target: Add missing DATA_SG_IO transport_cmd_get_valid_sectors check

This patch adds the missing transport_cmd_get_valid_sectors() check for
SCF_SCSI_DATA_SG_IO_CDB type payloads to ensure that a received LBA + range
does not exeed past the end of associated backend struct se_device.

This patch also fixes a bug in the failure path of transport_new_cmd_obj()
where this check can fail, so change to use a signed 'rc' and return '-EINVAL'
to signal proper transport_generic_request_failure() handling.

Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

1 files changed, 8 insertions, 7 deletions

diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c
index d385c317a7a4..ab61c5550852 100644
--- a/drivers/target/target_core_transport.c
+++ b/drivers/target/target_core_transport.c
@@ -3891,9 +3891,7 @@ EXPORT_SYMBOL(transport_generic_map_mem_to_cmd);
 static int transport_new_cmd_obj(struct se_cmd *cmd)
 {
         struct se_device *dev = cmd->se_dev;
-        u32 task_cdbs;
-        u32 rc;
-        int set_counts = 1;
+        int set_counts = 1, rc, task_cdbs;
 
         /*
          * Setup any BIDI READ tasks and memory from
@@ -3911,7 +3909,7 @@ static int transport_new_cmd_obj(struct se_cmd *cmd)
                         cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
                         cmd->scsi_sense_reason =
                                 TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
-                        return PYX_TRANSPORT_LU_COMM_FAILURE;
+                        return -EINVAL;
                 }
                 atomic_inc(&cmd->t_fe_count);
                 atomic_inc(&cmd->t_se_count);
@@ -3930,7 +3928,7 @@ static int transport_new_cmd_obj(struct se_cmd *cmd)
                 cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
                 cmd->scsi_sense_reason =
                         TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
-                return PYX_TRANSPORT_LU_COMM_FAILURE;
+                return -EINVAL;
         }
 
         if (set_counts) {
@@ -4248,10 +4246,13 @@ static u32 transport_allocate_tasks(
         struct scatterlist *sgl,
         unsigned int sgl_nents)
 {
-        if (cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB)
+        if (cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB) {
+                if (transport_cmd_get_valid_sectors(cmd) < 0)
+                        return -EINVAL;
+
                 return transport_allocate_data_tasks(cmd, lba, data_direction,
                                                      sgl, sgl_nents);
-        else
+        } else
                 return transport_allocate_control_task(cmd);
 
 }