diff options
Diffstat (limited to 'src/malloc_hook.cc')
-rw-r--r-- | src/malloc_hook.cc | 197 |
1 files changed, 12 insertions, 185 deletions
diff --git a/src/malloc_hook.cc b/src/malloc_hook.cc index 5a61362..dc4539c 100644 --- a/src/malloc_hook.cc +++ b/src/malloc_hook.cc @@ -283,7 +283,7 @@ int HookList<T>::Traverse(T* output_array, int n) const { // Explicit instantiation for malloc_hook_test.cc. This ensures all the methods // are instantiated. -template class HookList<MallocHook::NewHook>; +template struct HookList<MallocHook::NewHook>; HookList<MallocHook::NewHook> new_hooks_ = INIT_HOOK_LIST_WITH_VALUE(&InitialNewHook); @@ -698,191 +698,19 @@ extern "C" int MallocHook_GetCallerStackTrace(void** result, int max_depth, #endif } -// On Linux/x86, we override mmap/munmap/mremap/sbrk -// and provide support for calling the related hooks. -// -// 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. - - -#if defined(__linux) && \ - (defined(__i386__) || defined(__x86_64__) || defined(__PPC__)) -#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(). -#if defined(__x86_64__) || defined(__PPC64__) - -static inline void* do_mmap64(void *start, size_t length, - int prot, int flags, - int fd, __off64_t offset) __THROW { - return (void *)syscall(SYS_mmap, start, length, prot, flags, fd, offset); -} - -#elif defined(__i386__) || defined(__PPC__) - -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; - } - - { - // 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, length, prot, flags, fd, (off_t) offset }; - result = (void *)syscall(SYS_mmap, args); - } - out: - return result; -} - -# endif // defined(__x86_64__) - -// 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) +// On systems where we know how, we override mmap/munmap/mremap/sbrk +// to provide support for calling the related hooks (in addition, +// of course, to doing what these functions normally do). -extern "C" int munmap(void* start, size_t length) __THROW { - MallocHook::InvokeMunmapHook(start, length); - int result; - if (!MallocHook::InvokeMunmapReplacement(start, length, &result)) { - result = syscall(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; -} - -// 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; -} - -/*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; -} +#if defined(__linux) +# include "malloc_hook_mmap_linux.h" -/*static*/int MallocHook::UnhookedMUnmap(void *start, size_t length) { - int result; - if (!MallocHook::InvokeMunmapReplacement(start, length, &result)) { - result = sys_munmap(start, length); - } - return result; -} +// This code doesn't even compile on my freebsd 8.1 (x86_64) system, +// so comment it out for now. TODO(csilvers): fix this! +#elif 0 && defined(__FreeBSD__) +# include "malloc_hook_mmap_freebsd.h" -#else // defined(__linux) && - // (defined(__i386__) || defined(__x86_64__) || defined(__PPC__)) +#else /*static*/void* MallocHook::UnhookedMMap(void *start, size_t length, int prot, int flags, int fd, off_t offset) { @@ -902,5 +730,4 @@ extern "C" void* sbrk(ptrdiff_t increment) __THROW { return result; } -#endif // defined(__linux) && - // (defined(__i386__) || defined(__x86_64__) || defined(__PPC__)) +#endif |