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nbd/server: Favor [u]int64_t over off_t

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Although our compile-time environment is set up so that we always
support long files with 64-bit off_t, we have no guarantee whether
off_t is the same type as int64_t.  This requires casts when
printing values, and prevents us from directly using qemu_strtoi64()
(which will be done in the next patch). Let's just flip to uint64_t
where possible, and stick to int64_t for detecting failure of
blk_getlength(); we also keep the assertions added in the previous
patch that the resulting values fit in 63 bits.  The overflow check
in nbd_co_receive_request() was already sane (request->from is
validated to fit in 63 bits, and request->len is 32 bits, so the
addition can't overflow 64 bits), but rewrite it in a form easier
to recognize as a typical overflow check.

Rename the variable 'description' to keep line lengths reasonable.

Suggested-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20190117193658.16413-7-eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
This commit is contained in:
Eric Blake 2019-01-17 13:36:43 -06:00
parent 7596bbb390
commit 9d26dfcbab
3 changed files with 22 additions and 29 deletions
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4
include/block/nbd.h
View File

@ -294,8 +294,8 @@ int nbd_errno_to_system_errno(int err);
typedef struct NBDExport NBDExport; typedef struct NBDExport NBDExport;
typedef struct NBDClient NBDClient; typedef struct NBDClient NBDClient;
NBDExport *nbd_export_new(BlockDriverState *bs, off_t dev_offset, off_t size, NBDExport *nbd_export_new(BlockDriverState *bs, uint64_t dev_offset,
const char *name, const char *description, uint64_t size, const char *name, const char *desc,
const char *bitmap, uint16_t nbdflags, const char *bitmap, uint16_t nbdflags,
void (*close)(NBDExport *), bool writethrough, void (*close)(NBDExport *), bool writethrough,
BlockBackend *on_eject_blk, Error **errp); BlockBackend *on_eject_blk, Error **errp);

18
nbd/server.c
View File

@ -77,8 +77,8 @@ struct NBDExport {
BlockBackend *blk; BlockBackend *blk;
char *name; char *name;
char *description; char *description;
off_t dev_offset; uint64_t dev_offset;
off_t size; uint64_t size;
uint16_t nbdflags; uint16_t nbdflags;
QTAILQ_HEAD(, NBDClient) clients; QTAILQ_HEAD(, NBDClient) clients;
QTAILQ_ENTRY(NBDExport) next; QTAILQ_ENTRY(NBDExport) next;
@ -1455,8 +1455,8 @@ static void nbd_eject_notifier(Notifier *n, void *data)
nbd_export_close(exp); nbd_export_close(exp);
} }
NBDExport *nbd_export_new(BlockDriverState *bs, off_t dev_offset, off_t size, NBDExport *nbd_export_new(BlockDriverState *bs, uint64_t dev_offset,
const char *name, const char *description, uint64_t size, const char *name, const char *desc,
const char *bitmap, uint16_t nbdflags, const char *bitmap, uint16_t nbdflags,
void (*close)(NBDExport *), bool writethrough, void (*close)(NBDExport *), bool writethrough,
BlockBackend *on_eject_blk, Error **errp) BlockBackend *on_eject_blk, Error **errp)
@ -1495,12 +1495,12 @@ NBDExport *nbd_export_new(BlockDriverState *bs, off_t dev_offset, off_t size,
exp->refcount = 1; exp->refcount = 1;
QTAILQ_INIT(&exp->clients); QTAILQ_INIT(&exp->clients);
exp->blk = blk; exp->blk = blk;
assert(dev_offset >= 0 && dev_offset <= INT64_MAX); assert(dev_offset <= INT64_MAX);
exp->dev_offset = dev_offset; exp->dev_offset = dev_offset;
exp->name = g_strdup(name); exp->name = g_strdup(name);
exp->description = g_strdup(description); exp->description = g_strdup(desc);
exp->nbdflags = nbdflags; exp->nbdflags = nbdflags;
assert(size >= 0 && size <= INT64_MAX - dev_offset); assert(size <= INT64_MAX - dev_offset);
exp->size = QEMU_ALIGN_DOWN(size, BDRV_SECTOR_SIZE); exp->size = QEMU_ALIGN_DOWN(size, BDRV_SECTOR_SIZE);
if (bitmap) { if (bitmap) {
@ -2130,10 +2130,10 @@ static int nbd_co_receive_request(NBDRequestData *req, NBDRequest *request,
return -EROFS; return -EROFS;
} }
if (request->from > client->exp->size || if (request->from > client->exp->size ||
request->from + request->len > client->exp->size) { request->len > client->exp->size - request->from) {
error_setg(errp, "operation past EOF; From: %" PRIu64 ", Len: %" PRIu32 error_setg(errp, "operation past EOF; From: %" PRIu64 ", Len: %" PRIu32
", Size: %" PRIu64, request->from, request->len, ", Size: %" PRIu64, request->from, request->len,
(uint64_t)client->exp->size); client->exp->size);
return (request->type == NBD_CMD_WRITE || return (request->type == NBD_CMD_WRITE ||
request->type == NBD_CMD_WRITE_ZEROES) ? -ENOSPC : -EINVAL; request->type == NBD_CMD_WRITE_ZEROES) ? -ENOSPC : -EINVAL;
} }

29
qemu-nbd.c
View File

@ -176,7 +176,7 @@ static void read_partition(uint8_t *p, struct partition_record *r)
} }
static int find_partition(BlockBackend *blk, int partition, static int find_partition(BlockBackend *blk, int partition,
off_t *offset, off_t *size) uint64_t *offset, uint64_t *size)
{ {
struct partition_record mbr[4]; struct partition_record mbr[4];
uint8_t data[MBR_SIZE]; uint8_t data[MBR_SIZE];
@ -500,14 +500,14 @@ int main(int argc, char **argv)
{ {
BlockBackend *blk; BlockBackend *blk;
BlockDriverState *bs; BlockDriverState *bs;
off_t dev_offset = 0; uint64_t dev_offset = 0;
uint16_t nbdflags = 0; uint16_t nbdflags = 0;
bool disconnect = false; bool disconnect = false;
const char *bindto = NULL; const char *bindto = NULL;
const char *port = NULL; const char *port = NULL;
char *sockpath = NULL; char *sockpath = NULL;
char *device = NULL; char *device = NULL;
off_t fd_size; int64_t fd_size;
QemuOpts *sn_opts = NULL; QemuOpts *sn_opts = NULL;
const char *sn_id_or_name = NULL; const char *sn_id_or_name = NULL;
const char *sopt = "hVb:o:p:rsnP:c:dvk:e:f:tl:x:T:D:B:"; const char *sopt = "hVb:o:p:rsnP:c:dvk:e:f:tl:x:T:D:B:";
@ -665,10 +665,6 @@ int main(int argc, char **argv)
error_report("Invalid offset `%s'", optarg); error_report("Invalid offset `%s'", optarg);
exit(EXIT_FAILURE); exit(EXIT_FAILURE);
} }
if (dev_offset < 0) {
error_report("Offset must be positive `%s'", optarg);
exit(EXIT_FAILURE);
}
break; break;
case 'l': case 'l':
if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) { if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) {
@ -1005,15 +1001,14 @@ int main(int argc, char **argv)
} }
if (dev_offset >= fd_size) { if (dev_offset >= fd_size) {
error_report("Offset (%lld) has to be smaller than the image size " error_report("Offset (%" PRIu64 ") has to be smaller than the image "
"(%lld)", "size (%" PRId64 ")", dev_offset, fd_size);
(long long int)dev_offset, (long long int)fd_size);
exit(EXIT_FAILURE); exit(EXIT_FAILURE);
} }
fd_size -= dev_offset; fd_size -= dev_offset;
if (partition != -1) { if (partition != -1) {
off_t limit; uint64_t limit;
if (dev_offset) { if (dev_offset) {
error_report("Cannot request partition and offset together"); error_report("Cannot request partition and offset together");
@ -1027,15 +1022,13 @@ int main(int argc, char **argv)
} }
/* /*
* MBR partition limits are (32-bit << 9); this assert lets * MBR partition limits are (32-bit << 9); this assert lets
* the compiler know that we have two positive values that * the compiler know that we can't overflow 64 bits.
* can't overflow 64 bits.
*/ */
assert(dev_offset >= 0 && dev_offset + limit >= dev_offset); assert(dev_offset + limit >= dev_offset);
if (dev_offset + limit > fd_size) { if (dev_offset + limit > fd_size) {
error_report("Discovered partition %d at offset %lld size %lld, " error_report("Discovered partition %d at offset %" PRIu64
"but size exceeds file length %lld", partition, " size %" PRIu64 ", but size exceeds file length %"
(long long int) dev_offset, (long long int) limit, PRId64, partition, dev_offset, limit, fd_size);
(long long int) fd_size);
exit(EXIT_FAILURE); exit(EXIT_FAILURE);
} }
fd_size = limit; fd_size = limit;