From 0e2eb7d12eaa8e391bf5615d4271bb87a649caaa Mon Sep 17 00:00:00 2001 From: Bart Van Assche Date: Thu, 30 Mar 2017 10:12:39 -0700 Subject: [PATCH] target: Fix VERIFY and WRITE VERIFY command parsing Use the value of the BYTCHK field to determine the size of the Data-Out buffer. For VERIFY, honor the VRPROTECT, DPO and FUA fields. This patch avoids that LIO complains about a mismatch between the expected transfer length and the SCSI CDB length if the value of the BYTCHK field is 0. Signed-off-by: Bart Van Assche Cc: Max Lohrmann Cc: Signed-off-by: Nicholas Bellinger --- drivers/target/target_core_sbc.c | 71 ++++++++++++++++++++++++++++---- 1 file changed, 62 insertions(+), 9 deletions(-) diff --git a/drivers/target/target_core_sbc.c b/drivers/target/target_core_sbc.c index c194063f169b..ee35c90e3b8d 100644 --- a/drivers/target/target_core_sbc.c +++ b/drivers/target/target_core_sbc.c @@ -828,6 +828,59 @@ sbc_check_dpofua(struct se_device *dev, struct se_cmd *cmd, unsigned char *cdb) return 0; } +/** + * sbc_parse_verify - parse VERIFY, VERIFY_16 and WRITE VERIFY commands + * @cmd: (in) structure that describes the SCSI command to be parsed. + * @sectors: (out) Number of logical blocks on the storage medium that will be + * affected by the SCSI command. + * @bufflen: (out) Expected length of the SCSI Data-Out buffer. + */ +static sense_reason_t sbc_parse_verify(struct se_cmd *cmd, int *sectors, + u32 *bufflen) +{ + struct se_device *dev = cmd->se_dev; + u8 *cdb = cmd->t_task_cdb; + u8 bytchk = (cdb[1] >> 1) & 3; + sense_reason_t ret; + + switch (cdb[0]) { + case VERIFY: + case WRITE_VERIFY: + *sectors = transport_get_sectors_10(cdb); + cmd->t_task_lba = transport_lba_32(cdb); + break; + case VERIFY_16: + *sectors = transport_get_sectors_16(cdb); + cmd->t_task_lba = transport_lba_64(cdb); + break; + default: + WARN_ON_ONCE(true); + return TCM_UNSUPPORTED_SCSI_OPCODE; + } + + if (sbc_check_dpofua(dev, cmd, cdb)) + return TCM_INVALID_CDB_FIELD; + + ret = sbc_check_prot(dev, cmd, cdb, *sectors, true); + if (ret) + return ret; + + switch (bytchk) { + case 0: + *bufflen = 0; + break; + case 1: + *bufflen = sbc_get_size(cmd, *sectors); + cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB; + break; + default: + pr_err("Unsupported BYTCHK value %d for SCSI opcode %#x\n", + bytchk, cdb[0]); + return TCM_INVALID_CDB_FIELD; + } + return TCM_NO_SENSE; +} + sense_reason_t sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops) { @@ -895,7 +948,6 @@ sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops) cmd->execute_cmd = sbc_execute_rw; break; case WRITE_10: - case WRITE_VERIFY: sectors = transport_get_sectors_10(cdb); cmd->t_task_lba = transport_lba_32(cdb); @@ -909,6 +961,12 @@ sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops) cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB; cmd->execute_cmd = sbc_execute_rw; break; + case WRITE_VERIFY: + ret = sbc_parse_verify(cmd, §ors, &size); + if (ret) + return ret; + cmd->execute_cmd = sbc_execute_rw; + goto check_lba; case WRITE_12: sectors = transport_get_sectors_12(cdb); cmd->t_task_lba = transport_lba_32(cdb); @@ -1106,14 +1164,9 @@ sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops) break; case VERIFY: case VERIFY_16: - size = 0; - if (cdb[0] == VERIFY) { - sectors = transport_get_sectors_10(cdb); - cmd->t_task_lba = transport_lba_32(cdb); - } else { - sectors = transport_get_sectors_16(cdb); - cmd->t_task_lba = transport_lba_64(cdb); - } + ret = sbc_parse_verify(cmd, §ors, &size); + if (ret) + return ret; cmd->execute_cmd = sbc_emulate_noop; goto check_lba; case REZERO_UNIT: -- 2.20.1