scsi: Add buf_len parameter to scsi_req_new()
When a SCSI command is received from the guest, the CDB length implied
by the first byte might exceed the number of bytes the guest sent. In
this case scsi_req_new() will read uninitialized data, causing
unpredictable behavior.
Adds the buf_len parameter to scsi_req_new() and plumbs it through the
call stack.
Signed-off-by: John Millikin <john@john-millikin.com>
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1127
Message-Id: <20220817053458.698416-1-john@john-millikin.com>
[Fill in correct length for adapters other than ESP. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/hw/scsi/esp.c b/hw/scsi/esp.c
index c799c19..2ff18ce 100644
--- a/hw/scsi/esp.c
+++ b/hw/scsi/esp.c
@@ -292,7 +292,7 @@
esp_fifo_pop_buf(&s->cmdfifo, buf, cmdlen);
current_lun = scsi_device_find(&s->bus, 0, s->current_dev->id, s->lun);
- s->current_req = scsi_req_new(current_lun, 0, s->lun, buf, s);
+ s->current_req = scsi_req_new(current_lun, 0, s->lun, buf, cmdlen, s);
datalen = scsi_req_enqueue(s->current_req);
s->ti_size = datalen;
fifo8_reset(&s->cmdfifo);
diff --git a/hw/scsi/lsi53c895a.c b/hw/scsi/lsi53c895a.c
index ad5f5e5..05a43ec 100644
--- a/hw/scsi/lsi53c895a.c
+++ b/hw/scsi/lsi53c895a.c
@@ -864,7 +864,7 @@
s->current = g_new0(lsi_request, 1);
s->current->tag = s->select_tag;
s->current->req = scsi_req_new(dev, s->current->tag, s->current_lun, buf,
- s->current);
+ s->dbc, s->current);
n = scsi_req_enqueue(s->current->req);
if (n) {
diff --git a/hw/scsi/megasas.c b/hw/scsi/megasas.c
index d5dfb41..7082456 100644
--- a/hw/scsi/megasas.c
+++ b/hw/scsi/megasas.c
@@ -1062,7 +1062,7 @@
info->inquiry_data[0] = 0x7f; /* Force PQual 0x3, PType 0x1f */
info->vpd_page83[0] = 0x7f;
megasas_setup_inquiry(cmdbuf, 0, sizeof(info->inquiry_data));
- cmd->req = scsi_req_new(sdev, cmd->index, lun, cmdbuf, cmd);
+ cmd->req = scsi_req_new(sdev, cmd->index, lun, cmdbuf, sizeof(cmdbuf), cmd);
if (!cmd->req) {
trace_megasas_dcmd_req_alloc_failed(cmd->index,
"PD get info std inquiry");
@@ -1080,7 +1080,7 @@
return MFI_STAT_INVALID_STATUS;
} else if (info->inquiry_data[0] != 0x7f && info->vpd_page83[0] == 0x7f) {
megasas_setup_inquiry(cmdbuf, 0x83, sizeof(info->vpd_page83));
- cmd->req = scsi_req_new(sdev, cmd->index, lun, cmdbuf, cmd);
+ cmd->req = scsi_req_new(sdev, cmd->index, lun, cmdbuf, sizeof(cmdbuf), cmd);
if (!cmd->req) {
trace_megasas_dcmd_req_alloc_failed(cmd->index,
"PD get info vpd inquiry");
@@ -1268,7 +1268,7 @@
cmd->iov_buf = g_malloc0(dcmd_size);
info = cmd->iov_buf;
megasas_setup_inquiry(cdb, 0x83, sizeof(info->vpd_page83));
- cmd->req = scsi_req_new(sdev, cmd->index, lun, cdb, cmd);
+ cmd->req = scsi_req_new(sdev, cmd->index, lun, cdb, sizeof(cdb), cmd);
if (!cmd->req) {
trace_megasas_dcmd_req_alloc_failed(cmd->index,
"LD get info vpd inquiry");
@@ -1748,7 +1748,7 @@
return MFI_STAT_SCSI_DONE_WITH_ERROR;
}
- cmd->req = scsi_req_new(sdev, cmd->index, lun_id, cdb, cmd);
+ cmd->req = scsi_req_new(sdev, cmd->index, lun_id, cdb, cdb_len, cmd);
if (!cmd->req) {
trace_megasas_scsi_req_alloc_failed(
mfi_frame_desc(frame_cmd), target_id, lun_id);
@@ -1823,7 +1823,7 @@
megasas_encode_lba(cdb, lba_start, lba_count, is_write);
cmd->req = scsi_req_new(sdev, cmd->index,
- lun_id, cdb, cmd);
+ lun_id, cdb, cdb_len, cmd);
if (!cmd->req) {
trace_megasas_scsi_req_alloc_failed(
mfi_frame_desc(frame_cmd), target_id, lun_id);
diff --git a/hw/scsi/mptsas.c b/hw/scsi/mptsas.c
index 706cf0d..a90c254 100644
--- a/hw/scsi/mptsas.c
+++ b/hw/scsi/mptsas.c
@@ -324,7 +324,8 @@
}
req->sreq = scsi_req_new(sdev, scsi_io->MsgContext,
- scsi_io->LUN[1], scsi_io->CDB, req);
+ scsi_io->LUN[1], scsi_io->CDB,
+ scsi_io->CDBLength, req);
if (req->sreq->cmd.xfer > scsi_io->DataLength) {
goto overrun;
diff --git a/hw/scsi/scsi-bus.c b/hw/scsi/scsi-bus.c
index b2e2bc3..cc71524 100644
--- a/hw/scsi/scsi-bus.c
+++ b/hw/scsi/scsi-bus.c
@@ -102,15 +102,15 @@
}
int scsi_bus_parse_cdb(SCSIDevice *dev, SCSICommand *cmd, uint8_t *buf,
- void *hba_private)
+ size_t buf_len, void *hba_private)
{
SCSIBus *bus = DO_UPCAST(SCSIBus, qbus, dev->qdev.parent_bus);
int rc;
assert(cmd->len == 0);
- rc = scsi_req_parse_cdb(dev, cmd, buf);
+ rc = scsi_req_parse_cdb(dev, cmd, buf, buf_len);
if (bus->info->parse_cdb) {
- rc = bus->info->parse_cdb(dev, cmd, buf, hba_private);
+ rc = bus->info->parse_cdb(dev, cmd, buf, buf_len, hba_private);
}
return rc;
}
@@ -703,7 +703,7 @@
}
SCSIRequest *scsi_req_new(SCSIDevice *d, uint32_t tag, uint32_t lun,
- uint8_t *buf, void *hba_private)
+ uint8_t *buf, size_t buf_len, void *hba_private)
{
SCSIBus *bus = DO_UPCAST(SCSIBus, qbus, d->qdev.parent_bus);
const SCSIReqOps *ops;
@@ -734,9 +734,9 @@
}
if (ops != NULL || !sc->parse_cdb) {
- ret = scsi_req_parse_cdb(d, &cmd, buf);
+ ret = scsi_req_parse_cdb(d, &cmd, buf, buf_len);
} else {
- ret = sc->parse_cdb(d, &cmd, buf, hba_private);
+ ret = sc->parse_cdb(d, &cmd, buf, buf_len, hba_private);
}
if (ret != 0) {
@@ -1308,7 +1308,8 @@
}
}
-int scsi_req_parse_cdb(SCSIDevice *dev, SCSICommand *cmd, uint8_t *buf)
+int scsi_req_parse_cdb(SCSIDevice *dev, SCSICommand *cmd, uint8_t *buf,
+ size_t buf_len)
{
int rc;
int len;
@@ -1713,7 +1714,11 @@
qemu_get_buffer(f, buf, sizeof(buf));
qemu_get_be32s(f, &tag);
qemu_get_be32s(f, &lun);
- req = scsi_req_new(s, tag, lun, buf, NULL);
+ /*
+ * A too-short CDB would have been rejected by scsi_req_new, so just use
+ * SCSI_CMD_BUF_SIZE as the CDB length.
+ */
+ req = scsi_req_new(s, tag, lun, buf, sizeof(buf), NULL);
req->retry = (sbyte == 1);
if (bus->info->load_request) {
req->hba_private = bus->info->load_request(f, req);
diff --git a/hw/scsi/scsi-disk.c b/hw/scsi/scsi-disk.c
index efee673..399e178 100644
--- a/hw/scsi/scsi-disk.c
+++ b/hw/scsi/scsi-disk.c
@@ -3030,14 +3030,15 @@
}
static int scsi_block_parse_cdb(SCSIDevice *d, SCSICommand *cmd,
- uint8_t *buf, void *hba_private)
+ uint8_t *buf, size_t buf_len,
+ void *hba_private)
{
SCSIDiskState *s = DO_UPCAST(SCSIDiskState, qdev, d);
if (scsi_block_is_passthrough(s, buf)) {
- return scsi_bus_parse_cdb(&s->qdev, cmd, buf, hba_private);
+ return scsi_bus_parse_cdb(&s->qdev, cmd, buf, buf_len, hba_private);
} else {
- return scsi_req_parse_cdb(&s->qdev, cmd, buf);
+ return scsi_req_parse_cdb(&s->qdev, cmd, buf, buf_len);
}
}
diff --git a/hw/scsi/scsi-generic.c b/hw/scsi/scsi-generic.c
index 3d35d30..92cce20 100644
--- a/hw/scsi/scsi-generic.c
+++ b/hw/scsi/scsi-generic.c
@@ -791,9 +791,10 @@
};
static int scsi_generic_parse_cdb(SCSIDevice *dev, SCSICommand *cmd,
- uint8_t *buf, void *hba_private)
+ uint8_t *buf, size_t buf_len,
+ void *hba_private)
{
- return scsi_bus_parse_cdb(dev, cmd, buf, hba_private);
+ return scsi_bus_parse_cdb(dev, cmd, buf, buf_len, hba_private);
}
static void scsi_generic_class_initfn(ObjectClass *klass, void *data)
diff --git a/hw/scsi/spapr_vscsi.c b/hw/scsi/spapr_vscsi.c
index e320cca..0a8cbf5 100644
--- a/hw/scsi/spapr_vscsi.c
+++ b/hw/scsi/spapr_vscsi.c
@@ -783,6 +783,7 @@
union srp_iu *srp = &req_iu(req)->srp;
SCSIDevice *sdev;
int n, lun;
+ size_t cdb_len = sizeof (srp->cmd.cdb) + (srp->cmd.add_cdb_len & ~3);
if ((srp->cmd.lun == 0 || be64_to_cpu(srp->cmd.lun) == SRP_REPORT_LUNS_WLUN)
&& srp->cmd.cdb[0] == REPORT_LUNS) {
@@ -801,7 +802,7 @@
} return 1;
}
- req->sreq = scsi_req_new(sdev, req->qtag, lun, srp->cmd.cdb, req);
+ req->sreq = scsi_req_new(sdev, req->qtag, lun, srp->cmd.cdb, cdb_len, req);
n = scsi_req_enqueue(req->sreq);
trace_spapr_vscsi_queue_cmd(req->qtag, srp->cmd.cdb[0],
diff --git a/hw/scsi/virtio-scsi.c b/hw/scsi/virtio-scsi.c
index 4141ddd..41f2a56 100644
--- a/hw/scsi/virtio-scsi.c
+++ b/hw/scsi/virtio-scsi.c
@@ -622,7 +622,8 @@
}
static int virtio_scsi_parse_cdb(SCSIDevice *dev, SCSICommand *cmd,
- uint8_t *buf, void *hba_private)
+ uint8_t *buf, size_t buf_len,
+ void *hba_private)
{
VirtIOSCSIReq *req = hba_private;
@@ -696,7 +697,7 @@
virtio_scsi_ctx_check(s, d);
req->sreq = scsi_req_new(d, req->req.cmd.tag,
virtio_scsi_get_lun(req->req.cmd.lun),
- req->req.cmd.cdb, req);
+ req->req.cmd.cdb, vs->cdb_size, req);
if (req->sreq->cmd.mode != SCSI_XFER_NONE
&& (req->sreq->cmd.mode != req->mode ||
diff --git a/hw/scsi/vmw_pvscsi.c b/hw/scsi/vmw_pvscsi.c
index 4d9969f..91e2f85 100644
--- a/hw/scsi/vmw_pvscsi.c
+++ b/hw/scsi/vmw_pvscsi.c
@@ -730,7 +730,7 @@
r->sg.elemAddr = descr->dataAddr;
}
- r->sreq = scsi_req_new(d, descr->context, r->lun, descr->cdb, r);
+ r->sreq = scsi_req_new(d, descr->context, r->lun, descr->cdb, descr->cdbLen, r);
if (r->sreq->cmd.mode == SCSI_XFER_FROM_DEV &&
(descr->flags & PVSCSI_FLAG_CMD_DIR_TODEVICE)) {
r->cmp.hostStatus = BTSTAT_BADMSG;
diff --git a/hw/usb/dev-storage.c b/hw/usb/dev-storage.c
index dca62d5..9863969 100644
--- a/hw/usb/dev-storage.c
+++ b/hw/usb/dev-storage.c
@@ -415,7 +415,7 @@
cbw.cmd_len, s->data_len);
assert(le32_to_cpu(s->csw.residue) == 0);
s->scsi_len = 0;
- s->req = scsi_req_new(scsi_dev, tag, cbw.lun, cbw.cmd, NULL);
+ s->req = scsi_req_new(scsi_dev, tag, cbw.lun, cbw.cmd, cbw.cmd_len, NULL);
if (s->commandlog) {
scsi_req_print(s->req);
}
diff --git a/hw/usb/dev-uas.c b/hw/usb/dev-uas.c
index c9f295e..5192b06 100644
--- a/hw/usb/dev-uas.c
+++ b/hw/usb/dev-uas.c
@@ -71,7 +71,7 @@
uint8_t reserved_2;
uint64_t lun;
uint8_t cdb[16];
- uint8_t add_cdb[1]; /* not supported by QEMU */
+ uint8_t add_cdb[1];
} QEMU_PACKED uas_iu_command;
typedef struct {
@@ -699,6 +699,7 @@
UASRequest *req;
uint32_t len;
uint16_t tag = be16_to_cpu(iu->hdr.tag);
+ size_t cdb_len = sizeof(iu->command.cdb) + iu->command.add_cdb_length;
if (iu->command.add_cdb_length > 0) {
qemu_log_mask(LOG_UNIMP, "additional adb length not yet supported\n");
@@ -729,7 +730,7 @@
req->req = scsi_req_new(req->dev, req->tag,
usb_uas_get_lun(req->lun),
- iu->command.cdb, req);
+ iu->command.cdb, cdb_len, req);
if (uas->requestlog) {
scsi_req_print(req->req);
}
