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Code

bus: properly handle message bodies that are a chain of memory areas rather than a single one

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This commit is contained in:
Lennart Poettering 2013-05-14 22:24:26 +02:00
parent a3dc35472f
commit bc7fd8cdbe
7 changed files with 597 additions and 170 deletions
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4
src/libsystemd-bus/bus-internal.h
View File

@ -33,6 +33,7 @@
#include "sd-bus.h"
#include "bus-error.h"
#include "bus-match.h"
#include "bus-kernel.h"
struct reply_callback {
sd_bus_message_handler_t callback;
@ -152,6 +153,9 @@ struct sd_bus {
unsigned iteration_counter;
void *kdbus_buffer;
struct memfd_cache memfd_cache[MEMFD_CACHE_MAX];
unsigned n_memfd_cache;
};
static inline void bus_unrefp(sd_bus **b) {

120
src/libsystemd-bus/bus-kernel.c
View File

@ -189,6 +189,7 @@ static int bus_message_setup_kmsg(sd_bus *b, sd_bus_message *m) {
uint64_t unique;
size_t sz, dl;
int r;
struct bus_body_part *part;
assert(b);
assert(m);
@ -209,7 +210,8 @@ static int bus_message_setup_kmsg(sd_bus *b, sd_bus_message *m) {
sz = offsetof(struct kdbus_msg, items);
/* Add in fixed header, fields header and payload */
sz += 3 * ALIGN8(offsetof(struct kdbus_item, vec) + sizeof(struct kdbus_vec));
sz += (1 + !!m->fields + m->n_body_parts) *
ALIGN8(offsetof(struct kdbus_item, vec) + sizeof(struct kdbus_vec));
/* Add space for bloom filter */
sz += ALIGN8(offsetof(struct kdbus_item, data) + BLOOM_SIZE);
@ -251,8 +253,8 @@ static int bus_message_setup_kmsg(sd_bus *b, sd_bus_message *m) {
if (m->fields)
append_payload_vec(&d, m->fields, ALIGN8(m->header->fields_size));
if (m->body)
append_payload_vec(&d, m->body, m->header->body_size);
for (part = &m->body; part && part->size > 0; part = part->next)
append_payload_vec(&d, part->data, part->size);
if (m->kdbus->dst_id == KDBUS_DST_ID_BROADCAST) {
void *p;
@ -395,7 +397,10 @@ static void close_kdbus_msg(sd_bus *bus, struct kdbus_msg *k) {
}
}
static bool range_contains(size_t astart, size_t asize, size_t bstart, size_t bsize, void *a, void **b) {
static bool range_contains(
size_t astart, size_t asize,
size_t bstart, size_t bsize,
void *a, void **b) {
if (bstart < astart)
return false;
@ -484,11 +489,35 @@ static int bus_kernel_make_message(sd_bus *bus, struct kdbus_msg *k, sd_bus_mess
l = d->size - offsetof(struct kdbus_item, data);
if (d->type == KDBUS_MSG_PAYLOAD_VEC) {
size_t begin_body;
/* Fill in fields material */
range_contains(idx, d->vec.size, ALIGN8(sizeof(struct bus_header)), BUS_MESSAGE_FIELDS_SIZE(m),
UINT64_TO_PTR(d->vec.address), &m->fields);
range_contains(idx, d->vec.size, ALIGN8(sizeof(struct bus_header)) + ALIGN8(BUS_MESSAGE_FIELDS_SIZE(m)),
BUS_MESSAGE_BODY_SIZE(m), UINT64_TO_PTR(d->vec.address), &m->body);
begin_body = ALIGN8(sizeof(struct bus_header)) + ALIGN8(BUS_MESSAGE_FIELDS_SIZE(m));
if (idx + d->vec.size > begin_body) {
struct bus_body_part *part;
/* Contains body material */
part = message_append_part(m);
if (!part) {
sd_bus_message_unref(m);
return -ENOMEM;
}
if (idx >= begin_body) {
part->data = (void*) d->vec.address;
part->size = d->vec.size;
} else {
part->data = (uint8_t*) (uintptr_t) d->vec.address + (begin_body - idx);
part->size = d->vec.size - (begin_body - idx);
}
part->sealed = true;
}
idx += d->vec.size;
@ -524,8 +553,7 @@ static int bus_kernel_make_message(sd_bus *bus, struct kdbus_msg *k, sd_bus_mess
log_debug("Got unknown field from kernel %llu", d->type);
}
if ((BUS_MESSAGE_FIELDS_SIZE(m) > 0 && !m->fields) ||
(BUS_MESSAGE_BODY_SIZE(m) > 0 && !m->body)) {
if ((BUS_MESSAGE_FIELDS_SIZE(m) > 0 && !m->fields) || BUS_MESSAGE_SIZE(m) != idx) {
sd_bus_message_unref(m);
return -EBADMSG;
}
@ -646,3 +674,79 @@ int bus_kernel_create(const char *name, char **s) {
return fd;
}
int bus_kernel_pop_memfd(sd_bus *bus, void **address, size_t *size) {
struct memfd_cache *c;
assert(address);
assert(size);
if (!bus || !bus->is_kernel)
return -ENOTSUP;
if (bus->n_memfd_cache <= 0) {
int fd;
fd = ioctl(bus->input_fd, KDBUS_CMD_MEMFD_NEW, &fd);
if (fd < 0)
return -errno;
*address = NULL;
*size = 0;
return fd;
}
c = &bus->memfd_cache[-- bus->n_memfd_cache];
assert(c->fd >= 0);
assert(c->size == 0 || c->address);
*address = c->address;
*size = c->size;
return c->fd;
}
void bus_kernel_push_memfd(sd_bus *bus, int fd, void *address, size_t size) {
struct memfd_cache *c;
assert(fd >= 0);
assert(size == 0 || address);
if (!bus || !bus->is_kernel ||
bus->n_memfd_cache >= ELEMENTSOF(bus->memfd_cache)) {
if (size > 0)
assert_se(munmap(address, PAGE_ALIGN(size)) == 0);
close_nointr_nofail(fd);
return;
}
c = &bus->memfd_cache[bus->n_memfd_cache++];
c->fd = fd;
c->address = address;
/* If overly long, let's return a bit to the OS */
if (size > MEMFD_CACHE_ITEM_SIZE_MAX) {
uint64_t sz = MEMFD_CACHE_ITEM_SIZE_MAX;
ioctl(bus->input_fd, KDBUS_CMD_MEMFD_SIZE_SET, &sz);
c->size = MEMFD_CACHE_ITEM_SIZE_MAX;
} else
c->size = size;
}
void bus_kernel_flush_memfd(sd_bus *b) {
unsigned i;
assert(b);
for (i = 0; i < b->n_memfd_cache; i++) {
if (b->memfd_cache[i].size > 0)
assert_se(munmap(b->memfd_cache[i].address, PAGE_ALIGN(b->memfd_cache[i].size)) == 0);
close_nointr_nofail(b->memfd_cache[i].fd);
}
}

14
src/libsystemd-bus/bus-kernel.h
View File

@ -23,6 +23,15 @@
#include "sd-bus.h"
#define MEMFD_CACHE_MAX 32
#define MEMFD_CACHE_ITEM_SIZE_MAX (128*1024)
struct memfd_cache {
int fd;
void *address;
size_t size;
};
int bus_kernel_connect(sd_bus *b);
int bus_kernel_take_fd(sd_bus *b);
@ -30,3 +39,8 @@ int bus_kernel_write_message(sd_bus *bus, sd_bus_message *m);
int bus_kernel_read_message(sd_bus *bus, sd_bus_message **m);
int bus_kernel_create(const char *name, char **s);
int bus_kernel_pop_memfd(sd_bus *bus, void **address, size_t *size);
void bus_kernel_push_memfd(sd_bus *bus, int fd, void *address, size_t size);
void bus_kernel_flush_memfd(sd_bus *bus);

550
src/libsystemd-bus/bus-message.c
View File

@ -21,6 +21,7 @@
#include <errno.h>
#include <fcntl.h>
#include <sys/mman.h>
#include "util.h"
#include "utf8.h"
@ -36,7 +37,65 @@
static int message_append_basic(sd_bus_message *m, char type, const void *p, const void **stored);
static void reset_containers(sd_bus_message *m) {
static void *adjust_pointer(const void *p, void *old_base, size_t sz, void *new_base) {
if (p == NULL)
return NULL;
if (old_base == new_base)
return (void*) p;
if ((uint8_t*) p < (uint8_t*) old_base)
return (void*) p;
if ((uint8_t*) p >= (uint8_t*) old_base + sz)
return (void*) p;
return (uint8_t*) new_base + ((uint8_t*) p - (uint8_t*) old_base);
}
static void message_free_part(sd_bus_message *m, struct bus_body_part *part) {
assert(m);
assert(part);
if (part->memfd >= 0) {
if (!part->sealed)
bus_kernel_push_memfd(m->bus, part->memfd, part->data, part->mapped);
else {
if (part->size > 0)
assert_se(munmap(part->data, PAGE_ALIGN(part->size)) == 0);
close_nointr_nofail(part->memfd);
}
} else if (part->free_this)
free(part->data);
if (part != &m->body)
free(part);
}
static void message_reset_parts(sd_bus_message *m) {
struct bus_body_part *part;
assert(m);
part = &m->body;
while (m->n_body_parts > 0) {
struct bus_body_part *next = part->next;
message_free_part(m, part);
part = next;
m->n_body_parts--;
}
m->body_end = NULL;
m->cached_rindex_part = NULL;
m->cached_rindex_part_begin = 0;
}
static void message_reset_containers(sd_bus_message *m) {
unsigned i;
assert(m);
@ -60,8 +119,7 @@ static void message_free(sd_bus_message *m) {
if (m->free_fields)
free(m->fields);
if (m->free_body)
free(m->body);
message_reset_parts(m);
if (m->free_kdbus)
free(m->kdbus);
@ -77,9 +135,12 @@ static void message_free(sd_bus_message *m) {
if (m->bus)
sd_bus_unref(m->bus);
if (m->iovec != m->iovec_fixed)
free(m->iovec);
free(m->cmdline_array);
reset_containers(m);
message_reset_containers(m);
free(m->root_container.signature);
free(m->peeked_signature);
@ -91,7 +152,7 @@ static void message_free(sd_bus_message *m) {
}
static void* buffer_extend(void **p, uint32_t *sz, size_t align, size_t extend) {
size_t start, n;
size_t start, end;
void *k;
assert(p);
@ -99,15 +160,15 @@ static void* buffer_extend(void **p, uint32_t *sz, size_t align, size_t extend)
assert(align > 0);
start = ALIGN_TO((size_t) *sz, align);
n = start + extend;
end = start + extend;
if (n == *sz)
if (end == *sz)
return (uint8_t*) *p + start;
if (n > (size_t) ((uint32_t) -1))
if (end > (size_t) ((uint32_t) -1))
return NULL;
k = realloc(*p, n);
k = realloc(*p, end);
if (!k)
return NULL;
@ -116,38 +177,37 @@ static void* buffer_extend(void **p, uint32_t *sz, size_t align, size_t extend)
memset((uint8_t*) k + *sz, 0, start - *sz);
*p = k;
*sz = n;
*sz = end;
return (uint8_t*) k + start;
}
static void *message_extend_fields(sd_bus_message *m, size_t align, size_t sz) {
void *p, *o;
void *p, *op;
size_t os;
assert(m);
o = m->fields;
p = buffer_extend(&m->fields, &m->header->fields_size, align, sz);
if (!p)
if (m->poisoned)
return NULL;
if (o != m->fields) {
/* Adjust quick access pointers */
op = m->fields;
os = m->header->fields_size;
if (m->path)
m->path = (const char*) m->fields + (m->path - (const char*) o);
if (m->interface)
m->interface = (const char*) m->fields + (m->interface - (const char*) o);
if (m->member)
m->member = (const char*) m->fields + (m->member - (const char*) o);
if (m->destination)
m->destination = (const char*) m->fields + (m->destination - (const char*) o);
if (m->sender)
m->sender = (const char*) m->fields + (m->sender - (const char*) o);
if (m->error.name)
m->error.name = (const char*) m->fields + (m->error.name - (const char*) o);
p = buffer_extend(&m->fields, &m->header->fields_size, align, sz);
if (!p) {
m->poisoned = true;
return NULL;
}
/* Adjust quick access pointers */
m->path = adjust_pointer(m->path, op, os, m->fields);
m->interface = adjust_pointer(m->interface, op, os, m->fields);
m->member = adjust_pointer(m->member, op, os, m->fields);
m->destination = adjust_pointer(m->destination, op, os, m->fields);
m->sender = adjust_pointer(m->sender, op, os, m->fields);
m->error.name = adjust_pointer(m->error.name, op, os, m->fields);
m->free_fields = true;
return p;
@ -183,7 +243,7 @@ static int message_append_field_string(
memcpy(p + 8, s, l + 1);
if (ret)
*ret = (const char*) p + 8;
*ret = (char*) p + 8;
return 0;
}
@ -331,9 +391,15 @@ int bus_message_from_malloc(
}
m->fields = (uint8_t*) buffer + sizeof(struct bus_header);
m->body = (uint8_t*) buffer + sizeof(struct bus_header) + ALIGN8(BUS_MESSAGE_FIELDS_SIZE(m));
m->n_body_parts = 1;
m->body.data = (uint8_t*) buffer + sizeof(struct bus_header) + ALIGN8(BUS_MESSAGE_FIELDS_SIZE(m));
m->body.size = length - sizeof(struct bus_header) - ALIGN8(BUS_MESSAGE_FIELDS_SIZE(m));
m->body.sealed = true;
m->body.memfd = -1;
m->n_iovec = 1;
m->iovec = m->iovec_fixed;
m->iovec[0].iov_base = buffer;
m->iovec[0].iov_len = length;
@ -1022,35 +1088,188 @@ static struct bus_container *message_get_container(sd_bus_message *m) {
return m->containers + m->n_containers - 1;
}
struct bus_body_part *message_append_part(sd_bus_message *m) {
struct bus_body_part *part;
assert(m);
if (m->poisoned)
return NULL;
if (m->n_body_parts <= 0) {
part = &m->body;
zero(*part);
} else {
assert(m->body_end);
part = new0(struct bus_body_part, 1);
if (!part) {
m->poisoned = true;
return NULL;
}
m->body_end->next = part;
}
part->memfd = -1;
m->body_end = part;
m->n_body_parts ++;
return part;
}
static void part_zero(struct bus_body_part *part, size_t sz) {
assert(part);
assert(sz > 0);
assert(sz < 8);
part->data = NULL;
part->size = sz;
}
static int part_make_space(
struct sd_bus_message *m,
struct bus_body_part *part,
size_t sz,
void **q) {
void *n;
int r;
assert(m);
assert(part);
assert(!part->sealed);
if (m->poisoned)
return -ENOMEM;
if (!part->data && part->memfd < 0)
part->memfd = bus_kernel_pop_memfd(m->bus, &part->data, &part->mapped);
if (part->memfd >= 0) {
uint64_t u = sz;
r = ioctl(part->memfd, KDBUS_CMD_MEMFD_SIZE_SET, &u);
if (r < 0) {
m->poisoned = true;
return -errno;
}
if (sz > part->mapped) {
size_t psz = PAGE_ALIGN(sz);
if (part->mapped <= 0)
n = mmap(NULL, psz, PROT_READ|PROT_WRITE, MAP_SHARED, part->memfd, 0);
else
n = mremap(part->data, part->mapped, psz, MREMAP_MAYMOVE);
if (n == MAP_FAILED) {
m->poisoned = true;
return -errno;
}
part->mapped = psz;
part->data = n;
}
} else {
n = realloc(part->data, sz);
if (!n) {
m->poisoned = true;
return -ENOMEM;
}
part->data = n;
part->free_this = true;
}
if (q)
*q = part->data ? (uint8_t*) part->data + part->size : NULL;
part->size = sz;
return 0;
}
static void *message_extend_body(sd_bus_message *m, size_t align, size_t sz) {
void *p, *o;
size_t added;
struct bus_container *c;
struct bus_body_part *part = NULL;
size_t start_body, end_body, padding, start_part, end_part, added;
bool add_new_part;
void *p;
int r;
assert(m);
assert(align > 0);
assert(!m->sealed);
o = m->body;
added = m->header->body_size;
p = buffer_extend(&m->body, &m->header->body_size, align, sz);
if (!p)
if (m->poisoned)
return NULL;
added = m->header->body_size - added;
start_body = ALIGN_TO((size_t) m->header->body_size, align);
end_body = start_body + sz;
padding = start_body - m->header->body_size;
added = padding + sz;
/* Check for 32bit overflows */
if (end_body > (size_t) ((uint32_t) -1)) {
m->poisoned = true;
return NULL;
}
add_new_part =
m->n_body_parts <= 0 ||
m->body_end->sealed ||
padding != ALIGN_TO(m->body_end->size, align) - m->body_end->size;
if (add_new_part) {
if (padding > 0) {
part = message_append_part(m);
if (!part)
return NULL;
part_zero(part, padding);
}
part = message_append_part(m);
if (!part)
return NULL;
r = part_make_space(m, part, sz, &p);
if (r < 0)
return NULL;
} else {
void *op;
size_t os;
part = m->body_end;
op = part->data;
os = part->size;
start_part = ALIGN_TO(part->size, align);
end_part = start_part + sz;
r = part_make_space(m, part, end_part, &p);
if (r < 0)
return NULL;
if (padding > 0) {
memset(p, 0, padding);
p = (uint8_t*) p + padding;
}
/* Readjust pointers */
for (c = m->containers; c < m->containers + m->n_containers; c++)
if (c->array_size) {
c->array_size = (uint32_t*) ((uint8_t*) m->body + ((uint8_t*) c->array_size - (uint8_t*) o));
c->array_size = adjust_pointer(c->array_size, op, os, part->data);
m->error.message = (const char*) adjust_pointer(m->error.message, op, os, part->data);
}
/* Update counters */
for (c = m->containers; c < m->containers + m->n_containers; c++)
if (c->array_size)
*c->array_size += added;
}
if (o != m->body) {
if (m->error.message)
m->error.message = (const char*) m->body + (m->error.message - (const char*) o);
}
m->free_body = true;
m->header->body_size = end_body;
return p;
}
@ -1073,6 +1292,8 @@ int message_append_basic(sd_bus_message *m, char type, const void *p, const void
return -EPERM;
if (!bus_type_is_basic(type))
return -EINVAL;
if (m->poisoned)
return -ESTALE;
c = message_get_container(m);
@ -1087,9 +1308,11 @@ int message_append_basic(sd_bus_message *m, char type, const void *p, const void
return -ENXIO;
e = strextend(&c->signature, CHAR_TO_STR(type), NULL);
if (!e)
if (!e) {
m->poisoned = true;
return -ENOMEM;
}
}
switch (type) {
@ -1139,6 +1362,7 @@ int message_append_basic(sd_bus_message *m, char type, const void *p, const void
f = realloc(m->fds, sizeof(int) * (m->n_fds + 1));
if (!f) {
m->poisoned = true;
r = -ENOMEM;
goto fail;
}
@ -1199,10 +1423,6 @@ int message_append_basic(sd_bus_message *m, char type, const void *p, const void
return 0;
fail:
/* Truncate extended signature again */
if (e)
c->signature[c->index] = 0;
if (fd >= 0)
close_nointr_nofail(fd);
@ -1217,7 +1437,6 @@ int sd_bus_message_append_string_space(sd_bus_message *m, size_t size, char **s)
struct bus_container *c;
char *e;
void *a;
int r;
if (!m)
return -EINVAL;
@ -1225,6 +1444,8 @@ int sd_bus_message_append_string_space(sd_bus_message *m, size_t size, char **s)
return -EINVAL;
if (m->sealed)
return -EPERM;
if (m->poisoned)
return -ESTALE;
c = message_get_container(m);
@ -1239,16 +1460,16 @@ int sd_bus_message_append_string_space(sd_bus_message *m, size_t size, char **s)
return -ENXIO;
e = strextend(&c->signature, CHAR_TO_STR(SD_BUS_TYPE_STRING), NULL);
if (!e)
if (!e) {
m->poisoned = true;
return -ENOMEM;
}
}
a = message_extend_body(m, 4, 4 + size + 1);
if (!a) {
r = -ENOMEM;
goto fail;
}
if (!a)
return -ENOMEM;
*(uint32_t*) a = size;
*s = (char*) a + 4;
@ -1259,12 +1480,6 @@ int sd_bus_message_append_string_space(sd_bus_message *m, size_t size, char **s)
c->index++;
return 0;
fail:
if (e)
c->signature[c->index] = 0;
return r;
}
static int bus_message_open_array(
@ -1275,9 +1490,10 @@ static int bus_message_open_array(
unsigned nindex;
char *e = NULL;
void *a, *b;
void *a, *op;
int alignment;
size_t saved;
size_t os;
struct bus_body_part *o;
assert(m);
assert(c);
@ -1309,39 +1525,34 @@ static int bus_message_open_array(
/* Extend the existing signature */
e = strextend(&c->signature, CHAR_TO_STR(SD_BUS_TYPE_ARRAY), contents, NULL);
if (!e)
if (!e) {
m->poisoned = true;
return -ENOMEM;
}
nindex = e - c->signature;
}
saved = m->header->body_size;
a = message_extend_body(m, 4, 4);
if (!a) {
/* Truncate extended signature again */
if (e)
c->signature[c->index] = 0;
if (!a)
return -ENOMEM;
}
b = m->body;
if (!message_extend_body(m, alignment, 0)) {
o = m->body_end;
op = m->body_end->data;
os = m->body_end->size;
/* Add alignment between size and first element */
if (e)
c->signature[c->index] = 0;
m->header->body_size = saved;
if (!message_extend_body(m, alignment, 0))
return -ENOMEM;
}
if (c->enclosing != SD_BUS_TYPE_ARRAY)
c->index = nindex;
/* m->body might have changed so let's readjust a */
a = (uint8_t*) m->body + ((uint8_t*) a - (uint8_t*) b);
*(uint32_t*) a = 0;
/* location of array size might have changed so let's readjust a */
if (o == m->body_end)
a = adjust_pointer(a, op, os, m->body_end->data);
*(uint32_t*) a = 0;
*array_size = a;
return 0;
}
@ -1375,19 +1586,16 @@ static int bus_message_open_variant(
return -ENXIO;
e = strextend(&c->signature, CHAR_TO_STR(SD_BUS_TYPE_VARIANT), NULL);
if (!e)
if (!e) {
m->poisoned = true;
return -ENOMEM;
}
}
l = strlen(contents);
a = message_extend_body(m, 1, 1 + l + 1);
if (!a) {
/* Truncate extended signature again */
if (e)
c->signature[c->index] = 0;
if (!a)
return -ENOMEM;
}
*(uint8_t*) a = l;
memcpy((uint8_t*) a + 1, contents, l + 1);
@ -1429,19 +1637,17 @@ static int bus_message_open_struct(
return -ENXIO;
e = strextend(&c->signature, CHAR_TO_STR(SD_BUS_TYPE_STRUCT_BEGIN), contents, CHAR_TO_STR(SD_BUS_TYPE_STRUCT_END), NULL);
if (!e)
if (!e) {
m->poisoned = true;
return -ENOMEM;
}
nindex = e - c->signature;
}
/* Align contents to 8 byte boundary */
if (!message_extend_body(m, 8, 0)) {
if (e)
c->signature[c->index] = 0;
if (!message_extend_body(m, 8, 0))
return -ENOMEM;
}
if (c->enclosing != SD_BUS_TYPE_ARRAY)
c->index = nindex;
@ -1507,18 +1713,25 @@ int sd_bus_message_open_container(
return -EPERM;
if (!contents)
return -EINVAL;
if (m->poisoned)
return -ESTALE;
/* Make sure we have space for one more container */
w = realloc(m->containers, sizeof(struct bus_container) * (m->n_containers + 1));
if (!w)
if (!w) {
m->poisoned = true;
return -ENOMEM;
}
m->containers = w;
c = message_get_container(m);
signature = strdup(contents);
if (!signature)
if (!signature) {
m->poisoned = true;
return -ENOMEM;
}
/* Save old index in the parent container, in case we have to
* abort this container */
@ -1562,6 +1775,8 @@ int sd_bus_message_close_container(sd_bus_message *m) {
return -EPERM;
if (m->n_containers <= 0)
return -EINVAL;
if (m->poisoned)
return -ESTALE;
c = message_get_container(m);
if (c->enclosing != SD_BUS_TYPE_ARRAY)
@ -1574,37 +1789,6 @@ int sd_bus_message_close_container(sd_bus_message *m) {
return 0;
}
static void message_abort_container(sd_bus_message *m) {
struct bus_container *c;
size_t delta;
assert(m);
assert(!m->sealed);
assert(m->n_containers > 0);
c = message_get_container(m);
/* Undo appends */
assert(m->header->body_size >= c->before);
delta = m->header->body_size - c->before;
m->header->body_size = c->before;
/* Free container */
free(c->signature);
m->n_containers--;
/* Correct index of new top-level container */
c = message_get_container(m);
c->index = c->saved_index;
/* Correct array sizes all the way up */
for (c = m->containers; c < m->containers + m->n_containers; c++)
if (c->array_size) {
assert(*c->array_size >= delta);
*c->array_size -= delta;
}
}
typedef struct {
const char *types;
unsigned n_struct;
@ -1849,6 +2033,8 @@ int sd_bus_message_append(sd_bus_message *m, const char *types, ...) {
return -EINVAL;
if (m->sealed)
return -EPERM;
if (m->poisoned)
return -ESTALE;
if (!types)
return 0;
@ -1872,6 +2058,8 @@ int sd_bus_message_append_array_space(sd_bus_message *m, char type, size_t size,
return -EINVAL;
if (!ptr && size > 0)
return -EINVAL;
if (m->poisoned)
return -ESTALE;
align = bus_type_get_alignment(type);
sz = bus_type_get_size(type);
@ -1887,21 +2075,15 @@ int sd_bus_message_append_array_space(sd_bus_message *m, char type, size_t size,
return r;
a = message_extend_body(m, align, size);
if (!a) {
r = -ENOMEM;
goto fail;
}
if (!a)
return -ENOMEM;
r = sd_bus_message_close_container(m);
if (r < 0)
goto fail;
return r;
*ptr = a;
return 0;
fail:
message_abort_container(m);
return r;
}
int sd_bus_message_append_array(sd_bus_message *m, char type, const void *ptr, size_t size) {
@ -1922,15 +2104,15 @@ int sd_bus_message_append_array(sd_bus_message *m, char type, const void *ptr, s
}
static int buffer_peek(const void *p, uint32_t sz, size_t *rindex, size_t align, size_t nbytes, void **r) {
size_t k, start, n;
size_t k, start, end;
assert(rindex);
assert(align > 0);
start = ALIGN_TO((size_t) *rindex, align);
n = start + nbytes;
end = start + nbytes;
if (n > sz)
if (end > sz)
return -EBADMSG;
/* Verify that padding is 0 */
@ -1941,7 +2123,7 @@ static int buffer_peek(const void *p, uint32_t sz, size_t *rindex, size_t align,
if (r)
*r = (uint8_t*) p + start;
*rindex = n;
*rindex = end;
return 1;
}
@ -1958,7 +2140,50 @@ static bool message_end_of_array(sd_bus_message *m, size_t index) {
return index >= c->begin + BUS_MESSAGE_BSWAP32(m, *c->array_size);
}
static int message_peek_body(sd_bus_message *m, size_t *rindex, size_t align, size_t nbytes, void **ret) {
static struct bus_body_part* find_part(sd_bus_message *m, size_t index, size_t sz, void **p) {
struct bus_body_part *part;
size_t begin;
assert(m);
if (m->cached_rindex_part && index >= m->cached_rindex_part_begin) {
part = m->cached_rindex_part;
begin = m->cached_rindex_part_begin;
} else {
part = &m->body;
begin = 0;
}
while (part) {
if (index < begin)
return NULL;
if (index + sz <= begin + part->size) {
if (p)
*p = part->data ? (uint8_t*) part->data + index - begin : NULL;
m->cached_rindex_part = part;
m->cached_rindex_part_begin = begin;
return part;
}
part = part->next;
}
return NULL;
}
static int message_peek_body(
sd_bus_message *m,
size_t *rindex,
size_t align,
size_t nbytes,
void **ret) {
size_t k, start, end, padding;
struct bus_body_part *part;
uint8_t *q;
assert(m);
assert(rindex);
assert(align > 0);
@ -1966,7 +2191,34 @@ static int message_peek_body(sd_bus_message *m, size_t *rindex, size_t align, si
if (message_end_of_array(m, *rindex))
return 0;
return buffer_peek(m->body, BUS_MESSAGE_BODY_SIZE(m), rindex, align, nbytes, ret);
start = ALIGN_TO((size_t) *rindex, align);
padding = start - *rindex;
end = start + nbytes;
if (end > BUS_MESSAGE_BODY_SIZE(m))
return -EBADMSG;
part = find_part(m, *rindex, padding, (void**) &q);
if (!part)
return -EBADMSG;
if (q) {
/* Verify padding */
for (k = 0; k < padding; k++)
if (q[k] != 0)
return -EBADMSG;
}
part = find_part(m, start, nbytes, (void**) &q);
if (!part || !q)
return -EBADMSG;
*rindex = end;
if (ret)
*ret = q;
return 1;
}
static bool validate_nul(const char *s, size_t l) {
@ -2601,7 +2853,7 @@ int sd_bus_message_rewind(sd_bus_message *m, int complete) {
return -EPERM;
if (complete) {
reset_containers(m);
message_reset_containers(m);
m->rindex = 0;
m->root_container.index = 0;
@ -3620,6 +3872,8 @@ int bus_message_dump(sd_bus_message *m) {
int bus_message_get_blob(sd_bus_message *m, void **buffer, size_t *sz) {
size_t total;
void *p, *e;
unsigned i;
struct bus_body_part *part;
assert(m);
assert(buffer);
@ -3640,8 +3894,8 @@ int bus_message_get_blob(sd_bus_message *m, void **buffer, size_t *sz) {
e = mempset(e, 0, 8 - (m->header->fields_size % 8));
}
if (m->body)
e = mempcpy(e, m->body, m->header->body_size);
for (i = 0, part = &m->body; i < m->n_body_parts; i++, part = part->next)
e = mempcpy(e, part->data, part->size);
assert(total == (size_t) ((uint8_t*) e - (uint8_t*) p));

26
src/libsystemd-bus/bus-message.h
View File

@ -50,6 +50,16 @@ struct bus_header {
uint32_t fields_size;
} _packed_;
struct bus_body_part {
void *data;
size_t size;
size_t mapped;
int memfd;
bool free_this:1;
bool sealed:1;
struct bus_body_part *next;
};
struct sd_bus_message {
unsigned n_ref;
@ -80,19 +90,22 @@ struct sd_bus_message {
bool gid_valid:1;
bool free_header:1;
bool free_fields:1;
bool free_body:1;
bool free_kdbus:1;
bool free_fds:1;
bool release_kdbus:1;
bool poisoned:1;
struct bus_header *header;
void *fields;
void *body;
struct kdbus_msg *kdbus;
struct bus_body_part body;
struct bus_body_part *body_end;
unsigned n_body_parts;
char *label;
size_t rindex;
struct bus_body_part *cached_rindex_part;
size_t cached_rindex_part_begin;
uint32_t n_fds;
int *fds;
@ -100,9 +113,12 @@ struct sd_bus_message {
struct bus_container root_container, *containers;
unsigned n_containers;
struct iovec iovec[3];
struct iovec *iovec;
struct iovec iovec_fixed[3];
unsigned n_iovec;
struct kdbus_msg *kdbus;
char *peeked_signature;
usec_t timeout;
@ -199,3 +215,5 @@ int bus_message_append_ap(sd_bus_message *m, const char *types, va_list ap);
int bus_message_parse_fields(sd_bus_message *m);
int bus_header_size(struct bus_header *h, size_t *sum);
struct bus_body_part *message_append_part(sd_bus_message *m);

50
src/libsystemd-bus/bus-socket.c
View File

@ -58,7 +58,7 @@ static void iovec_advance(struct iovec iov[], unsigned *idx, size_t size) {
}
}
static void append_iovec(sd_bus_message *m, const void *p, size_t sz) {
static int append_iovec(sd_bus_message *m, const void *p, size_t sz) {
assert(m);
assert(p);
assert(sz > 0);
@ -66,22 +66,51 @@ static void append_iovec(sd_bus_message *m, const void *p, size_t sz) {
m->iovec[m->n_iovec].iov_base = (void*) p;
m->iovec[m->n_iovec].iov_len = sz;
m->n_iovec++;
return 0;
}
static void bus_message_setup_iovec(sd_bus_message *m) {
static int bus_message_setup_iovec(sd_bus_message *m) {
struct bus_body_part *part;
unsigned n;
int r;
assert(m);
assert(m->sealed);
if (m->n_iovec > 0)
return;
return 0;
append_iovec(m, m->header, sizeof(*m->header));
assert(!m->iovec);
if (m->fields)
append_iovec(m, m->fields, ALIGN8(m->header->fields_size));
n = 1 + !!m->fields + m->n_body_parts;
if (n < ELEMENTSOF(m->iovec_fixed))
m->iovec = m->iovec_fixed;
else {
m->iovec = new(struct iovec, n);
if (!m->iovec)
return -ENOMEM;
}
if (m->body)
append_iovec(m, m->body, m->header->body_size);
r = append_iovec(m, m->header, sizeof(*m->header));
if (r < 0)
return r;
if (m->fields) {
r = append_iovec(m, m->fields, ALIGN8(m->header->fields_size));
if (r < 0)
return r;
}
for (part = &m->body; part && part->size > 0; part = part->next) {
r = append_iovec(m, part->data, part->size);
if (r < 0)
return r;
}
assert(n == m->n_iovec);
return 0;
}
bool bus_socket_auth_needs_write(sd_bus *b) {
@ -749,6 +778,7 @@ int bus_socket_write_message(sd_bus *bus, sd_bus_message *m, size_t *idx) {
ssize_t k;
size_t n;
unsigned j;
int r;
assert(bus);
assert(m);
@ -758,7 +788,9 @@ int bus_socket_write_message(sd_bus *bus, sd_bus_message *m, size_t *idx) {
if (*idx >= BUS_MESSAGE_SIZE(m))
return 0;
bus_message_setup_iovec(m);
r = bus_message_setup_iovec(m);
if (r < 0)
return r;
n = m->n_iovec * sizeof(struct iovec);
iov = alloca(n);

3
src/libsystemd-bus/sd-bus.c
View File

@ -86,9 +86,10 @@ static void bus_free(sd_bus *b) {
}
hashmap_free(b->object_callbacks);
bus_match_free(&b->match_callbacks);
bus_kernel_flush_memfd(b);
free(b);
}