diff --git a/drivers/target/target_core_sbc.c b/drivers/target/target_core_sbc.c
index 5c822fdc8f6f5eb346e3873ed0fc6df5f983666e..2cd9acdeb5434a57f10fbdeebc59ae7bcb7ef9ae 100644
--- a/drivers/target/target_core_sbc.c
+++ b/drivers/target/target_core_sbc.c
@@ -372,6 +372,13 @@ static sense_reason_t compare_and_write_callback(struct se_cmd *cmd)
 	sense_reason_t ret = TCM_NO_SENSE;
 	int rc, i;
 
+	/*
+	 * Handle early failure in transport_generic_request_failure(),
+	 * which will not have taken ->caw_mutex yet..
+	 */
+	if (!cmd->t_data_sg || !cmd->t_bidi_data_sg)
+		return TCM_NO_SENSE;
+
 	buf = kzalloc(cmd->data_length, GFP_KERNEL);
 	if (!buf) {
 		pr_err("Unable to allocate compare_and_write buf\n");
diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c
index e53c59ba745aa18c77230ba02b4e414be705e722..bcbc3d397badc9cdc5873c260ee9f9092924aeb1 100644
--- a/drivers/target/target_core_transport.c
+++ b/drivers/target/target_core_transport.c
@@ -1559,6 +1559,13 @@ void transport_generic_request_failure(struct se_cmd *cmd,
 	 * For SAM Task Attribute emulation for failed struct se_cmd
 	 */
 	transport_complete_task_attr(cmd);
+	/*
+	 * Handle special case for COMPARE_AND_WRITE failure, where the
+	 * callback is expected to drop the per device ->caw_mutex.
+	 */
+	if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
+	     cmd->transport_complete_callback)
+		cmd->transport_complete_callback(cmd);
 
 	switch (sense_reason) {
 	case TCM_NON_EXISTENT_LUN: