From fef58a6096770ed6ab49103a430cc755254a74d9 Mon Sep 17 00:00:00 2001 From: Nicholas Bellinger Date: Tue, 15 Nov 2011 22:13:24 -0800 Subject: target: Reject SCSI data overflow for fabrics using transport_generic_map_mem_to_cmd This patch changes transport_generic_map_mem_to_cmd() to reject SCSI data overflow and to send exception status with CHECK_CONDITION + TCM_INVALID_CDB_FIELD for fabrics that are passing a pre-populated struct scatterlist (eg: tcm_loop and iscsi-target) being mapped into se_cmd->t_data_sg and se_cmd->t_data_nents. This addresses an OOPs where transport_allocate_data_tasks() would walk the incorrect post OVERFLOW cmd->data_length value beyond the end of the passed scatterlist. Cc: Christoph Hellwig Cc: Andy Grover Cc: stable@kernel.org Signed-off-by: Nicholas Bellinger --- drivers/target/target_core_transport.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'drivers/target') diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c index 8f29f472c50b..0bdb6badbf99 100644 --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -3411,6 +3411,18 @@ int transport_generic_map_mem_to_cmd( if ((cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB) || (cmd->se_cmd_flags & SCF_SCSI_CONTROL_SG_IO_CDB)) { + /* + * Reject SCSI data overflow with map_mem_to_cmd() as incoming + * scatterlists already have been set to follow what the fabric + * passes for the original expected data transfer length. + */ + if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) { + pr_warn("Rejecting SCSI DATA overflow for fabric using" + " SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC\n"); + cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION; + cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD; + return -EINVAL; + } cmd->t_data_sg = sgl; cmd->t_data_nents = sgl_count; -- cgit v1.2.3