1 /* 2 * Copyright (C) 2019 The Android Open Source Project 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * * Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * * Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in 12 * the documentation and/or other materials provided with the 13 * distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 18 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 19 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 22 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 25 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 // This shared object test library is dlopen'ed by the main test executable. 30 31 // Export a large TLS variable from a solib for testing dladdr and dlsym. The 32 // TLS symbol's value will appear to overlap almost everything else in the 33 // shared object, but dladdr must not return it. 34 __thread char large_tls_var[4 * 1024 * 1024]; 35 36 extern "C" char* get_large_tls_var_addr() { 37 return large_tls_var; 38 } 39 40 // For testing dladdr, return an address that's part of the solib's .bss 41 // section, but does not have an entry in the dynsym table and whose 42 // solib-relative address appears to overlap with the large TLS variable. 43 extern "C" void* get_local_addr() { 44 static char dummy[1024]; 45 return &dummy[512]; 46 } 47 48 // This variable comes from libtest_elftls_shared_var.so, which is part of 49 // static TLS. Verify that a GD-model access can access the variable. 50 // 51 // Accessing the static TLS variable from an solib prevents the static linker 52 // from relaxing the GD access to IE and lets us test that __tls_get_addr and 53 // the tlsdesc resolver handle a static TLS variable. 54 extern "C" __thread int elftls_shared_var; 55 56 extern "C" int bump_shared_var() { 57 return ++elftls_shared_var; 58 } 59 60 // The static linker denotes the current module by omitting the symbol from 61 // the DTPMOD/TLSDESC relocations. 62 static __thread int local_var_1 = 15; 63 static __thread int local_var_2 = 25; 64 65 extern "C" int bump_local_vars() { 66 return ++local_var_1 + ++local_var_2; 67 } 68 69 __attribute__((weak)) extern "C" __thread int missing_weak_dyn_tls; 70 71 extern "C" int* missing_weak_dyn_tls_addr() { 72 return &missing_weak_dyn_tls; 73 } 74