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-rw-r--r--libmudflap/mf-hooks1.c500
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diff --git a/libmudflap/mf-hooks1.c b/libmudflap/mf-hooks1.c
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+/* Mudflap: narrow-pointer bounds-checking by tree rewriting.
+ Copyright (C) 2002, 2003, 2004, 2009 Free Software Foundation, Inc.
+ Contributed by Frank Ch. Eigler <fche@redhat.com>
+ and Graydon Hoare <graydon@redhat.com>
+
+This file is part of GCC.
+
+GCC is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation; either version 3, or (at your option) any later
+version.
+
+GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+for more details.
+
+Under Section 7 of GPL version 3, you are granted additional
+permissions described in the GCC Runtime Library Exception, version
+3.1, as published by the Free Software Foundation.
+
+You should have received a copy of the GNU General Public License and
+a copy of the GCC Runtime Library Exception along with this program;
+see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
+<http://www.gnu.org/licenses/>. */
+
+#include "config.h"
+
+#ifndef HAVE_SOCKLEN_T
+#define socklen_t int
+#endif
+
+
+/* These attempt to coax various unix flavours to declare all our
+ needed tidbits in the system headers. */
+#if !defined(__FreeBSD__) && !defined(__APPLE__)
+#define _POSIX_SOURCE
+#endif /* Some BSDs break <sys/socket.h> if this is defined. */
+#define _GNU_SOURCE
+#define _XOPEN_SOURCE
+#define _BSD_TYPES
+#define __EXTENSIONS__
+#define _ALL_SOURCE
+#define _LARGE_FILE_API
+#define _XOPEN_SOURCE_EXTENDED 1
+
+#include <string.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/time.h>
+#include <sys/types.h>
+#include <unistd.h>
+#include <assert.h>
+#include <errno.h>
+#include <limits.h>
+#include <time.h>
+
+#include "mf-runtime.h"
+#include "mf-impl.h"
+
+#ifdef _MUDFLAP
+#error "Do not compile this file with -fmudflap!"
+#endif
+
+
+/* Memory allocation related hook functions. Some of these are
+ intercepted via linker wrapping or symbol interposition. Others
+ use plain macros in mf-runtime.h. */
+
+
+#if PIC
+
+enum { BS = 4096, NB=10 };
+static char __mf_0fn_bufs[NB][BS];
+static unsigned __mf_0fn_bufs_used[NB];
+
+
+/* A special bootstrap variant. */
+void *
+__mf_0fn_malloc (size_t c)
+{
+ unsigned i;
+
+ for (i=0; i<NB; i++)
+ {
+ if (! __mf_0fn_bufs_used[i] && c < BS)
+ {
+ __mf_0fn_bufs_used[i] = 1;
+ return & __mf_0fn_bufs[i][0];
+ }
+ }
+ return NULL;
+}
+#endif
+
+
+#undef malloc
+WRAPPER(void *, malloc, size_t c)
+{
+ size_t size_with_crumple_zones;
+ DECLARE(void *, malloc, size_t c);
+ void *result;
+ BEGIN_PROTECT (malloc, c);
+
+ size_with_crumple_zones =
+ CLAMPADD(c,CLAMPADD(__mf_opts.crumple_zone,
+ __mf_opts.crumple_zone));
+ BEGIN_MALLOC_PROTECT ();
+ result = (char *) CALL_REAL (malloc, size_with_crumple_zones);
+ END_MALLOC_PROTECT ();
+
+ if (LIKELY(result))
+ {
+ result += __mf_opts.crumple_zone;
+ __mf_register (result, c, __MF_TYPE_HEAP, "malloc region");
+ /* XXX: register __MF_TYPE_NOACCESS for crumple zones. */
+ }
+
+ return result;
+}
+
+
+#ifdef PIC
+/* A special bootstrap variant. */
+void *
+__mf_0fn_calloc (size_t c, size_t n)
+{
+ return __mf_0fn_malloc (c * n);
+}
+#endif
+
+
+#undef calloc
+WRAPPER(void *, calloc, size_t c, size_t n)
+{
+ size_t size_with_crumple_zones;
+ DECLARE(void *, calloc, size_t, size_t);
+ DECLARE(void *, malloc, size_t);
+ DECLARE(void *, memset, void *, int, size_t);
+ char *result;
+ BEGIN_PROTECT (calloc, c, n);
+
+ size_with_crumple_zones =
+ CLAMPADD((c * n), /* XXX: CLAMPMUL */
+ CLAMPADD(__mf_opts.crumple_zone,
+ __mf_opts.crumple_zone));
+ BEGIN_MALLOC_PROTECT ();
+ result = (char *) CALL_REAL (malloc, size_with_crumple_zones);
+ END_MALLOC_PROTECT ();
+
+ if (LIKELY(result))
+ memset (result, 0, size_with_crumple_zones);
+
+ if (LIKELY(result))
+ {
+ result += __mf_opts.crumple_zone;
+ __mf_register (result, c*n /* XXX: clamp */, __MF_TYPE_HEAP_I, "calloc region");
+ /* XXX: register __MF_TYPE_NOACCESS for crumple zones. */
+ }
+
+ return result;
+}
+
+
+#if PIC
+/* A special bootstrap variant. */
+void *
+__mf_0fn_realloc (void *buf, size_t c)
+{
+ return NULL;
+}
+#endif
+
+
+#undef realloc
+WRAPPER(void *, realloc, void *buf, size_t c)
+{
+ DECLARE(void * , realloc, void *, size_t);
+ size_t size_with_crumple_zones;
+ char *base = buf;
+ unsigned saved_wipe_heap;
+ char *result;
+ BEGIN_PROTECT (realloc, buf, c);
+
+ if (LIKELY(buf))
+ base -= __mf_opts.crumple_zone;
+
+ size_with_crumple_zones =
+ CLAMPADD(c, CLAMPADD(__mf_opts.crumple_zone,
+ __mf_opts.crumple_zone));
+ BEGIN_MALLOC_PROTECT ();
+ result = (char *) CALL_REAL (realloc, base, size_with_crumple_zones);
+ END_MALLOC_PROTECT ();
+
+ /* Ensure heap wiping doesn't occur during this peculiar
+ unregister/reregister pair. */
+ LOCKTH ();
+ __mf_set_state (reentrant);
+ saved_wipe_heap = __mf_opts.wipe_heap;
+ __mf_opts.wipe_heap = 0;
+
+ if (LIKELY(buf))
+ __mfu_unregister (buf, 0, __MF_TYPE_HEAP_I);
+ /* NB: underlying region may have been __MF_TYPE_HEAP. */
+
+ if (LIKELY(result))
+ {
+ result += __mf_opts.crumple_zone;
+ __mfu_register (result, c, __MF_TYPE_HEAP_I, "realloc region");
+ /* XXX: register __MF_TYPE_NOACCESS for crumple zones. */
+ }
+
+ /* Restore previous setting. */
+ __mf_opts.wipe_heap = saved_wipe_heap;
+
+ __mf_set_state (active);
+ UNLOCKTH ();
+
+ return result;
+}
+
+
+#if PIC
+/* A special bootstrap variant. */
+void
+__mf_0fn_free (void *buf)
+{
+ return;
+}
+#endif
+
+#undef free
+WRAPPER(void, free, void *buf)
+{
+ /* Use a circular queue to delay some number (__mf_opts.free_queue_length) of free()s. */
+ static void *free_queue [__MF_FREEQ_MAX];
+ static unsigned free_ptr = 0;
+ static int freeq_initialized = 0;
+ DECLARE(void, free, void *);
+
+ BEGIN_PROTECT (free, buf);
+
+ if (UNLIKELY(buf == NULL))
+ return;
+
+#if PIC
+ /* Check whether the given buffer might have come from a
+ __mf_0fn_malloc/calloc call that for whatever reason was not
+ redirected back to __mf_0fn_free. If so, we just ignore the
+ call. */
+ if (UNLIKELY((uintptr_t) buf >= (uintptr_t) __mf_0fn_bufs &&
+ (uintptr_t) buf < ((uintptr_t) __mf_0fn_bufs + sizeof(__mf_0fn_bufs))))
+ {
+ VERBOSE_TRACE ("skipping free of boot (0fn) alloc buffer %p\n", buf);
+ return;
+ }
+#endif
+
+ LOCKTH ();
+ if (UNLIKELY(!freeq_initialized))
+ {
+ memset (free_queue, 0,
+ __MF_FREEQ_MAX * sizeof (void *));
+ freeq_initialized = 1;
+ }
+ UNLOCKTH ();
+
+ __mf_unregister (buf, 0, __MF_TYPE_HEAP_I);
+ /* NB: underlying region may have been __MF_TYPE_HEAP. */
+
+ if (UNLIKELY(__mf_opts.free_queue_length > 0))
+ {
+ char *freeme = NULL;
+ LOCKTH ();
+ if (free_queue [free_ptr] != NULL)
+ {
+ freeme = free_queue [free_ptr];
+ freeme -= __mf_opts.crumple_zone;
+ }
+ free_queue [free_ptr] = buf;
+ free_ptr = (free_ptr == (__mf_opts.free_queue_length-1) ? 0 : free_ptr + 1);
+ UNLOCKTH ();
+ if (freeme)
+ {
+ if (__mf_opts.trace_mf_calls)
+ {
+ VERBOSE_TRACE ("freeing deferred pointer %p (crumple %u)\n",
+ (void *) freeme,
+ __mf_opts.crumple_zone);
+ }
+ BEGIN_MALLOC_PROTECT ();
+ CALL_REAL (free, freeme);
+ END_MALLOC_PROTECT ();
+ }
+ }
+ else
+ {
+ /* back pointer up a bit to the beginning of crumple zone */
+ char *base = (char *)buf;
+ base -= __mf_opts.crumple_zone;
+ if (__mf_opts.trace_mf_calls)
+ {
+ VERBOSE_TRACE ("freeing pointer %p = %p - %u\n",
+ (void *) base,
+ (void *) buf,
+ __mf_opts.crumple_zone);
+ }
+ BEGIN_MALLOC_PROTECT ();
+ CALL_REAL (free, base);
+ END_MALLOC_PROTECT ();
+ }
+}
+
+
+/* We can only wrap mmap if the target supports it. Likewise for munmap.
+ We assume we have both if we have mmap. */
+#ifdef HAVE_MMAP
+
+#if PIC
+/* A special bootstrap variant. */
+void *
+__mf_0fn_mmap (void *start, size_t l, int prot, int f, int fd, off_t off)
+{
+#if defined(__FreeBSD__)
+ if (f == 0x1000 && fd == -1 && prot == 0 && off == 0)
+ return 0;
+#endif /* Ignore red zone allocation request for initial thread's stack. */
+
+ return (void *) -1;
+}
+#endif
+
+
+#undef mmap
+WRAPPER(void *, mmap,
+ void *start, size_t length, int prot,
+ int flags, int fd, off_t offset)
+{
+ DECLARE(void *, mmap, void *, size_t, int,
+ int, int, off_t);
+ void *result;
+ BEGIN_PROTECT (mmap, start, length, prot, flags, fd, offset);
+
+ result = CALL_REAL (mmap, start, length, prot,
+ flags, fd, offset);
+
+ /*
+ VERBOSE_TRACE ("mmap (%08lx, %08lx, ...) => %08lx\n",
+ (uintptr_t) start, (uintptr_t) length,
+ (uintptr_t) result);
+ */
+
+ if (result != (void *)-1)
+ {
+ /* Register each page as a heap object. Why not register it all
+ as a single segment? That's so that a later munmap() call
+ can unmap individual pages. XXX: would __MF_TYPE_GUESS make
+ this more automatic? */
+ size_t ps = getpagesize ();
+ uintptr_t base = (uintptr_t) result;
+ uintptr_t offset;
+
+ for (offset=0; offset<length; offset+=ps)
+ {
+ /* XXX: We could map PROT_NONE to __MF_TYPE_NOACCESS. */
+ /* XXX: Unaccessed HEAP pages are reported as leaks. Is this
+ appropriate for unaccessed mmap pages? */
+ __mf_register ((void *) CLAMPADD (base, offset), ps,
+ __MF_TYPE_HEAP_I, "mmap page");
+ }
+ }
+
+ return result;
+}
+
+
+#if PIC
+/* A special bootstrap variant. */
+int
+__mf_0fn_munmap (void *start, size_t length)
+{
+ return -1;
+}
+#endif
+
+
+#undef munmap
+WRAPPER(int , munmap, void *start, size_t length)
+{
+ DECLARE(int, munmap, void *, size_t);
+ int result;
+ BEGIN_PROTECT (munmap, start, length);
+
+ result = CALL_REAL (munmap, start, length);
+
+ /*
+ VERBOSE_TRACE ("munmap (%08lx, %08lx, ...) => %08lx\n",
+ (uintptr_t) start, (uintptr_t) length,
+ (uintptr_t) result);
+ */
+
+ if (result == 0)
+ {
+ /* Unregister each page as a heap object. */
+ size_t ps = getpagesize ();
+ uintptr_t base = (uintptr_t) start & (~ (ps - 1)); /* page align */
+ uintptr_t offset;
+
+ for (offset=0; offset<length; offset+=ps)
+ __mf_unregister ((void *) CLAMPADD (base, offset), ps, __MF_TYPE_HEAP_I);
+ }
+ return result;
+}
+#endif /* HAVE_MMAP */
+
+
+/* This wrapper is a little different, as it's called indirectly from
+ __mf_fini also to clean up pending allocations. */
+void *
+__mf_wrap_alloca_indirect (size_t c)
+{
+ DECLARE (void *, malloc, size_t);
+ DECLARE (void, free, void *);
+
+ /* This struct, a linked list, tracks alloca'd objects. The newest
+ object is at the head of the list. If we detect that we've
+ popped a few levels of stack, then the listed objects are freed
+ as needed. NB: The tracking struct is allocated with
+ real_malloc; the user data with wrap_malloc.
+ */
+ struct alloca_tracking { void *ptr; void *stack; struct alloca_tracking* next; };
+ static struct alloca_tracking *alloca_history = NULL;
+
+ void *stack = __builtin_frame_address (0);
+ void *result;
+ struct alloca_tracking *track;
+
+ TRACE ("%s\n", __PRETTY_FUNCTION__);
+ VERBOSE_TRACE ("alloca stack level %p\n", (void *) stack);
+
+ /* XXX: thread locking! */
+
+ /* Free any previously alloca'd blocks that belong to deeper-nested functions,
+ which must therefore have exited by now. */
+
+#define DEEPER_THAN < /* XXX: for x86; steal find_stack_direction() from libiberty/alloca.c */
+
+ while (alloca_history &&
+ ((uintptr_t) alloca_history->stack DEEPER_THAN (uintptr_t) stack))
+ {
+ struct alloca_tracking *next = alloca_history->next;
+ __mf_unregister (alloca_history->ptr, 0, __MF_TYPE_HEAP);
+ BEGIN_MALLOC_PROTECT ();
+ CALL_REAL (free, alloca_history->ptr);
+ CALL_REAL (free, alloca_history);
+ END_MALLOC_PROTECT ();
+ alloca_history = next;
+ }
+
+ /* Allocate new block. */
+ result = NULL;
+ if (LIKELY (c > 0)) /* alloca(0) causes no allocation. */
+ {
+ BEGIN_MALLOC_PROTECT ();
+ track = (struct alloca_tracking *) CALL_REAL (malloc,
+ sizeof (struct alloca_tracking));
+ END_MALLOC_PROTECT ();
+ if (LIKELY (track != NULL))
+ {
+ BEGIN_MALLOC_PROTECT ();
+ result = CALL_REAL (malloc, c);
+ END_MALLOC_PROTECT ();
+ if (UNLIKELY (result == NULL))
+ {
+ BEGIN_MALLOC_PROTECT ();
+ CALL_REAL (free, track);
+ END_MALLOC_PROTECT ();
+ /* Too bad. XXX: What about errno? */
+ }
+ else
+ {
+ __mf_register (result, c, __MF_TYPE_HEAP, "alloca region");
+ track->ptr = result;
+ track->stack = stack;
+ track->next = alloca_history;
+ alloca_history = track;
+ }
+ }
+ }
+
+ return result;
+}
+
+
+#undef alloca
+WRAPPER(void *, alloca, size_t c)
+{
+ return __mf_wrap_alloca_indirect (c);
+}
+
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