diff options
author | Nicholas Bellinger <nab@linux-iscsi.org> | 2013-10-02 02:04:40 +0200 |
---|---|---|
committer | Nicholas Bellinger <nab@linux-iscsi.org> | 2013-10-03 13:24:07 +0200 |
commit | db60df88ec39715fc3fb2a846cf35837e074c11d (patch) | |
tree | 12b29dda83448869226325fad6ea67e2882c6b0b | |
parent | target: Fix recursive COMPARE_AND_WRITE callback failure (diff) | |
download | linux-db60df88ec39715fc3fb2a846cf35837e074c11d.tar.xz linux-db60df88ec39715fc3fb2a846cf35837e074c11d.zip |
target: Fail on non zero scsi_status in compare_and_write_callback
This patch addresses a bug for backends such as IBLOCK that perform
asynchronous completion via transport_complete_cmd(), that will call
target_complete_failure_work() -> transport_generic_request_failure(),
upon exception status and invoke cmd->transport_complete_callback()
-> compare_and_write_callback() incorrectly during the failure case.
It adds a check for a non zero se_cmd->scsi_status within the first
invocation of compare_and_write_callback(), and will jump to out plus
up se_device->caw_sem before exiting the callback.
Reported-by: Thomas Glanzmann <thomas@glanzmann.de>
Tested-by: Thomas Glanzmann <thomas@glanzmann.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
-rw-r--r-- | drivers/target/target_core_sbc.c | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/drivers/target/target_core_sbc.c b/drivers/target/target_core_sbc.c index 1393d0ed746a..4714c6f8da4b 100644 --- a/drivers/target/target_core_sbc.c +++ b/drivers/target/target_core_sbc.c @@ -372,7 +372,7 @@ static sense_reason_t compare_and_write_callback(struct se_cmd *cmd) { struct se_device *dev = cmd->se_dev; struct scatterlist *write_sg = NULL, *sg; - unsigned char *buf, *addr; + unsigned char *buf = NULL, *addr; struct sg_mapping_iter m; unsigned int offset = 0, len; unsigned int nlbas = cmd->t_task_nolb; @@ -387,6 +387,15 @@ static sense_reason_t compare_and_write_callback(struct se_cmd *cmd) */ if (!cmd->t_data_sg || !cmd->t_bidi_data_sg) return TCM_NO_SENSE; + /* + * Immediately exit + release dev->caw_sem if command has already + * been failed with a non-zero SCSI status. + */ + if (cmd->scsi_status) { + pr_err("compare_and_write_callback: non zero scsi_status:" + " 0x%02x\n", cmd->scsi_status); + goto out; + } buf = kzalloc(cmd->data_length, GFP_KERNEL); if (!buf) { |