diff options
Diffstat (limited to 'contrib/compiler-rt/lib/interception/interception_linux.cc')
| -rw-r--r-- | contrib/compiler-rt/lib/interception/interception_linux.cc | 60 |
1 files changed, 44 insertions, 16 deletions
diff --git a/contrib/compiler-rt/lib/interception/interception_linux.cc b/contrib/compiler-rt/lib/interception/interception_linux.cc index 26bfcd8f6794..4b27102a159c 100644 --- a/contrib/compiler-rt/lib/interception/interception_linux.cc +++ b/contrib/compiler-rt/lib/interception/interception_linux.cc @@ -1,9 +1,8 @@ //===-- interception_linux.cc -----------------------------------*- C++ -*-===// // -// The LLVM Compiler Infrastructure -// -// This file is distributed under the University of Illinois Open Source -// License. See LICENSE.TXT for details. +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception // //===----------------------------------------------------------------------===// // @@ -19,33 +18,62 @@ #include <dlfcn.h> // for dlsym() and dlvsym() +namespace __interception { + #if SANITIZER_NETBSD -#include "sanitizer_common/sanitizer_libc.h" +static int StrCmp(const char *s1, const char *s2) { + while (true) { + if (*s1 != *s2) + return false; + if (*s1 == 0) + return true; + s1++; + s2++; + } +} #endif -namespace __interception { -bool GetRealFunctionAddress(const char *func_name, uptr *func_addr, - uptr real, uptr wrapper) { +static void *GetFuncAddr(const char *name, uptr wrapper_addr) { #if SANITIZER_NETBSD - // XXX: Find a better way to handle renames - if (internal_strcmp(func_name, "sigaction") == 0) func_name = "__sigaction14"; + // FIXME: Find a better way to handle renames + if (StrCmp(name, "sigaction")) + name = "__sigaction14"; #endif - *func_addr = (uptr)dlsym(RTLD_NEXT, func_name); - if (!*func_addr) { + void *addr = dlsym(RTLD_NEXT, name); + if (!addr) { // If the lookup using RTLD_NEXT failed, the sanitizer runtime library is // later in the library search order than the DSO that we are trying to // intercept, which means that we cannot intercept this function. We still // want the address of the real definition, though, so look it up using // RTLD_DEFAULT. - *func_addr = (uptr)dlsym(RTLD_DEFAULT, func_name); + addr = dlsym(RTLD_DEFAULT, name); + + // In case `name' is not loaded, dlsym ends up finding the actual wrapper. + // We don't want to intercept the wrapper and have it point to itself. + if ((uptr)addr == wrapper_addr) + addr = nullptr; } - return real == wrapper; + return addr; +} + +bool InterceptFunction(const char *name, uptr *ptr_to_real, uptr func, + uptr wrapper) { + void *addr = GetFuncAddr(name, wrapper); + *ptr_to_real = (uptr)addr; + return addr && (func == wrapper); } // Android and Solaris do not have dlvsym #if !SANITIZER_ANDROID && !SANITIZER_SOLARIS && !SANITIZER_OPENBSD -void *GetFuncAddrVer(const char *func_name, const char *ver) { - return dlvsym(RTLD_NEXT, func_name, ver); +static void *GetFuncAddr(const char *name, const char *ver) { + return dlvsym(RTLD_NEXT, name, ver); +} + +bool InterceptFunction(const char *name, const char *ver, uptr *ptr_to_real, + uptr func, uptr wrapper) { + void *addr = GetFuncAddr(name, ver); + *ptr_to_real = (uptr)addr; + return addr && (func == wrapper); } #endif // !SANITIZER_ANDROID |