diff options
| author | Nicholas Bellinger <nab@linux-iscsi.org> | 2012-10-02 14:00:33 -0700 |
|---|---|---|
| committer | Nicholas Bellinger <nab@linux-iscsi.org> | 2012-10-02 14:16:19 -0700 |
| commit | 944981c7e106af2aa004847e9177497856630980 (patch) | |
| tree | cc3f3e84f26a13c18adb7b84055147ed9ea45b88 /drivers/target/target_core_transport.c | |
| parent | 8f9f44f8957b262de717a48269a5ceca36c2b504 (diff) | |
target: Add control CDB READ payload zero work-around
This patch carries forward a work-around from tcm_loop to target
core code to explicitly clear control CDB READ paylods in order to
avoid bugs in scsi-generic user-space code for INQUIRY that do not
explicitly zero CDB payload memory.
(v2: Drop TARGET_SCF_MAP_CLEAR_MEM, and perform the explicit zero
of READ memory for all target_submit_cmd_map_sgls users)
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Diffstat (limited to 'drivers/target/target_core_transport.c')
| -rw-r--r-- | drivers/target/target_core_transport.c | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c index d96d9aa3a49..c33baff86aa 100644 --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -1539,6 +1539,27 @@ int target_submit_cmd_map_sgls(struct se_cmd *se_cmd, struct se_session *se_sess if (sgl_count != 0) { BUG_ON(!sgl); + /* + * A work-around for tcm_loop as some userspace code via + * scsi-generic do not memset their associated read buffers, + * so go ahead and do that here for type non-data CDBs. Also + * note that this is currently guaranteed to be a single SGL + * for this case by target core in target_setup_cmd_from_cdb() + * -> transport_generic_cmd_sequencer(). + */ + if (!(se_cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) && + se_cmd->data_direction == DMA_FROM_DEVICE) { + unsigned char *buf = NULL; + + if (sgl) + buf = kmap(sg_page(sgl)) + sgl->offset; + + if (buf) { + memset(buf, 0, sgl->length); + kunmap(sg_page(sgl)); + } + } + rc = transport_generic_map_mem_to_cmd(se_cmd, sgl, sgl_count, sgl_bidi, sgl_bidi_count); if (rc != 0) { |