/* Malloc implementation for multiple threads without lock contention.
- Copyright (C) 2001-2013 Free Software Foundation, Inc.
+ Copyright (C) 2001-2019 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Wolfram Gloger <wg@malloc.de>, 2001.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; see the file COPYING.LIB. If
- not, see <http://www.gnu.org/licenses/>. */
+ not, see <https://www.gnu.org/licenses/>. */
/* What to do if the standard debugging hooks are in place and a
corrupt pointer is detected: do nothing (0), print an error message
/* Hooks for debugging versions. The initial hooks just call the
initialization routine, then do the normal work. */
-static void*
-malloc_hook_ini(size_t sz, const void *caller)
+static void *
+malloc_hook_ini (size_t sz, const void *caller)
{
__malloc_hook = NULL;
- ptmalloc_init();
- return __libc_malloc(sz);
+ ptmalloc_init ();
+ return __libc_malloc (sz);
}
-static void*
-realloc_hook_ini(void* ptr, size_t sz, const void *caller)
+static void *
+realloc_hook_ini (void *ptr, size_t sz, const void *caller)
{
__malloc_hook = NULL;
__realloc_hook = NULL;
- ptmalloc_init();
- return __libc_realloc(ptr, sz);
+ ptmalloc_init ();
+ return __libc_realloc (ptr, sz);
}
-static void*
-memalign_hook_ini(size_t alignment, size_t sz, const void *caller)
+static void *
+memalign_hook_ini (size_t alignment, size_t sz, const void *caller)
{
__memalign_hook = NULL;
- ptmalloc_init();
- return __libc_memalign(alignment, sz);
+ ptmalloc_init ();
+ return __libc_memalign (alignment, sz);
}
/* Whether we are using malloc checking. */
static int using_malloc_checking;
-/* A flag that is set by malloc_set_state, to signal that malloc checking
- must not be enabled on the request from the user (via the MALLOC_CHECK_
- environment variable). It is reset by __malloc_check_init to tell
- malloc_set_state that the user has requested malloc checking.
-
- The purpose of this flag is to make sure that malloc checking is not
- enabled when the heap to be restored was constructed without malloc
- checking, and thus does not contain the required magic bytes.
- Otherwise the heap would be corrupted by calls to free and realloc. If
- it turns out that the heap was created with malloc checking and the
- user has requested it malloc_set_state just calls __malloc_check_init
- again to enable it. On the other hand, reusing such a heap without
- further malloc checking is safe. */
-static int disallow_malloc_check;
-
/* Activate a standard set of debugging hooks. */
void
-__malloc_check_init()
+__malloc_check_init (void)
{
- if (disallow_malloc_check) {
- disallow_malloc_check = 0;
- return;
- }
using_malloc_checking = 1;
__malloc_hook = malloc_check;
__free_hook = free_check;
overruns. The goal here is to avoid obscure crashes due to invalid
usage, unlike in the MALLOC_DEBUG code. */
-#define MAGICBYTE(p) ( ( ((size_t)p >> 3) ^ ((size_t)p >> 11)) & 0xFF )
+static unsigned char
+magicbyte (const void *p)
+{
+ unsigned char magic;
+
+ magic = (((uintptr_t) p >> 3) ^ ((uintptr_t) p >> 11)) & 0xFF;
+ /* Do not return 1. See the comment in mem2mem_check(). */
+ if (magic == 1)
+ ++magic;
+ return magic;
+}
+
-/* Visualize the chunk as being partitioned into blocks of 256 bytes from the
- highest address of the chunk, downwards. The beginning of each block tells
- us the size of the previous block, up to the actual size of the requested
+/* Visualize the chunk as being partitioned into blocks of 255 bytes from the
+ highest address of the chunk, downwards. The end of each block tells
+ us the size of that block, up to the actual size of the requested
memory. Our magic byte is right at the end of the requested size, so we
must reach it with this iteration, otherwise we have witnessed a memory
corruption. */
static size_t
-malloc_check_get_size(mchunkptr p)
+malloc_check_get_size (mchunkptr p)
{
size_t size;
unsigned char c;
- unsigned char magic = MAGICBYTE(p);
+ unsigned char magic = magicbyte (p);
- assert(using_malloc_checking == 1);
+ assert (using_malloc_checking == 1);
- for (size = chunksize(p) - 1 + (chunk_is_mmapped(p) ? 0 : SIZE_SZ);
- (c = ((unsigned char*)p)[size]) != magic;
- size -= c) {
- if(c<=0 || size<(c+2*SIZE_SZ)) {
- malloc_printerr(check_action, "malloc_check_get_size: memory corruption",
- chunk2mem(p));
- return 0;
+ for (size = chunksize (p) - 1 + (chunk_is_mmapped (p) ? 0 : SIZE_SZ);
+ (c = ((unsigned char *) p)[size]) != magic;
+ size -= c)
+ {
+ if (c <= 0 || size < (c + 2 * SIZE_SZ))
+ malloc_printerr ("malloc_check_get_size: memory corruption");
}
- }
/* chunk2mem size. */
- return size - 2*SIZE_SZ;
+ return size - 2 * SIZE_SZ;
}
/* Instrument a chunk with overrun detector byte(s) and convert it
- into a user pointer with requested size sz. */
+ into a user pointer with requested size req_sz. */
-static void*
-internal_function
-mem2mem_check(void *ptr, size_t sz)
+static void *
+mem2mem_check (void *ptr, size_t req_sz)
{
mchunkptr p;
- unsigned char* m_ptr = ptr;
- size_t i;
+ unsigned char *m_ptr = ptr;
+ size_t max_sz, block_sz, i;
+ unsigned char magic;
if (!ptr)
return ptr;
- p = mem2chunk(ptr);
- for(i = chunksize(p) - (chunk_is_mmapped(p) ? 2*SIZE_SZ+1 : SIZE_SZ+1);
- i > sz;
- i -= 0xFF) {
- if(i-sz < 0x100) {
- m_ptr[i] = (unsigned char)(i-sz);
- break;
+
+ p = mem2chunk (ptr);
+ magic = magicbyte (p);
+ max_sz = chunksize (p) - 2 * SIZE_SZ;
+ if (!chunk_is_mmapped (p))
+ max_sz += SIZE_SZ;
+ for (i = max_sz - 1; i > req_sz; i -= block_sz)
+ {
+ block_sz = MIN (i - req_sz, 0xff);
+ /* Don't allow the magic byte to appear in the chain of length bytes.
+ For the following to work, magicbyte cannot return 0x01. */
+ if (block_sz == magic)
+ --block_sz;
+
+ m_ptr[i] = block_sz;
}
- m_ptr[i] = 0xFF;
- }
- m_ptr[sz] = MAGICBYTE(p);
- return (void*)m_ptr;
+ m_ptr[req_sz] = magic;
+ return (void *) m_ptr;
}
/* Convert a pointer to be free()d or realloc()ed to a valid chunk
pointer. If the provided pointer is not valid, return NULL. */
static mchunkptr
-internal_function
-mem2chunk_check(void* mem, unsigned char **magic_p)
+mem2chunk_check (void *mem, unsigned char **magic_p)
{
mchunkptr p;
INTERNAL_SIZE_T sz, c;
unsigned char magic;
- if(!aligned_OK(mem)) return NULL;
- p = mem2chunk(mem);
- if (!chunk_is_mmapped(p)) {
- /* Must be a chunk in conventional heap memory. */
- int contig = contiguous(&main_arena);
- sz = chunksize(p);
- if((contig &&
- ((char*)p<mp_.sbrk_base ||
- ((char*)p + sz)>=(mp_.sbrk_base+main_arena.system_mem) )) ||
- sz<MINSIZE || sz&MALLOC_ALIGN_MASK || !inuse(p) ||
- ( !prev_inuse(p) && (p->prev_size&MALLOC_ALIGN_MASK ||
- (contig && (char*)prev_chunk(p)<mp_.sbrk_base) ||
- next_chunk(prev_chunk(p))!=p) ))
- return NULL;
- magic = MAGICBYTE(p);
- for(sz += SIZE_SZ-1; (c = ((unsigned char*)p)[sz]) != magic; sz -= c) {
- if(c<=0 || sz<(c+2*SIZE_SZ)) return NULL;
+ if (!aligned_OK (mem))
+ return NULL;
+
+ p = mem2chunk (mem);
+ sz = chunksize (p);
+ magic = magicbyte (p);
+ if (!chunk_is_mmapped (p))
+ {
+ /* Must be a chunk in conventional heap memory. */
+ int contig = contiguous (&main_arena);
+ if ((contig &&
+ ((char *) p < mp_.sbrk_base ||
+ ((char *) p + sz) >= (mp_.sbrk_base + main_arena.system_mem))) ||
+ sz < MINSIZE || sz & MALLOC_ALIGN_MASK || !inuse (p) ||
+ (!prev_inuse (p) && ((prev_size (p) & MALLOC_ALIGN_MASK) != 0 ||
+ (contig && (char *) prev_chunk (p) < mp_.sbrk_base) ||
+ next_chunk (prev_chunk (p)) != p)))
+ return NULL;
+
+ for (sz += SIZE_SZ - 1; (c = ((unsigned char *) p)[sz]) != magic; sz -= c)
+ {
+ if (c == 0 || sz < (c + 2 * SIZE_SZ))
+ return NULL;
+ }
}
- } else {
- unsigned long offset, page_mask = GLRO(dl_pagesize)-1;
-
- /* mmap()ed chunks have MALLOC_ALIGNMENT or higher power-of-two
- alignment relative to the beginning of a page. Check this
- first. */
- offset = (unsigned long)mem & page_mask;
- if((offset!=MALLOC_ALIGNMENT && offset!=0 && offset!=0x10 &&
- offset!=0x20 && offset!=0x40 && offset!=0x80 && offset!=0x100 &&
- offset!=0x200 && offset!=0x400 && offset!=0x800 && offset!=0x1000 &&
- offset<0x2000) ||
- !chunk_is_mmapped(p) || (p->size & PREV_INUSE) ||
- ( (((unsigned long)p - p->prev_size) & page_mask) != 0 ) ||
- ( (sz = chunksize(p)), ((p->prev_size + sz) & page_mask) != 0 ) )
- return NULL;
- magic = MAGICBYTE(p);
- for(sz -= 1; (c = ((unsigned char*)p)[sz]) != magic; sz -= c) {
- if(c<=0 || sz<(c+2*SIZE_SZ)) return NULL;
+ else
+ {
+ unsigned long offset, page_mask = GLRO (dl_pagesize) - 1;
+
+ /* mmap()ed chunks have MALLOC_ALIGNMENT or higher power-of-two
+ alignment relative to the beginning of a page. Check this
+ first. */
+ offset = (unsigned long) mem & page_mask;
+ if ((offset != MALLOC_ALIGNMENT && offset != 0 && offset != 0x10 &&
+ offset != 0x20 && offset != 0x40 && offset != 0x80 && offset != 0x100 &&
+ offset != 0x200 && offset != 0x400 && offset != 0x800 && offset != 0x1000 &&
+ offset < 0x2000) ||
+ !chunk_is_mmapped (p) || prev_inuse (p) ||
+ ((((unsigned long) p - prev_size (p)) & page_mask) != 0) ||
+ ((prev_size (p) + sz) & page_mask) != 0)
+ return NULL;
+
+ for (sz -= 1; (c = ((unsigned char *) p)[sz]) != magic; sz -= c)
+ {
+ if (c == 0 || sz < (c + 2 * SIZE_SZ))
+ return NULL;
+ }
}
- }
- ((unsigned char*)p)[sz] ^= 0xFF;
+ ((unsigned char *) p)[sz] ^= 0xFF;
if (magic_p)
- *magic_p = (unsigned char *)p + sz;
+ *magic_p = (unsigned char *) p + sz;
return p;
}
-/* Check for corruption of the top chunk, and try to recover if
- necessary. */
-
-static int
-internal_function
-top_check(void)
+/* Check for corruption of the top chunk. */
+static void
+top_check (void)
{
- mchunkptr t = top(&main_arena);
- char* brk, * new_brk;
- INTERNAL_SIZE_T front_misalign, sbrk_size;
- unsigned long pagesz = GLRO(dl_pagesize);
-
- if (t == initial_top(&main_arena) ||
- (!chunk_is_mmapped(t) &&
- chunksize(t)>=MINSIZE &&
- prev_inuse(t) &&
- (!contiguous(&main_arena) ||
- (char*)t + chunksize(t) == mp_.sbrk_base + main_arena.system_mem)))
- return 0;
-
- malloc_printerr (check_action, "malloc: top chunk is corrupt", t);
-
- /* Try to set up a new top chunk. */
- brk = MORECORE(0);
- front_misalign = (unsigned long)chunk2mem(brk) & MALLOC_ALIGN_MASK;
- if (front_misalign > 0)
- front_misalign = MALLOC_ALIGNMENT - front_misalign;
- sbrk_size = front_misalign + mp_.top_pad + MINSIZE;
- sbrk_size += pagesz - ((unsigned long)(brk + sbrk_size) & (pagesz - 1));
- new_brk = (char*)(MORECORE (sbrk_size));
- if (new_brk == (char*)(MORECORE_FAILURE))
- {
- __set_errno (ENOMEM);
- return -1;
- }
- /* Call the `morecore' hook if necessary. */
- void (*hook) (void) = force_reg (__after_morecore_hook);
- if (hook)
- (*hook) ();
- main_arena.system_mem = (new_brk - mp_.sbrk_base) + sbrk_size;
-
- top(&main_arena) = (mchunkptr)(brk + front_misalign);
- set_head(top(&main_arena), (sbrk_size - front_misalign) | PREV_INUSE);
+ mchunkptr t = top (&main_arena);
+
+ if (t == initial_top (&main_arena) ||
+ (!chunk_is_mmapped (t) &&
+ chunksize (t) >= MINSIZE &&
+ prev_inuse (t) &&
+ (!contiguous (&main_arena) ||
+ (char *) t + chunksize (t) == mp_.sbrk_base + main_arena.system_mem)))
+ return;
- return 0;
+ malloc_printerr ("malloc: top chunk is corrupt");
}
-static void*
-malloc_check(size_t sz, const void *caller)
+static void *
+malloc_check (size_t sz, const void *caller)
{
void *victim;
+ size_t nb;
- if (sz+1 == 0) {
- __set_errno (ENOMEM);
- return NULL;
- }
+ if (__builtin_add_overflow (sz, 1, &nb))
+ {
+ __set_errno (ENOMEM);
+ return NULL;
+ }
- (void)mutex_lock(&main_arena.mutex);
- victim = (top_check() >= 0) ? _int_malloc(&main_arena, sz+1) : NULL;
- (void)mutex_unlock(&main_arena.mutex);
- return mem2mem_check(victim, sz);
+ __libc_lock_lock (main_arena.mutex);
+ top_check ();
+ victim = _int_malloc (&main_arena, nb);
+ __libc_lock_unlock (main_arena.mutex);
+ return mem2mem_check (victim, sz);
}
static void
-free_check(void* mem, const void *caller)
+free_check (void *mem, const void *caller)
{
mchunkptr p;
- if(!mem) return;
- (void)mutex_lock(&main_arena.mutex);
- p = mem2chunk_check(mem, NULL);
- if(!p) {
- (void)mutex_unlock(&main_arena.mutex);
-
- malloc_printerr(check_action, "free(): invalid pointer", mem);
- return;
- }
- if (chunk_is_mmapped(p)) {
- (void)mutex_unlock(&main_arena.mutex);
- munmap_chunk(p);
+ if (!mem)
return;
- }
- _int_free(&main_arena, p, 1);
- (void)mutex_unlock(&main_arena.mutex);
+
+ __libc_lock_lock (main_arena.mutex);
+ p = mem2chunk_check (mem, NULL);
+ if (!p)
+ malloc_printerr ("free(): invalid pointer");
+ if (chunk_is_mmapped (p))
+ {
+ __libc_lock_unlock (main_arena.mutex);
+ munmap_chunk (p);
+ return;
+ }
+ _int_free (&main_arena, p, 1);
+ __libc_lock_unlock (main_arena.mutex);
}
-static void*
-realloc_check(void* oldmem, size_t bytes, const void *caller)
+static void *
+realloc_check (void *oldmem, size_t bytes, const void *caller)
{
INTERNAL_SIZE_T nb;
- void* newmem = 0;
+ void *newmem = 0;
unsigned char *magic_p;
+ size_t rb;
- if (bytes+1 == 0) {
- __set_errno (ENOMEM);
- return NULL;
- }
- if (oldmem == 0) return malloc_check(bytes, NULL);
- if (bytes == 0) {
- free_check (oldmem, NULL);
- return NULL;
- }
- (void)mutex_lock(&main_arena.mutex);
- const mchunkptr oldp = mem2chunk_check(oldmem, &magic_p);
- (void)mutex_unlock(&main_arena.mutex);
- if(!oldp) {
- malloc_printerr(check_action, "realloc(): invalid pointer", oldmem);
- return malloc_check(bytes, NULL);
- }
- const INTERNAL_SIZE_T oldsize = chunksize(oldp);
+ if (__builtin_add_overflow (bytes, 1, &rb))
+ {
+ __set_errno (ENOMEM);
+ return NULL;
+ }
+ if (oldmem == 0)
+ return malloc_check (bytes, NULL);
- checked_request2size(bytes+1, nb);
- (void)mutex_lock(&main_arena.mutex);
+ if (bytes == 0)
+ {
+ free_check (oldmem, NULL);
+ return NULL;
+ }
+ __libc_lock_lock (main_arena.mutex);
+ const mchunkptr oldp = mem2chunk_check (oldmem, &magic_p);
+ __libc_lock_unlock (main_arena.mutex);
+ if (!oldp)
+ malloc_printerr ("realloc(): invalid pointer");
+ const INTERNAL_SIZE_T oldsize = chunksize (oldp);
+
+ if (!checked_request2size (rb, &nb))
+ goto invert;
- if (chunk_is_mmapped(oldp)) {
+ __libc_lock_lock (main_arena.mutex);
+
+ if (chunk_is_mmapped (oldp))
+ {
#if HAVE_MREMAP
- mchunkptr newp = mremap_chunk(oldp, nb);
- if(newp)
- newmem = chunk2mem(newp);
- else
+ mchunkptr newp = mremap_chunk (oldp, nb);
+ if (newp)
+ newmem = chunk2mem (newp);
+ else
#endif
- {
- /* Note the extra SIZE_SZ overhead. */
- if(oldsize - SIZE_SZ >= nb)
- newmem = oldmem; /* do nothing */
- else {
- /* Must alloc, copy, free. */
- if (top_check() >= 0)
- newmem = _int_malloc(&main_arena, bytes+1);
- if (newmem) {
- MALLOC_COPY(newmem, oldmem, oldsize - 2*SIZE_SZ);
- munmap_chunk(oldp);
- }
+ {
+ /* Note the extra SIZE_SZ overhead. */
+ if (oldsize - SIZE_SZ >= nb)
+ newmem = oldmem; /* do nothing */
+ else
+ {
+ /* Must alloc, copy, free. */
+ top_check ();
+ newmem = _int_malloc (&main_arena, rb);
+ if (newmem)
+ {
+ memcpy (newmem, oldmem, oldsize - 2 * SIZE_SZ);
+ munmap_chunk (oldp);
+ }
+ }
}
}
- } else {
- if (top_check() >= 0) {
- INTERNAL_SIZE_T nb;
- checked_request2size(bytes + 1, nb);
- newmem = _int_realloc(&main_arena, oldp, oldsize, nb);
+ else
+ {
+ top_check ();
+ newmem = _int_realloc (&main_arena, oldp, oldsize, nb);
}
- }
+ DIAG_PUSH_NEEDS_COMMENT;
+#if __GNUC_PREREQ (7, 0)
+ /* GCC 7 warns about magic_p may be used uninitialized. But we never
+ reach here if magic_p is uninitialized. */
+ DIAG_IGNORE_NEEDS_COMMENT (7, "-Wmaybe-uninitialized");
+#endif
/* mem2chunk_check changed the magic byte in the old chunk.
If newmem is NULL, then the old chunk will still be used though,
so we need to invert that change here. */
- if (newmem == NULL) *magic_p ^= 0xFF;
+invert:
+ if (newmem == NULL)
+ *magic_p ^= 0xFF;
+ DIAG_POP_NEEDS_COMMENT;
- (void)mutex_unlock(&main_arena.mutex);
+ __libc_lock_unlock (main_arena.mutex);
- return mem2mem_check(newmem, bytes);
+ return mem2mem_check (newmem, bytes);
}
-static void*
-memalign_check(size_t alignment, size_t bytes, const void *caller)
+static void *
+memalign_check (size_t alignment, size_t bytes, const void *caller)
{
- void* mem;
+ void *mem;
- if (alignment <= MALLOC_ALIGNMENT) return malloc_check(bytes, NULL);
- if (alignment < MINSIZE) alignment = MINSIZE;
+ if (alignment <= MALLOC_ALIGNMENT)
+ return malloc_check (bytes, NULL);
- if (bytes+1 == 0) {
- __set_errno (ENOMEM);
- return NULL;
- }
- (void)mutex_lock(&main_arena.mutex);
- mem = (top_check() >= 0) ? _int_memalign(&main_arena, alignment, bytes+1) :
- NULL;
- (void)mutex_unlock(&main_arena.mutex);
- return mem2mem_check(mem, bytes);
+ if (alignment < MINSIZE)
+ alignment = MINSIZE;
+
+ /* If the alignment is greater than SIZE_MAX / 2 + 1 it cannot be a
+ power of 2 and will cause overflow in the check below. */
+ if (alignment > SIZE_MAX / 2 + 1)
+ {
+ __set_errno (EINVAL);
+ return 0;
+ }
+
+ /* Check for overflow. */
+ if (bytes > SIZE_MAX - alignment - MINSIZE)
+ {
+ __set_errno (ENOMEM);
+ return 0;
+ }
+
+ /* Make sure alignment is power of 2. */
+ if (!powerof2 (alignment))
+ {
+ size_t a = MALLOC_ALIGNMENT * 2;
+ while (a < alignment)
+ a <<= 1;
+ alignment = a;
+ }
+
+ __libc_lock_lock (main_arena.mutex);
+ top_check ();
+ mem = _int_memalign (&main_arena, alignment, bytes + 1);
+ __libc_lock_unlock (main_arena.mutex);
+ return mem2mem_check (mem, bytes);
}
+#if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_25)
-/* Get/set state: malloc_get_state() records the current state of all
- malloc variables (_except_ for the actual heap contents and `hook'
- function pointers) in a system dependent, opaque data structure.
- This data structure is dynamically allocated and can be free()d
- after use. malloc_set_state() restores the state of all malloc
- variables to the previously obtained state. This is especially
- useful when using this malloc as part of a shared library, and when
- the heap contents are saved/restored via some other method. The
- primary example for this is GNU Emacs with its `dumping' procedure.
- `Hook' function pointers are never saved or restored by these
- functions, with two exceptions: If malloc checking was in use when
- malloc_get_state() was called, then malloc_set_state() calls
- __malloc_check_init() if possible; if malloc checking was not in
- use in the recorded state but the user requested malloc checking,
- then the hooks are reset to 0. */
+/* Support for restoring dumped heaps contained in historic Emacs
+ executables. The heap saving feature (malloc_get_state) is no
+ longer implemented in this version of glibc, but we have a heap
+ rewriter in malloc_set_state which transforms the heap into a
+ version compatible with current malloc. */
#define MALLOC_STATE_MAGIC 0x444c4541l
-#define MALLOC_STATE_VERSION (0*0x100l + 4l) /* major*0x100 + minor */
-
-struct malloc_save_state {
- long magic;
- long version;
- mbinptr av[NBINS * 2 + 2];
- char* sbrk_base;
- int sbrked_mem_bytes;
+#define MALLOC_STATE_VERSION (0 * 0x100l + 5l) /* major*0x100 + minor */
+
+struct malloc_save_state
+{
+ long magic;
+ long version;
+ mbinptr av[NBINS * 2 + 2];
+ char *sbrk_base;
+ int sbrked_mem_bytes;
unsigned long trim_threshold;
unsigned long top_pad;
- unsigned int n_mmaps_max;
+ unsigned int n_mmaps_max;
unsigned long mmap_threshold;
- int check_action;
+ int check_action;
unsigned long max_sbrked_mem;
- unsigned long max_total_mem;
- unsigned int n_mmaps;
- unsigned int max_n_mmaps;
+ unsigned long max_total_mem; /* Always 0, for backwards compatibility. */
+ unsigned int n_mmaps;
+ unsigned int max_n_mmaps;
unsigned long mmapped_mem;
unsigned long max_mmapped_mem;
- int using_malloc_checking;
+ int using_malloc_checking;
unsigned long max_fast;
unsigned long arena_test;
unsigned long arena_max;
unsigned long narenas;
};
-void*
-__malloc_get_state(void)
+/* Dummy implementation which always fails. We need to provide this
+ symbol so that existing Emacs binaries continue to work with
+ BIND_NOW. */
+void *
+attribute_compat_text_section
+malloc_get_state (void)
{
- struct malloc_save_state* ms;
- int i;
- mbinptr b;
-
- ms = (struct malloc_save_state*)__libc_malloc(sizeof(*ms));
- if (!ms)
- return 0;
- (void)mutex_lock(&main_arena.mutex);
- malloc_consolidate(&main_arena);
- ms->magic = MALLOC_STATE_MAGIC;
- ms->version = MALLOC_STATE_VERSION;
- ms->av[0] = 0;
- ms->av[1] = 0; /* used to be binblocks, now no longer used */
- ms->av[2] = top(&main_arena);
- ms->av[3] = 0; /* used to be undefined */
- for(i=1; i<NBINS; i++) {
- b = bin_at(&main_arena, i);
- if(first(b) == b)
- ms->av[2*i+2] = ms->av[2*i+3] = 0; /* empty bin */
- else {
- ms->av[2*i+2] = first(b);
- ms->av[2*i+3] = last(b);
- }
- }
- ms->sbrk_base = mp_.sbrk_base;
- ms->sbrked_mem_bytes = main_arena.system_mem;
- ms->trim_threshold = mp_.trim_threshold;
- ms->top_pad = mp_.top_pad;
- ms->n_mmaps_max = mp_.n_mmaps_max;
- ms->mmap_threshold = mp_.mmap_threshold;
- ms->check_action = check_action;
- ms->max_sbrked_mem = main_arena.max_system_mem;
- ms->max_total_mem = 0;
- ms->n_mmaps = mp_.n_mmaps;
- ms->max_n_mmaps = mp_.max_n_mmaps;
- ms->mmapped_mem = mp_.mmapped_mem;
- ms->max_mmapped_mem = mp_.max_mmapped_mem;
- ms->using_malloc_checking = using_malloc_checking;
- ms->max_fast = get_max_fast();
-#ifdef PER_THREAD
- ms->arena_test = mp_.arena_test;
- ms->arena_max = mp_.arena_max;
- ms->narenas = narenas;
-#endif
- (void)mutex_unlock(&main_arena.mutex);
- return (void*)ms;
+ __set_errno (ENOSYS);
+ return NULL;
}
+compat_symbol (libc, malloc_get_state, malloc_get_state, GLIBC_2_0);
int
-__malloc_set_state(void* msptr)
+attribute_compat_text_section
+malloc_set_state (void *msptr)
{
- struct malloc_save_state* ms = (struct malloc_save_state*)msptr;
- size_t i;
- mbinptr b;
+ struct malloc_save_state *ms = (struct malloc_save_state *) msptr;
+
+ if (ms->magic != MALLOC_STATE_MAGIC)
+ return -1;
- disallow_malloc_check = 1;
- ptmalloc_init();
- if(ms->magic != MALLOC_STATE_MAGIC) return -1;
/* Must fail if the major version is too high. */
- if((ms->version & ~0xffl) > (MALLOC_STATE_VERSION & ~0xffl)) return -2;
- (void)mutex_lock(&main_arena.mutex);
- /* There are no fastchunks. */
- clear_fastchunks(&main_arena);
- if (ms->version >= 4)
- set_max_fast(ms->max_fast);
- else
- set_max_fast(64); /* 64 used to be the value we always used. */
- for (i=0; i<NFASTBINS; ++i)
- fastbin (&main_arena, i) = 0;
- for (i=0; i<BINMAPSIZE; ++i)
- main_arena.binmap[i] = 0;
- top(&main_arena) = ms->av[2];
- main_arena.last_remainder = 0;
- for(i=1; i<NBINS; i++) {
- b = bin_at(&main_arena, i);
- if(ms->av[2*i+2] == 0) {
- assert(ms->av[2*i+3] == 0);
- first(b) = last(b) = b;
- } else {
- if(ms->version >= 3 &&
- (i<NSMALLBINS || (largebin_index(chunksize(ms->av[2*i+2]))==i &&
- largebin_index(chunksize(ms->av[2*i+3]))==i))) {
- first(b) = ms->av[2*i+2];
- last(b) = ms->av[2*i+3];
- /* Make sure the links to the bins within the heap are correct. */
- first(b)->bk = b;
- last(b)->fd = b;
- /* Set bit in binblocks. */
- mark_bin(&main_arena, i);
- } else {
- /* Oops, index computation from chunksize must have changed.
- Link the whole list into unsorted_chunks. */
- first(b) = last(b) = b;
- b = unsorted_chunks(&main_arena);
- ms->av[2*i+2]->bk = b;
- ms->av[2*i+3]->fd = b->fd;
- b->fd->bk = ms->av[2*i+3];
- b->fd = ms->av[2*i+2];
- }
- }
- }
- if (ms->version < 3) {
- /* Clear fd_nextsize and bk_nextsize fields. */
- b = unsorted_chunks(&main_arena)->fd;
- while (b != unsorted_chunks(&main_arena)) {
- if (!in_smallbin_range(chunksize(b))) {
- b->fd_nextsize = NULL;
- b->bk_nextsize = NULL;
- }
- b = b->fd;
- }
+ if ((ms->version & ~0xffl) > (MALLOC_STATE_VERSION & ~0xffl))
+ return -2;
+
+ /* We do not need to perform locking here because malloc_set_state
+ must be called before the first call into the malloc subsytem
+ (usually via __malloc_initialize_hook). pthread_create always
+ calls calloc and thus must be called only afterwards, so there
+ cannot be more than one thread when we reach this point. */
+
+ /* Disable the malloc hooks (and malloc checking). */
+ __malloc_hook = NULL;
+ __realloc_hook = NULL;
+ __free_hook = NULL;
+ __memalign_hook = NULL;
+ using_malloc_checking = 0;
+
+ /* Patch the dumped heap. We no longer try to integrate into the
+ existing heap. Instead, we mark the existing chunks as mmapped.
+ Together with the update to dumped_main_arena_start and
+ dumped_main_arena_end, realloc and free will recognize these
+ chunks as dumped fake mmapped chunks and never free them. */
+
+ /* Find the chunk with the lowest address with the heap. */
+ mchunkptr chunk = NULL;
+ {
+ size_t *candidate = (size_t *) ms->sbrk_base;
+ size_t *end = (size_t *) (ms->sbrk_base + ms->sbrked_mem_bytes);
+ while (candidate < end)
+ if (*candidate != 0)
+ {
+ chunk = mem2chunk ((void *) (candidate + 1));
+ break;
+ }
+ else
+ ++candidate;
}
- mp_.sbrk_base = ms->sbrk_base;
- main_arena.system_mem = ms->sbrked_mem_bytes;
- mp_.trim_threshold = ms->trim_threshold;
- mp_.top_pad = ms->top_pad;
- mp_.n_mmaps_max = ms->n_mmaps_max;
- mp_.mmap_threshold = ms->mmap_threshold;
- check_action = ms->check_action;
- main_arena.max_system_mem = ms->max_sbrked_mem;
- mp_.n_mmaps = ms->n_mmaps;
- mp_.max_n_mmaps = ms->max_n_mmaps;
- mp_.mmapped_mem = ms->mmapped_mem;
- mp_.max_mmapped_mem = ms->max_mmapped_mem;
- /* add version-dependent code here */
- if (ms->version >= 1) {
- /* Check whether it is safe to enable malloc checking, or whether
- it is necessary to disable it. */
- if (ms->using_malloc_checking && !using_malloc_checking &&
- !disallow_malloc_check)
- __malloc_check_init ();
- else if (!ms->using_malloc_checking && using_malloc_checking) {
- __malloc_hook = NULL;
- __free_hook = NULL;
- __realloc_hook = NULL;
- __memalign_hook = NULL;
- using_malloc_checking = 0;
+ if (chunk == NULL)
+ return 0;
+
+ /* Iterate over the dumped heap and patch the chunks so that they
+ are treated as fake mmapped chunks. */
+ mchunkptr top = ms->av[2];
+ while (chunk < top)
+ {
+ if (inuse (chunk))
+ {
+ /* Mark chunk as mmapped, to trigger the fallback path. */
+ size_t size = chunksize (chunk);
+ set_head (chunk, size | IS_MMAPPED);
+ }
+ chunk = next_chunk (chunk);
}
- }
- if (ms->version >= 4) {
-#ifdef PER_THREAD
- mp_.arena_test = ms->arena_test;
- mp_.arena_max = ms->arena_max;
- narenas = ms->narenas;
-#endif
- }
- check_malloc_state(&main_arena);
- (void)mutex_unlock(&main_arena.mutex);
+ /* The dumped fake mmapped chunks all lie in this address range. */
+ dumped_main_arena_start = (mchunkptr) ms->sbrk_base;
+ dumped_main_arena_end = top;
+
return 0;
}
+compat_symbol (libc, malloc_set_state, malloc_set_state, GLIBC_2_0);
+
+#endif /* SHLIB_COMPAT */
/*
* Local variables:
projects / thirdparty / glibc.git / blobdiff