| // -*- Mode: C++; c-basic-offset: 2; indent-tabs-mode: nil -*- |
| // Copyright (c) 2005, Google Inc. |
| // All rights reserved. |
| // |
| // Redistribution and use in source and binary forms, with or without |
| // modification, are permitted provided that the following conditions are |
| // met: |
| // |
| // * Redistributions of source code must retain the above copyright |
| // notice, this list of conditions and the following disclaimer. |
| // * Redistributions in binary form must reproduce the above |
| // copyright notice, this list of conditions and the following disclaimer |
| // in the documentation and/or other materials provided with the |
| // distribution. |
| // * Neither the name of Google Inc. nor the names of its |
| // contributors may be used to endorse or promote products derived from |
| // this software without specific prior written permission. |
| // |
| // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| |
| // --- |
| // Author: Sanjay Ghemawat <opensource@google.com> |
| |
| // We define mmap() and mmap64(), which somewhat reimplements libc's mmap |
| // syscall stubs. Unfortunately libc only exports the stubs via weak symbols |
| // (which we're overriding with our mmap64() and mmap() wrappers) so we can't |
| // just call through to them. |
| |
| #ifndef __linux |
| # error Should only be including malloc_hook_mmap_linux.h on linux systems. |
| #endif |
| |
| #include <unistd.h> |
| #include <syscall.h> |
| #include <sys/mman.h> |
| #include <errno.h> |
| #include "base/linux_syscall_support.h" |
| |
| // The x86-32 case and the x86-64 case differ: |
| // 32b has a mmap2() syscall, 64b does not. |
| // 64b and 32b have different calling conventions for mmap(). |
| |
| // I test for 64-bit first so I don't have to do things like |
| // '#if (defined(__mips__) && !defined(__MIPS64__))' as a mips32 check. |
| #if defined(__x86_64__) || defined(__PPC64__) || defined(__aarch64__) || (defined(_MIPS_SIM) && _MIPS_SIM == _ABI64) |
| |
| static inline void* do_mmap64(void *start, size_t length, |
| int prot, int flags, |
| int fd, __off64_t offset) __THROW { |
| return sys_mmap(start, length, prot, flags, fd, offset); |
| } |
| |
| #define MALLOC_HOOK_HAVE_DO_MMAP64 1 |
| |
| #elif defined(__i386__) || defined(__PPC__) || defined(__mips__) || \ |
| defined(__arm__) |
| |
| static inline void* do_mmap64(void *start, size_t length, |
| int prot, int flags, |
| int fd, __off64_t offset) __THROW { |
| void *result; |
| |
| // Try mmap2() unless it's not supported |
| static bool have_mmap2 = true; |
| if (have_mmap2) { |
| static int pagesize = 0; |
| if (!pagesize) pagesize = getpagesize(); |
| |
| // Check that the offset is page aligned |
| if (offset & (pagesize - 1)) { |
| result = MAP_FAILED; |
| errno = EINVAL; |
| goto out; |
| } |
| |
| result = (void *)syscall(SYS_mmap2, |
| start, length, prot, flags, fd, |
| (off_t) (offset / pagesize)); |
| if (result != MAP_FAILED || errno != ENOSYS) goto out; |
| |
| // We don't have mmap2() after all - don't bother trying it in future |
| have_mmap2 = false; |
| } |
| |
| if (((off_t)offset) != offset) { |
| // If we're trying to map a 64-bit offset, fail now since we don't |
| // have 64-bit mmap() support. |
| result = MAP_FAILED; |
| errno = EINVAL; |
| goto out; |
| } |
| |
| #ifdef __NR_mmap |
| { |
| // Fall back to old 32-bit offset mmap() call |
| // Old syscall interface cannot handle six args, so pass in an array |
| int32 args[6] = { (int32) start, (int32) length, prot, flags, fd, |
| (int32)(off_t) offset }; |
| result = (void *)syscall(SYS_mmap, args); |
| } |
| #else |
| // Some Linux ports like ARM EABI Linux has no mmap, just mmap2. |
| result = MAP_FAILED; |
| #endif |
| |
| out: |
| return result; |
| } |
| |
| #define MALLOC_HOOK_HAVE_DO_MMAP64 1 |
| |
| #endif // #if defined(__x86_64__) |
| |
| |
| #ifdef MALLOC_HOOK_HAVE_DO_MMAP64 |
| |
| // We use do_mmap64 abstraction to put MallocHook::InvokeMmapHook |
| // calls right into mmap and mmap64, so that the stack frames in the caller's |
| // stack are at the same offsets for all the calls of memory allocating |
| // functions. |
| |
| // Put all callers of MallocHook::Invoke* in this module into |
| // malloc_hook section, |
| // so that MallocHook::GetCallerStackTrace can function accurately: |
| |
| // Make sure mmap doesn't get #define'd away by <sys/mman.h> |
| # undef mmap |
| |
| extern "C" { |
| void* mmap64(void *start, size_t length, int prot, int flags, |
| int fd, __off64_t offset ) __THROW |
| ATTRIBUTE_SECTION(malloc_hook); |
| void* mmap(void *start, size_t length,int prot, int flags, |
| int fd, off_t offset) __THROW |
| ATTRIBUTE_SECTION(malloc_hook); |
| int munmap(void* start, size_t length) __THROW |
| ATTRIBUTE_SECTION(malloc_hook); |
| void* mremap(void* old_addr, size_t old_size, size_t new_size, |
| int flags, ...) __THROW |
| ATTRIBUTE_SECTION(malloc_hook); |
| void* sbrk(ptrdiff_t increment) __THROW |
| ATTRIBUTE_SECTION(malloc_hook); |
| } |
| |
| extern "C" void* mmap64(void *start, size_t length, int prot, int flags, |
| int fd, __off64_t offset) __THROW { |
| MallocHook::InvokePreMmapHook(start, length, prot, flags, fd, offset); |
| void *result; |
| if (!MallocHook::InvokeMmapReplacement( |
| start, length, prot, flags, fd, offset, &result)) { |
| result = do_mmap64(start, length, prot, flags, fd, offset); |
| } |
| MallocHook::InvokeMmapHook(result, start, length, prot, flags, fd, offset); |
| return result; |
| } |
| |
| # if !defined(__USE_FILE_OFFSET64) || !defined(__REDIRECT_NTH) |
| |
| extern "C" void* mmap(void *start, size_t length, int prot, int flags, |
| int fd, off_t offset) __THROW { |
| MallocHook::InvokePreMmapHook(start, length, prot, flags, fd, offset); |
| void *result; |
| if (!MallocHook::InvokeMmapReplacement( |
| start, length, prot, flags, fd, offset, &result)) { |
| result = do_mmap64(start, length, prot, flags, fd, |
| static_cast<size_t>(offset)); // avoid sign extension |
| } |
| MallocHook::InvokeMmapHook(result, start, length, prot, flags, fd, offset); |
| return result; |
| } |
| |
| # endif // !defined(__USE_FILE_OFFSET64) || !defined(__REDIRECT_NTH) |
| |
| extern "C" int munmap(void* start, size_t length) __THROW { |
| MallocHook::InvokeMunmapHook(start, length); |
| int result; |
| if (!MallocHook::InvokeMunmapReplacement(start, length, &result)) { |
| result = sys_munmap(start, length); |
| } |
| return result; |
| } |
| |
| extern "C" void* mremap(void* old_addr, size_t old_size, size_t new_size, |
| int flags, ...) __THROW { |
| va_list ap; |
| va_start(ap, flags); |
| void *new_address = va_arg(ap, void *); |
| va_end(ap); |
| void* result = sys_mremap(old_addr, old_size, new_size, flags, new_address); |
| MallocHook::InvokeMremapHook(result, old_addr, old_size, new_size, flags, |
| new_address); |
| return result; |
| } |
| |
| #ifndef __UCLIBC__ |
| // libc's version: |
| extern "C" void* __sbrk(ptrdiff_t increment); |
| |
| extern "C" void* sbrk(ptrdiff_t increment) __THROW { |
| MallocHook::InvokePreSbrkHook(increment); |
| void *result = __sbrk(increment); |
| MallocHook::InvokeSbrkHook(result, increment); |
| return result; |
| } |
| |
| #endif |
| |
| /*static*/void* MallocHook::UnhookedMMap(void *start, size_t length, int prot, |
| int flags, int fd, off_t offset) { |
| void* result; |
| if (!MallocHook::InvokeMmapReplacement( |
| start, length, prot, flags, fd, offset, &result)) { |
| result = do_mmap64(start, length, prot, flags, fd, offset); |
| } |
| return result; |
| } |
| |
| /*static*/int MallocHook::UnhookedMUnmap(void *start, size_t length) { |
| int result; |
| if (!MallocHook::InvokeMunmapReplacement(start, length, &result)) { |
| result = syscall(SYS_munmap, start, length); |
| } |
| return result; |
| } |
| |
| #undef MALLOC_HOOK_HAVE_DO_MMAP64 |
| |
| #endif // #ifdef MALLOC_HOOK_HAVE_DO_MMAP64 |