verify you can copy and execute a function
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memcpy(execution_buffer, (void *)(uintptr_t)&func1, 128);
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__clear_cache(execution_buffer, &execution_buffer[128]);
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pfunc f1 = (pfunc)(uintptr_t)execution_buffer;
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if ( (*f1)() != 1 )
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return 1;
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// verify you can overwrite a function with another
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memcpy(execution_buffer, (void *)(uintptr_t)&func2, 128);
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__clear_cache(execution_buffer, &execution_buffer[128]);
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pfunc f2 = (pfunc)(uintptr_t)execution_buffer;
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if ( (*f2)() != 2 )
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return 1;
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return 0;
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}
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