megasas: do not read command more than once from frame

Avoid TOC-TOU bugs by passing the frame_cmd down, and checking
cmd->dcmd_opcode instead of cmd->frame->header.frame_cmd.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Paolo Bonzini 2017-06-01 17:23:13 +02:00
parent 5104fac853
commit 36c327a69d

View File

@ -1591,12 +1591,13 @@ static int megasas_handle_dcmd(MegasasState *s, MegasasCmd *cmd)
}
static int megasas_finish_internal_dcmd(MegasasCmd *cmd,
SCSIRequest *req)
SCSIRequest *req, size_t resid)
{
int retval = MFI_STAT_OK;
int lun = req->lun;
trace_megasas_dcmd_internal_finish(cmd->index, cmd->dcmd_opcode, lun);
cmd->iov_size -= resid;
switch (cmd->dcmd_opcode) {
case MFI_DCMD_PD_GET_INFO:
retval = megasas_pd_get_info_submit(req->dev, lun, cmd);
@ -1649,11 +1650,12 @@ static int megasas_enqueue_req(MegasasCmd *cmd, bool is_write)
}
static int megasas_handle_scsi(MegasasState *s, MegasasCmd *cmd,
bool is_logical)
int frame_cmd)
{
uint8_t *cdb;
bool is_write;
struct SCSIDevice *sdev = NULL;
bool is_logical = (frame_cmd == MFI_CMD_LD_SCSI_IO);
cdb = cmd->frame->pass.cdb;
@ -1661,7 +1663,7 @@ static int megasas_handle_scsi(MegasasState *s, MegasasCmd *cmd,
if (cmd->frame->header.target_id >= MFI_MAX_LD ||
cmd->frame->header.lun_id != 0) {
trace_megasas_scsi_target_not_present(
mfi_frame_desc[cmd->frame->header.frame_cmd], is_logical,
mfi_frame_desc[frame_cmd], is_logical,
cmd->frame->header.target_id, cmd->frame->header.lun_id);
return MFI_STAT_DEVICE_NOT_FOUND;
}
@ -1671,19 +1673,20 @@ static int megasas_handle_scsi(MegasasState *s, MegasasCmd *cmd,
cmd->iov_size = le32_to_cpu(cmd->frame->header.data_len);
trace_megasas_handle_scsi(mfi_frame_desc[cmd->frame->header.frame_cmd],
is_logical, cmd->frame->header.target_id,
trace_megasas_handle_scsi(mfi_frame_desc[frame_cmd], is_logical,
cmd->frame->header.target_id,
cmd->frame->header.lun_id, sdev, cmd->iov_size);
if (!sdev || (megasas_is_jbod(s) && is_logical)) {
trace_megasas_scsi_target_not_present(
mfi_frame_desc[cmd->frame->header.frame_cmd], is_logical,
mfi_frame_desc[frame_cmd], is_logical,
cmd->frame->header.target_id, cmd->frame->header.lun_id);
return MFI_STAT_DEVICE_NOT_FOUND;
}
if (cmd->frame->header.cdb_len > 16) {
trace_megasas_scsi_invalid_cdb_len(
mfi_frame_desc[cmd->frame->header.frame_cmd], is_logical,
mfi_frame_desc[frame_cmd], is_logical,
cmd->frame->header.target_id, cmd->frame->header.lun_id,
cmd->frame->header.cdb_len);
megasas_write_sense(cmd, SENSE_CODE(INVALID_OPCODE));
@ -1703,7 +1706,7 @@ static int megasas_handle_scsi(MegasasState *s, MegasasCmd *cmd,
cmd->frame->header.lun_id, cdb, cmd);
if (!cmd->req) {
trace_megasas_scsi_req_alloc_failed(
mfi_frame_desc[cmd->frame->header.frame_cmd],
mfi_frame_desc[frame_cmd],
cmd->frame->header.target_id, cmd->frame->header.lun_id);
megasas_write_sense(cmd, SENSE_CODE(NO_SENSE));
cmd->frame->header.scsi_status = BUSY;
@ -1725,11 +1728,11 @@ static int megasas_handle_scsi(MegasasState *s, MegasasCmd *cmd,
return MFI_STAT_INVALID_STATUS;
}
static int megasas_handle_io(MegasasState *s, MegasasCmd *cmd)
static int megasas_handle_io(MegasasState *s, MegasasCmd *cmd, int frame_cmd)
{
uint32_t lba_count, lba_start_hi, lba_start_lo;
uint64_t lba_start;
bool is_write = (cmd->frame->header.frame_cmd == MFI_CMD_LD_WRITE);
bool is_write = (frame_cmd == MFI_CMD_LD_WRITE);
uint8_t cdb[16];
int len;
struct SCSIDevice *sdev = NULL;
@ -1746,20 +1749,20 @@ static int megasas_handle_io(MegasasState *s, MegasasCmd *cmd)
}
trace_megasas_handle_io(cmd->index,
mfi_frame_desc[cmd->frame->header.frame_cmd],
mfi_frame_desc[frame_cmd],
cmd->frame->header.target_id,
cmd->frame->header.lun_id,
(unsigned long)lba_start, (unsigned long)lba_count);
if (!sdev) {
trace_megasas_io_target_not_present(cmd->index,
mfi_frame_desc[cmd->frame->header.frame_cmd],
mfi_frame_desc[frame_cmd],
cmd->frame->header.target_id, cmd->frame->header.lun_id);
return MFI_STAT_DEVICE_NOT_FOUND;
}
if (cmd->frame->header.cdb_len > 16) {
trace_megasas_scsi_invalid_cdb_len(
mfi_frame_desc[cmd->frame->header.frame_cmd], 1,
mfi_frame_desc[frame_cmd], 1,
cmd->frame->header.target_id, cmd->frame->header.lun_id,
cmd->frame->header.cdb_len);
megasas_write_sense(cmd, SENSE_CODE(INVALID_OPCODE));
@ -1781,7 +1784,7 @@ static int megasas_handle_io(MegasasState *s, MegasasCmd *cmd)
cmd->frame->header.lun_id, cdb, cmd);
if (!cmd->req) {
trace_megasas_scsi_req_alloc_failed(
mfi_frame_desc[cmd->frame->header.frame_cmd],
mfi_frame_desc[frame_cmd],
cmd->frame->header.target_id, cmd->frame->header.lun_id);
megasas_write_sense(cmd, SENSE_CODE(NO_SENSE));
cmd->frame->header.scsi_status = BUSY;
@ -1799,23 +1802,11 @@ static int megasas_handle_io(MegasasState *s, MegasasCmd *cmd)
return MFI_STAT_INVALID_STATUS;
}
static int megasas_finish_internal_command(MegasasCmd *cmd,
SCSIRequest *req, size_t resid)
{
int retval = MFI_STAT_INVALID_CMD;
if (cmd->frame->header.frame_cmd == MFI_CMD_DCMD) {
cmd->iov_size -= resid;
retval = megasas_finish_internal_dcmd(cmd, req);
}
return retval;
}
static QEMUSGList *megasas_get_sg_list(SCSIRequest *req)
{
MegasasCmd *cmd = req->hba_private;
if (cmd->frame->header.frame_cmd == MFI_CMD_DCMD) {
if (cmd->dcmd_opcode != -1) {
return NULL;
} else {
return &cmd->qsg;
@ -1829,7 +1820,7 @@ static void megasas_xfer_complete(SCSIRequest *req, uint32_t len)
trace_megasas_io_complete(cmd->index, len);
if (cmd->frame->header.frame_cmd != MFI_CMD_DCMD) {
if (cmd->dcmd_opcode != -1) {
scsi_req_continue(req);
return;
}
@ -1872,7 +1863,7 @@ static void megasas_command_complete(SCSIRequest *req, uint32_t status,
/*
* Internal command complete
*/
cmd_status = megasas_finish_internal_command(cmd, req, resid);
cmd_status = megasas_finish_internal_dcmd(cmd, req, resid);
if (cmd_status == MFI_STAT_INVALID_STATUS) {
return;
}
@ -1943,6 +1934,7 @@ static void megasas_handle_frame(MegasasState *s, uint64_t frame_addr,
{
uint8_t frame_status = MFI_STAT_INVALID_CMD;
uint64_t frame_context;
int frame_cmd;
MegasasCmd *cmd;
/*
@ -1961,7 +1953,8 @@ static void megasas_handle_frame(MegasasState *s, uint64_t frame_addr,
s->event_count++;
return;
}
switch (cmd->frame->header.frame_cmd) {
frame_cmd = cmd->frame->header.frame_cmd;
switch (frame_cmd) {
case MFI_CMD_INIT:
frame_status = megasas_init_firmware(s, cmd);
break;
@ -1972,18 +1965,15 @@ static void megasas_handle_frame(MegasasState *s, uint64_t frame_addr,
frame_status = megasas_handle_abort(s, cmd);
break;
case MFI_CMD_PD_SCSI_IO:
frame_status = megasas_handle_scsi(s, cmd, 0);
break;
case MFI_CMD_LD_SCSI_IO:
frame_status = megasas_handle_scsi(s, cmd, 1);
frame_status = megasas_handle_scsi(s, cmd, frame_cmd);
break;
case MFI_CMD_LD_READ:
case MFI_CMD_LD_WRITE:
frame_status = megasas_handle_io(s, cmd);
frame_status = megasas_handle_io(s, cmd, frame_cmd);
break;
default:
trace_megasas_unhandled_frame_cmd(cmd->index,
cmd->frame->header.frame_cmd);
trace_megasas_unhandled_frame_cmd(cmd->index, frame_cmd);
s->event_count++;
break;
}