clear_cache_test.c revision 7e8904f4b2b6b084ea2b4203d62554b42c068296
1b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbar//===-- clear_cache_test.c - Test clear_cache -----------------------------===// 2b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbar// 3b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbar// The LLVM Compiler Infrastructure 4b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbar// 59ad441ffec97db647fee3725b3424284fb913e14Howard Hinnant// This file is dual licensed under the MIT and the University of Illinois Open 69ad441ffec97db647fee3725b3424284fb913e14Howard Hinnant// Source Licenses. See LICENSE.TXT for details. 7b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbar// 8b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbar//===----------------------------------------------------------------------===// 9b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbar 10b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbar 11b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbar#include <stdio.h> 12b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbar#include <string.h> 13b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbar#include <stdint.h> 147e8904f4b2b6b084ea2b4203d62554b42c068296Anton Korobeynikov#if defined(_WIN32) 157e8904f4b2b6b084ea2b4203d62554b42c068296Anton Korobeynikov#include <windows.h> 167e8904f4b2b6b084ea2b4203d62554b42c068296Anton Korobeynikovvoid __clear_cache(void* start, void* end) 177e8904f4b2b6b084ea2b4203d62554b42c068296Anton Korobeynikov{ 187e8904f4b2b6b084ea2b4203d62554b42c068296Anton Korobeynikov if (!FlushInstructionCache(GetCurrentProcess(), start, end-start)) 197e8904f4b2b6b084ea2b4203d62554b42c068296Anton Korobeynikov exit(1); 207e8904f4b2b6b084ea2b4203d62554b42c068296Anton Korobeynikov} 217e8904f4b2b6b084ea2b4203d62554b42c068296Anton Korobeynikov#else 22b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbar#include <sys/mman.h> 237e8904f4b2b6b084ea2b4203d62554b42c068296Anton Korobeynikovextern void __clear_cache(void* start, void* end); 247e8904f4b2b6b084ea2b4203d62554b42c068296Anton Korobeynikov#endif 25b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbar 26b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbar 27b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbar 28b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbar 29b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbartypedef int (*pfunc)(void); 30b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbar 31b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbarint func1() 32b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbar{ 33b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbar return 1; 34b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbar} 35b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbar 36b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbarint func2() 37b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbar{ 38b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbar return 2; 39b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbar} 40b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbar 41b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbar 42b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbar 43b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbarunsigned char execution_buffer[128]; 44b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbar 45b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbarint main() 46b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbar{ 47b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbar // make executable the page containing execution_buffer 48b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbar char* start = (char*)((uintptr_t)execution_buffer & (-4095)); 49b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbar char* end = (char*)((uintptr_t)(&execution_buffer[128+4096]) & (-4095)); 507e8904f4b2b6b084ea2b4203d62554b42c068296Anton Korobeynikov#if defined(_WIN32) 517e8904f4b2b6b084ea2b4203d62554b42c068296Anton Korobeynikov DWORD dummy_oldProt; 527e8904f4b2b6b084ea2b4203d62554b42c068296Anton Korobeynikov MEMORY_BASIC_INFORMATION b; 537e8904f4b2b6b084ea2b4203d62554b42c068296Anton Korobeynikov if (!VirtualQuery(start, &b, sizeof(b))) 547e8904f4b2b6b084ea2b4203d62554b42c068296Anton Korobeynikov return 1; 557e8904f4b2b6b084ea2b4203d62554b42c068296Anton Korobeynikov if (!VirtualProtect(b.BaseAddress, b.RegionSize, PAGE_EXECUTE_READWRITE, &b.Protect)) 567e8904f4b2b6b084ea2b4203d62554b42c068296Anton Korobeynikov#else 577e8904f4b2b6b084ea2b4203d62554b42c068296Anton Korobeynikov if (mprotect(start, end-start, PROT_READ|PROT_WRITE|PROT_EXEC) != 0) 587e8904f4b2b6b084ea2b4203d62554b42c068296Anton Korobeynikov#endif 59b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbar return 1; 60b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbar 61b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbar // verify you can copy and execute a function 62a07fa29cead05031869b7488f4e845584e57b628Shantonu Sen memcpy(execution_buffer, (void *)(uintptr_t)&func1, 128); 63b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbar __clear_cache(execution_buffer, &execution_buffer[128]); 64a07fa29cead05031869b7488f4e845584e57b628Shantonu Sen pfunc f1 = (pfunc)(uintptr_t)execution_buffer; 657e8904f4b2b6b084ea2b4203d62554b42c068296Anton Korobeynikov if ((*f1)() != 1) 66b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbar return 1; 67b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbar 68b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbar // verify you can overwrite a function with another 69a07fa29cead05031869b7488f4e845584e57b628Shantonu Sen memcpy(execution_buffer, (void *)(uintptr_t)&func2, 128); 70b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbar __clear_cache(execution_buffer, &execution_buffer[128]); 71a07fa29cead05031869b7488f4e845584e57b628Shantonu Sen pfunc f2 = (pfunc)(uintptr_t)execution_buffer; 727e8904f4b2b6b084ea2b4203d62554b42c068296Anton Korobeynikov if ((*f2)() != 2) 73b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbar return 1; 74b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbar 75b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbar return 0; 76b3a6901e66f55b35aa9e01bcb24134e6a65ea004Daniel Dunbar} 77