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freebsd-nq/sys/kern/kern_malloc.c
Matthew D Fleming e3813573bd Rework memguard(9) to reserve significantly more KVA to detect 
use-after-free over a longer time.  Also release the backing pages of
a guarded allocation at free(9) time to reduce the overhead of using
memguard(9).  Allow setting and varying the malloc type at run-time.
Add knobs to allow:

 - randomly guarding memory
 - adding un-backed KVA guard pages to detect underflow and overflow
 - a lower limit on the size of allocations that are guarded

Reviewed by:    alc
Reviewed by:    brueffer, Ulrich Spörlein <uqs spoerlein net> (man page)
Silence from:   -arch
Approved by:    zml (mentor)
MFC after:      1 month
2010-08-11 22:10:37 +00:00

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/*-
* Copyright (c) 1987, 1991, 1993
* The Regents of the University of California.
* Copyright (c) 2005-2009 Robert N. M. Watson
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. 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.
* 4. Neither the name of the University 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 REGENTS 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 REGENTS 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.
*
* @(#)kern_malloc.c 8.3 (Berkeley) 1/4/94
*/
/*
* Kernel malloc(9) implementation -- general purpose kernel memory allocator
* based on memory types. Back end is implemented using the UMA(9) zone
* allocator. A set of fixed-size buckets are used for smaller allocations,
* and a special UMA allocation interface is used for larger allocations.
* Callers declare memory types, and statistics are maintained independently
* for each memory type. Statistics are maintained per-CPU for performance
* reasons. See malloc(9) and comments in malloc.h for a detailed
* description.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_ddb.h"
#include "opt_kdtrace.h"
#include "opt_vm.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kdb.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/mutex.h>
#include <sys/vmmeter.h>
#include <sys/proc.h>
#include <sys/sbuf.h>
#include <sys/sysctl.h>
#include <sys/time.h>
#include <vm/vm.h>
#include <vm/pmap.h>
#include <vm/vm_param.h>
#include <vm/vm_kern.h>
#include <vm/vm_extern.h>
#include <vm/vm_map.h>
#include <vm/vm_page.h>
#include <vm/uma.h>
#include <vm/uma_int.h>
#include <vm/uma_dbg.h>
#ifdef DEBUG_MEMGUARD
#include <vm/memguard.h>
#endif
#ifdef DEBUG_REDZONE
#include <vm/redzone.h>
#endif
#if defined(INVARIANTS) && defined(__i386__)
#include <machine/cpu.h>
#endif
#include <ddb/ddb.h>
#ifdef KDTRACE_HOOKS
#include <sys/dtrace_bsd.h>
dtrace_malloc_probe_func_t dtrace_malloc_probe;
#endif
/*
* When realloc() is called, if the new size is sufficiently smaller than
* the old size, realloc() will allocate a new, smaller block to avoid
* wasting memory. 'Sufficiently smaller' is defined as: newsize <=
* oldsize / 2^n, where REALLOC_FRACTION defines the value of 'n'.
*/
#ifndef REALLOC_FRACTION
#define REALLOC_FRACTION 1 /* new block if <= half the size */
#endif
/*
* Centrally define some common malloc types.
*/
MALLOC_DEFINE(M_CACHE, "cache", "Various Dynamically allocated caches");
MALLOC_DEFINE(M_DEVBUF, "devbuf", "device driver memory");
MALLOC_DEFINE(M_TEMP, "temp", "misc temporary data buffers");
MALLOC_DEFINE(M_IP6OPT, "ip6opt", "IPv6 options");
MALLOC_DEFINE(M_IP6NDP, "ip6ndp", "IPv6 Neighbor Discovery");
static void kmeminit(void *);
SYSINIT(kmem, SI_SUB_KMEM, SI_ORDER_FIRST, kmeminit, NULL);
static MALLOC_DEFINE(M_FREE, "free", "should be on free list");
static struct malloc_type *kmemstatistics;
static vm_offset_t kmembase;
static vm_offset_t kmemlimit;
static int kmemcount;
#define KMEM_ZSHIFT 4
#define KMEM_ZBASE 16
#define KMEM_ZMASK (KMEM_ZBASE - 1)
#define KMEM_ZMAX PAGE_SIZE
#define KMEM_ZSIZE (KMEM_ZMAX >> KMEM_ZSHIFT)
static uint8_t kmemsize[KMEM_ZSIZE + 1];
#ifndef MALLOC_DEBUG_MAXZONES
#define MALLOC_DEBUG_MAXZONES 1
#endif
static int numzones = MALLOC_DEBUG_MAXZONES;
/*
* Small malloc(9) memory allocations are allocated from a set of UMA buckets
* of various sizes.
*
* XXX: The comment here used to read "These won't be powers of two for
* long." It's possible that a significant amount of wasted memory could be
* recovered by tuning the sizes of these buckets.
*/
struct {
int kz_size;
char *kz_name;
uma_zone_t kz_zone[MALLOC_DEBUG_MAXZONES];
} kmemzones[] = {
{16, "16", },
{32, "32", },
{64, "64", },
{128, "128", },
{256, "256", },
{512, "512", },
{1024, "1024", },
{2048, "2048", },
{4096, "4096", },
#if PAGE_SIZE > 4096
{8192, "8192", },
#if PAGE_SIZE > 8192
{16384, "16384", },
#if PAGE_SIZE > 16384
{32768, "32768", },
#if PAGE_SIZE > 32768
{65536, "65536", },
#if PAGE_SIZE > 65536
#error "Unsupported PAGE_SIZE"
#endif /* 65536 */
#endif /* 32768 */
#endif /* 16384 */
#endif /* 8192 */
#endif /* 4096 */
{0, NULL},
};
/*
* Zone to allocate malloc type descriptions from. For ABI reasons, memory
* types are described by a data structure passed by the declaring code, but
* the malloc(9) implementation has its own data structure describing the
* type and statistics. This permits the malloc(9)-internal data structures
* to be modified without breaking binary-compiled kernel modules that
* declare malloc types.
*/
static uma_zone_t mt_zone;
u_long vm_kmem_size;
SYSCTL_ULONG(_vm, OID_AUTO, kmem_size, CTLFLAG_RD, &vm_kmem_size, 0,
"Size of kernel memory");
static u_long vm_kmem_size_min;
SYSCTL_ULONG(_vm, OID_AUTO, kmem_size_min, CTLFLAG_RD, &vm_kmem_size_min, 0,
"Minimum size of kernel memory");
static u_long vm_kmem_size_max;
SYSCTL_ULONG(_vm, OID_AUTO, kmem_size_max, CTLFLAG_RD, &vm_kmem_size_max, 0,
"Maximum size of kernel memory");
static u_int vm_kmem_size_scale;
SYSCTL_UINT(_vm, OID_AUTO, kmem_size_scale, CTLFLAG_RD, &vm_kmem_size_scale, 0,
"Scale factor for kernel memory size");
/*
* The malloc_mtx protects the kmemstatistics linked list.
*/
struct mtx malloc_mtx;
#ifdef MALLOC_PROFILE
uint64_t krequests[KMEM_ZSIZE + 1];
static int sysctl_kern_mprof(SYSCTL_HANDLER_ARGS);
#endif
static int sysctl_kern_malloc_stats(SYSCTL_HANDLER_ARGS);
/*
* time_uptime of the last malloc(9) failure (induced or real).
*/
static time_t t_malloc_fail;
#if defined(MALLOC_MAKE_FAILURES) || (MALLOC_DEBUG_MAXZONES > 1)
SYSCTL_NODE(_debug, OID_AUTO, malloc, CTLFLAG_RD, 0,
"Kernel malloc debugging options");
#endif
/*
* malloc(9) fault injection -- cause malloc failures every (n) mallocs when
* the caller specifies M_NOWAIT. If set to 0, no failures are caused.
*/
#ifdef MALLOC_MAKE_FAILURES
static int malloc_failure_rate;
static int malloc_nowait_count;
static int malloc_failure_count;
SYSCTL_INT(_debug_malloc, OID_AUTO, failure_rate, CTLFLAG_RW,
&malloc_failure_rate, 0, "Every (n) mallocs with M_NOWAIT will fail");
TUNABLE_INT("debug.malloc.failure_rate", &malloc_failure_rate);
SYSCTL_INT(_debug_malloc, OID_AUTO, failure_count, CTLFLAG_RD,
&malloc_failure_count, 0, "Number of imposed M_NOWAIT malloc failures");
#endif
/*
* malloc(9) uma zone separation -- sub-page buffer overruns in one
* malloc type will affect only a subset of other malloc types.
*/
#if MALLOC_DEBUG_MAXZONES > 1
static void
tunable_set_numzones(void)
{
TUNABLE_INT_FETCH("debug.malloc.numzones",
&numzones);
/* Sanity check the number of malloc uma zones. */
if (numzones <= 0)
numzones = 1;
if (numzones > MALLOC_DEBUG_MAXZONES)
numzones = MALLOC_DEBUG_MAXZONES;
}
SYSINIT(numzones, SI_SUB_TUNABLES, SI_ORDER_ANY, tunable_set_numzones, NULL);
SYSCTL_INT(_debug_malloc, OID_AUTO, numzones, CTLFLAG_RDTUN,
&numzones, 0, "Number of malloc uma subzones");
/*
* Any number that changes regularly is an okay choice for the
* offset. Build numbers are pretty good of you have them.
*/
static u_int zone_offset = __FreeBSD_version;
TUNABLE_INT("debug.malloc.zone_offset", &zone_offset);
SYSCTL_UINT(_debug_malloc, OID_AUTO, zone_offset, CTLFLAG_RDTUN,
&zone_offset, 0, "Separate malloc types by examining the "
"Nth character in the malloc type short description.");
static u_int
mtp_get_subzone(const char *desc)
{
size_t len;
u_int val;
if (desc == NULL || (len = strlen(desc)) == 0)
return (0);
val = desc[zone_offset % len];
return (val % numzones);
}
#elif MALLOC_DEBUG_MAXZONES == 0
#error "MALLOC_DEBUG_MAXZONES must be positive."
#else
static inline u_int
mtp_get_subzone(const char *desc)
{
return (0);
}
#endif /* MALLOC_DEBUG_MAXZONES > 1 */
int
malloc_last_fail(void)
{
return (time_uptime - t_malloc_fail);
}
/*
* An allocation has succeeded -- update malloc type statistics for the
* amount of bucket size. Occurs within a critical section so that the
* thread isn't preempted and doesn't migrate while updating per-PCU
* statistics.
*/
static void
malloc_type_zone_allocated(struct malloc_type *mtp, unsigned long size,
int zindx)
{
struct malloc_type_internal *mtip;
struct malloc_type_stats *mtsp;
critical_enter();
mtip = mtp->ks_handle;
mtsp = &mtip->mti_stats[curcpu];
if (size > 0) {
mtsp->mts_memalloced += size;
mtsp->mts_numallocs++;
}
if (zindx != -1)
mtsp->mts_size |= 1 << zindx;
#ifdef KDTRACE_HOOKS
if (dtrace_malloc_probe != NULL) {
uint32_t probe_id = mtip->mti_probes[DTMALLOC_PROBE_MALLOC];
if (probe_id != 0)
(dtrace_malloc_probe)(probe_id,
(uintptr_t) mtp, (uintptr_t) mtip,
(uintptr_t) mtsp, size, zindx);
}
#endif
critical_exit();
}
void
malloc_type_allocated(struct malloc_type *mtp, unsigned long size)
{
if (size > 0)
malloc_type_zone_allocated(mtp, size, -1);
}
/*
* A free operation has occurred -- update malloc type statistics for the
* amount of the bucket size. Occurs within a critical section so that the
* thread isn't preempted and doesn't migrate while updating per-CPU
* statistics.
*/
void
malloc_type_freed(struct malloc_type *mtp, unsigned long size)
{
struct malloc_type_internal *mtip;
struct malloc_type_stats *mtsp;
critical_enter();
mtip = mtp->ks_handle;
mtsp = &mtip->mti_stats[curcpu];
mtsp->mts_memfreed += size;
mtsp->mts_numfrees++;
#ifdef KDTRACE_HOOKS
if (dtrace_malloc_probe != NULL) {
uint32_t probe_id = mtip->mti_probes[DTMALLOC_PROBE_FREE];
if (probe_id != 0)
(dtrace_malloc_probe)(probe_id,
(uintptr_t) mtp, (uintptr_t) mtip,
(uintptr_t) mtsp, size, 0);
}
#endif
critical_exit();
}
/*
* malloc:
*
* Allocate a block of memory.
*
* If M_NOWAIT is set, this routine will not block and return NULL if
* the allocation fails.
*/
void *
malloc(unsigned long size, struct malloc_type *mtp, int flags)
{
int indx;
struct malloc_type_internal *mtip;
caddr_t va;
uma_zone_t zone;
#if defined(DIAGNOSTIC) || defined(DEBUG_REDZONE)
unsigned long osize = size;
#endif
#ifdef INVARIANTS
KASSERT(mtp->ks_magic == M_MAGIC, ("malloc: bad malloc type magic"));
/*
* Check that exactly one of M_WAITOK or M_NOWAIT is specified.
*/
indx = flags & (M_WAITOK | M_NOWAIT);
if (indx != M_NOWAIT && indx != M_WAITOK) {
static struct timeval lasterr;
static int curerr, once;
if (once == 0 && ppsratecheck(&lasterr, &curerr, 1)) {
printf("Bad malloc flags: %x\n", indx);
kdb_backtrace();
flags |= M_WAITOK;
once++;
}
}
#endif
#ifdef MALLOC_MAKE_FAILURES
if ((flags & M_NOWAIT) && (malloc_failure_rate != 0)) {
atomic_add_int(&malloc_nowait_count, 1);
if ((malloc_nowait_count % malloc_failure_rate) == 0) {
atomic_add_int(&malloc_failure_count, 1);
t_malloc_fail = time_uptime;
return (NULL);
}
}
#endif
if (flags & M_WAITOK)
KASSERT(curthread->td_intr_nesting_level == 0,
("malloc(M_WAITOK) in interrupt context"));
#ifdef DEBUG_MEMGUARD
if (memguard_cmp(mtp, size)) {
va = memguard_alloc(size, flags);
if (va != NULL)
return (va);
/* This is unfortunate but should not be fatal. */
}
#endif
#ifdef DEBUG_REDZONE
size = redzone_size_ntor(size);
#endif
if (size <= KMEM_ZMAX) {
mtip = mtp->ks_handle;
if (size & KMEM_ZMASK)
size = (size & ~KMEM_ZMASK) + KMEM_ZBASE;
indx = kmemsize[size >> KMEM_ZSHIFT];
KASSERT(mtip->mti_zone < numzones,
("mti_zone %u out of range %d",
mtip->mti_zone, numzones));
zone = kmemzones[indx].kz_zone[mtip->mti_zone];
#ifdef MALLOC_PROFILE
krequests[size >> KMEM_ZSHIFT]++;
#endif
va = uma_zalloc(zone, flags);
if (va != NULL)
size = zone->uz_size;
malloc_type_zone_allocated(mtp, va == NULL ? 0 : size, indx);
} else {
size = roundup(size, PAGE_SIZE);
zone = NULL;
va = uma_large_malloc(size, flags);
malloc_type_allocated(mtp, va == NULL ? 0 : size);
}
if (flags & M_WAITOK)
KASSERT(va != NULL, ("malloc(M_WAITOK) returned NULL"));
else if (va == NULL)
t_malloc_fail = time_uptime;
#ifdef DIAGNOSTIC
if (va != NULL && !(flags & M_ZERO)) {
memset(va, 0x70, osize);
}
#endif
#ifdef DEBUG_REDZONE
if (va != NULL)
va = redzone_setup(va, osize);
#endif
return ((void *) va);
}
/*
* free:
*
* Free a block of memory allocated by malloc.
*
* This routine may not block.
*/
void
free(void *addr, struct malloc_type *mtp)
{
uma_slab_t slab;
u_long size;
KASSERT(mtp->ks_magic == M_MAGIC, ("free: bad malloc type magic"));
/* free(NULL, ...) does nothing */
if (addr == NULL)
return;
#ifdef DEBUG_MEMGUARD
if (is_memguard_addr(addr)) {
memguard_free(addr);
return;
}
#endif
#ifdef DEBUG_REDZONE
redzone_check(addr);
addr = redzone_addr_ntor(addr);
#endif
slab = vtoslab((vm_offset_t)addr & (~UMA_SLAB_MASK));
if (slab == NULL)
panic("free: address %p(%p) has not been allocated.\n",
addr, (void *)((u_long)addr & (~UMA_SLAB_MASK)));
if (!(slab->us_flags & UMA_SLAB_MALLOC)) {
#ifdef INVARIANTS
struct malloc_type **mtpp = addr;
#endif
size = slab->us_keg->uk_size;
#ifdef INVARIANTS
/*
* Cache a pointer to the malloc_type that most recently freed
* this memory here. This way we know who is most likely to
* have stepped on it later.
*
* This code assumes that size is a multiple of 8 bytes for
* 64 bit machines
*/
mtpp = (struct malloc_type **)
((unsigned long)mtpp & ~UMA_ALIGN_PTR);
mtpp += (size - sizeof(struct malloc_type *)) /
sizeof(struct malloc_type *);
*mtpp = mtp;
#endif
uma_zfree_arg(LIST_FIRST(&slab->us_keg->uk_zones), addr, slab);
} else {
size = slab->us_size;
uma_large_free(slab);
}
malloc_type_freed(mtp, size);
}
/*
* realloc: change the size of a memory block
*/
void *
realloc(void *addr, unsigned long size, struct malloc_type *mtp, int flags)
{
uma_slab_t slab;
unsigned long alloc;
void *newaddr;
KASSERT(mtp->ks_magic == M_MAGIC,
("realloc: bad malloc type magic"));
/* realloc(NULL, ...) is equivalent to malloc(...) */
if (addr == NULL)
return (malloc(size, mtp, flags));
/*
* XXX: Should report free of old memory and alloc of new memory to
* per-CPU stats.
*/
#ifdef DEBUG_MEMGUARD
if (is_memguard_addr(addr)) {
slab = NULL;
alloc = size;
goto remalloc;
}
#endif
#ifdef DEBUG_REDZONE
slab = NULL;
alloc = redzone_get_size(addr);
#else
slab = vtoslab((vm_offset_t)addr & ~(UMA_SLAB_MASK));
/* Sanity check */
KASSERT(slab != NULL,
("realloc: address %p out of range", (void *)addr));
/* Get the size of the original block */
if (!(slab->us_flags & UMA_SLAB_MALLOC))
alloc = slab->us_keg->uk_size;
else
alloc = slab->us_size;
/* Reuse the original block if appropriate */
if (size <= alloc
&& (size > (alloc >> REALLOC_FRACTION) || alloc == MINALLOCSIZE))
return (addr);
#endif /* !DEBUG_REDZONE */
#ifdef DEBUG_MEMGUARD
remalloc:
#endif
/* Allocate a new, bigger (or smaller) block */
if ((newaddr = malloc(size, mtp, flags)) == NULL)
return (NULL);
/* Copy over original contents */
bcopy(addr, newaddr, min(size, alloc));
free(addr, mtp);
return (newaddr);
}
/*
* reallocf: same as realloc() but free memory on failure.
*/
void *
reallocf(void *addr, unsigned long size, struct malloc_type *mtp, int flags)
{
void *mem;
if ((mem = realloc(addr, size, mtp, flags)) == NULL)
free(addr, mtp);
return (mem);
}
/*
* Initialize the kernel memory allocator
*/
/* ARGSUSED*/
static void
kmeminit(void *dummy)
{
uint8_t indx;
u_long mem_size, tmp;
int i;
mtx_init(&malloc_mtx, "malloc", NULL, MTX_DEF);
/*
* Try to auto-tune the kernel memory size, so that it is
* more applicable for a wider range of machine sizes.
* On an X86, a VM_KMEM_SIZE_SCALE value of 4 is good, while
* a VM_KMEM_SIZE of 12MB is a fair compromise. The
* VM_KMEM_SIZE_MAX is dependent on the maximum KVA space
* available, and on an X86 with a total KVA space of 256MB,
* try to keep VM_KMEM_SIZE_MAX at 80MB or below.
*
* Note that the kmem_map is also used by the zone allocator,
* so make sure that there is enough space.
*/
vm_kmem_size = VM_KMEM_SIZE + nmbclusters * PAGE_SIZE;
mem_size = cnt.v_page_count;
#if defined(VM_KMEM_SIZE_SCALE)
vm_kmem_size_scale = VM_KMEM_SIZE_SCALE;
#endif
TUNABLE_INT_FETCH("vm.kmem_size_scale", &vm_kmem_size_scale);
if (vm_kmem_size_scale > 0 &&
(mem_size / vm_kmem_size_scale) > (vm_kmem_size / PAGE_SIZE))
vm_kmem_size = (mem_size / vm_kmem_size_scale) * PAGE_SIZE;
#if defined(VM_KMEM_SIZE_MIN)
vm_kmem_size_min = VM_KMEM_SIZE_MIN;
#endif
TUNABLE_ULONG_FETCH("vm.kmem_size_min", &vm_kmem_size_min);
if (vm_kmem_size_min > 0 && vm_kmem_size < vm_kmem_size_min) {
vm_kmem_size = vm_kmem_size_min;
}
#if defined(VM_KMEM_SIZE_MAX)
vm_kmem_size_max = VM_KMEM_SIZE_MAX;
#endif
TUNABLE_ULONG_FETCH("vm.kmem_size_max", &vm_kmem_size_max);
if (vm_kmem_size_max > 0 && vm_kmem_size >= vm_kmem_size_max)
vm_kmem_size = vm_kmem_size_max;
/* Allow final override from the kernel environment */
TUNABLE_ULONG_FETCH("vm.kmem_size", &vm_kmem_size);
/*
* Limit kmem virtual size to twice the physical memory.
* This allows for kmem map sparseness, but limits the size
* to something sane. Be careful to not overflow the 32bit
* ints while doing the check.
*/
if (((vm_kmem_size / 2) / PAGE_SIZE) > cnt.v_page_count)
vm_kmem_size = 2 * cnt.v_page_count * PAGE_SIZE;
/*
* Tune settings based on the kmem map's size at this time.
*/
init_param3(vm_kmem_size / PAGE_SIZE);
#ifdef DEBUG_MEMGUARD
tmp = memguard_fudge(vm_kmem_size, vm_kmem_size_max);
#else
tmp = vm_kmem_size;
#endif
kmem_map = kmem_suballoc(kernel_map, &kmembase, &kmemlimit,
tmp, TRUE);
kmem_map->system_map = 1;
#ifdef DEBUG_MEMGUARD
/*
* Initialize MemGuard if support compiled in. MemGuard is a
* replacement allocator used for detecting tamper-after-free
* scenarios as they occur. It is only used for debugging.
*/
memguard_init(kmem_map);
#endif
uma_startup2();
mt_zone = uma_zcreate("mt_zone", sizeof(struct malloc_type_internal),
#ifdef INVARIANTS
mtrash_ctor, mtrash_dtor, mtrash_init, mtrash_fini,
#else
NULL, NULL, NULL, NULL,
#endif
UMA_ALIGN_PTR, UMA_ZONE_MALLOC);
for (i = 0, indx = 0; kmemzones[indx].kz_size != 0; indx++) {
int size = kmemzones[indx].kz_size;
char *name = kmemzones[indx].kz_name;
int subzone;
for (subzone = 0; subzone < numzones; subzone++) {
kmemzones[indx].kz_zone[subzone] =
uma_zcreate(name, size,
#ifdef INVARIANTS
mtrash_ctor, mtrash_dtor, mtrash_init, mtrash_fini,
#else
NULL, NULL, NULL, NULL,
#endif
UMA_ALIGN_PTR, UMA_ZONE_MALLOC);
}
for (;i <= size; i+= KMEM_ZBASE)
kmemsize[i >> KMEM_ZSHIFT] = indx;
}
}
void
malloc_init(void *data)
{
struct malloc_type_internal *mtip;
struct malloc_type *mtp;
KASSERT(cnt.v_page_count != 0, ("malloc_register before vm_init"));
mtp = data;
if (mtp->ks_magic != M_MAGIC)
panic("malloc_init: bad malloc type magic");
mtip = uma_zalloc(mt_zone, M_WAITOK | M_ZERO);
mtp->ks_handle = mtip;
mtip->mti_zone = mtp_get_subzone(mtp->ks_shortdesc);
mtx_lock(&malloc_mtx);
mtp->ks_next = kmemstatistics;
kmemstatistics = mtp;
kmemcount++;
mtx_unlock(&malloc_mtx);
}
void
malloc_uninit(void *data)
{
struct malloc_type_internal *mtip;
struct malloc_type_stats *mtsp;
struct malloc_type *mtp, *temp;
uma_slab_t slab;
long temp_allocs, temp_bytes;
int i;
mtp = data;
KASSERT(mtp->ks_magic == M_MAGIC,
("malloc_uninit: bad malloc type magic"));
KASSERT(mtp->ks_handle != NULL, ("malloc_deregister: cookie NULL"));
mtx_lock(&malloc_mtx);
mtip = mtp->ks_handle;
mtp->ks_handle = NULL;
if (mtp != kmemstatistics) {
for (temp = kmemstatistics; temp != NULL;
temp = temp->ks_next) {
if (temp->ks_next == mtp) {
temp->ks_next = mtp->ks_next;
break;
}
}
KASSERT(temp,
("malloc_uninit: type '%s' not found", mtp->ks_shortdesc));
} else
kmemstatistics = mtp->ks_next;
kmemcount--;
mtx_unlock(&malloc_mtx);
/*
* Look for memory leaks.
*/
temp_allocs = temp_bytes = 0;
for (i = 0; i < MAXCPU; i++) {
mtsp = &mtip->mti_stats[i];
temp_allocs += mtsp->mts_numallocs;
temp_allocs -= mtsp->mts_numfrees;
temp_bytes += mtsp->mts_memalloced;
temp_bytes -= mtsp->mts_memfreed;
}
if (temp_allocs > 0 || temp_bytes > 0) {
printf("Warning: memory type %s leaked memory on destroy "
"(%ld allocations, %ld bytes leaked).\n", mtp->ks_shortdesc,
temp_allocs, temp_bytes);
}
slab = vtoslab((vm_offset_t) mtip & (~UMA_SLAB_MASK));
uma_zfree_arg(mt_zone, mtip, slab);
}
struct malloc_type *
malloc_desc2type(const char *desc)
{
struct malloc_type *mtp;
mtx_assert(&malloc_mtx, MA_OWNED);
for (mtp = kmemstatistics; mtp != NULL; mtp = mtp->ks_next) {
if (strcmp(mtp->ks_shortdesc, desc) == 0)
return (mtp);
}
return (NULL);
}
static int
sysctl_kern_malloc_stats(SYSCTL_HANDLER_ARGS)
{
struct malloc_type_stream_header mtsh;
struct malloc_type_internal *mtip;
struct malloc_type_header mth;
struct malloc_type *mtp;
int buflen, count, error, i;
struct sbuf sbuf;
char *buffer;
mtx_lock(&malloc_mtx);
restart:
mtx_assert(&malloc_mtx, MA_OWNED);
count = kmemcount;
mtx_unlock(&malloc_mtx);
buflen = sizeof(mtsh) + count * (sizeof(mth) +
sizeof(struct malloc_type_stats) * MAXCPU) + 1;
buffer = malloc(buflen, M_TEMP, M_WAITOK | M_ZERO);
mtx_lock(&malloc_mtx);
if (count < kmemcount) {
free(buffer, M_TEMP);
goto restart;
}
sbuf_new(&sbuf, buffer, buflen, SBUF_FIXEDLEN);
/*
* Insert stream header.
*/
bzero(&mtsh, sizeof(mtsh));
mtsh.mtsh_version = MALLOC_TYPE_STREAM_VERSION;
mtsh.mtsh_maxcpus = MAXCPU;
mtsh.mtsh_count = kmemcount;
if (sbuf_bcat(&sbuf, &mtsh, sizeof(mtsh)) < 0) {
mtx_unlock(&malloc_mtx);
error = ENOMEM;
goto out;
}
/*
* Insert alternating sequence of type headers and type statistics.
*/
for (mtp = kmemstatistics; mtp != NULL; mtp = mtp->ks_next) {
mtip = (struct malloc_type_internal *)mtp->ks_handle;
/*
* Insert type header.
*/
bzero(&mth, sizeof(mth));
strlcpy(mth.mth_name, mtp->ks_shortdesc, MALLOC_MAX_NAME);
if (sbuf_bcat(&sbuf, &mth, sizeof(mth)) < 0) {
mtx_unlock(&malloc_mtx);
error = ENOMEM;
goto out;
}
/*
* Insert type statistics for each CPU.
*/
for (i = 0; i < MAXCPU; i++) {
if (sbuf_bcat(&sbuf, &mtip->mti_stats[i],
sizeof(mtip->mti_stats[i])) < 0) {
mtx_unlock(&malloc_mtx);
error = ENOMEM;
goto out;
}
}
}
mtx_unlock(&malloc_mtx);
sbuf_finish(&sbuf);
error = SYSCTL_OUT(req, sbuf_data(&sbuf), sbuf_len(&sbuf));
out:
sbuf_delete(&sbuf);
free(buffer, M_TEMP);
return (error);
}
SYSCTL_PROC(_kern, OID_AUTO, malloc_stats, CTLFLAG_RD|CTLTYPE_STRUCT,
0, 0, sysctl_kern_malloc_stats, "s,malloc_type_ustats",
"Return malloc types");
SYSCTL_INT(_kern, OID_AUTO, malloc_count, CTLFLAG_RD, &kmemcount, 0,
"Count of kernel malloc types");
void
malloc_type_list(malloc_type_list_func_t *func, void *arg)
{
struct malloc_type *mtp, **bufmtp;
int count, i;
size_t buflen;
mtx_lock(&malloc_mtx);
restart:
mtx_assert(&malloc_mtx, MA_OWNED);
count = kmemcount;
mtx_unlock(&malloc_mtx);
buflen = sizeof(struct malloc_type *) * count;
bufmtp = malloc(buflen, M_TEMP, M_WAITOK);
mtx_lock(&malloc_mtx);
if (count < kmemcount) {
free(bufmtp, M_TEMP);
goto restart;
}
for (mtp = kmemstatistics, i = 0; mtp != NULL; mtp = mtp->ks_next, i++)
bufmtp[i] = mtp;
mtx_unlock(&malloc_mtx);
for (i = 0; i < count; i++)
(func)(bufmtp[i], arg);
free(bufmtp, M_TEMP);
}
#ifdef DDB
DB_SHOW_COMMAND(malloc, db_show_malloc)
{
struct malloc_type_internal *mtip;
struct malloc_type *mtp;
uint64_t allocs, frees;
uint64_t alloced, freed;
int i;
db_printf("%18s %12s %12s %12s\n", "Type", "InUse", "MemUse",
"Requests");
for (mtp = kmemstatistics; mtp != NULL; mtp = mtp->ks_next) {
mtip = (struct malloc_type_internal *)mtp->ks_handle;
allocs = 0;
frees = 0;
alloced = 0;
freed = 0;
for (i = 0; i < MAXCPU; i++) {
allocs += mtip->mti_stats[i].mts_numallocs;
frees += mtip->mti_stats[i].mts_numfrees;
alloced += mtip->mti_stats[i].mts_memalloced;
freed += mtip->mti_stats[i].mts_memfreed;
}
db_printf("%18s %12ju %12juK %12ju\n",
mtp->ks_shortdesc, allocs - frees,
(alloced - freed + 1023) / 1024, allocs);
}
}
#if MALLOC_DEBUG_MAXZONES > 1
DB_SHOW_COMMAND(multizone_matches, db_show_multizone_matches)
{
struct malloc_type_internal *mtip;
struct malloc_type *mtp;
u_int subzone;
if (!have_addr) {
db_printf("Usage: show multizone_matches <malloc type/addr>\n");
return;
}
mtp = (void *)addr;
if (mtp->ks_magic != M_MAGIC) {
db_printf("Magic %lx does not match expected %x\n",
mtp->ks_magic, M_MAGIC);
return;
}
mtip = mtp->ks_handle;
subzone = mtip->mti_zone;
for (mtp = kmemstatistics; mtp != NULL; mtp = mtp->ks_next) {
mtip = mtp->ks_handle;
if (mtip->mti_zone != subzone)
continue;
db_printf("%s\n", mtp->ks_shortdesc);
}
}
#endif /* MALLOC_DEBUG_MAXZONES > 1 */
#endif /* DDB */
#ifdef MALLOC_PROFILE
static int
sysctl_kern_mprof(SYSCTL_HANDLER_ARGS)
{
int linesize = 64;
struct sbuf sbuf;
uint64_t count;
uint64_t waste;
uint64_t mem;
int bufsize;
int error;
char *buf;
int rsize;
int size;
int i;
bufsize = linesize * (KMEM_ZSIZE + 1);
bufsize += 128; /* For the stats line */
bufsize += 128; /* For the banner line */
waste = 0;
mem = 0;
buf = malloc(bufsize, M_TEMP, M_WAITOK|M_ZERO);
sbuf_new(&sbuf, buf, bufsize, SBUF_FIXEDLEN);
sbuf_printf(&sbuf,
"\n Size Requests Real Size\n");
for (i = 0; i < KMEM_ZSIZE; i++) {
size = i << KMEM_ZSHIFT;
rsize = kmemzones[kmemsize[i]].kz_size;
count = (long long unsigned)krequests[i];
sbuf_printf(&sbuf, "%6d%28llu%11d\n", size,
(unsigned long long)count, rsize);
if ((rsize * count) > (size * count))
waste += (rsize * count) - (size * count);
mem += (rsize * count);
}
sbuf_printf(&sbuf,
"\nTotal memory used:\t%30llu\nTotal Memory wasted:\t%30llu\n",
(unsigned long long)mem, (unsigned long long)waste);
sbuf_finish(&sbuf);
error = SYSCTL_OUT(req, sbuf_data(&sbuf), sbuf_len(&sbuf));
sbuf_delete(&sbuf);
free(buf, M_TEMP);
return (error);
}
SYSCTL_OID(_kern, OID_AUTO, mprof, CTLTYPE_STRING|CTLFLAG_RD,
NULL, 0, sysctl_kern_mprof, "A", "Malloc Profiling");
#endif /* MALLOC_PROFILE */
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