ata: libata-scsi: Fix offsets for the fixed format sense data

Correct the ATA PASS-THROUGH fixed format sense data offsets to conform
to SPC-6 and SAT-5 specifications. Additionally, set the VALID bit to
indicate that the INFORMATION field contains valid information.

INFORMATION
===========

SAT-5 Table 212 — "Fixed format sense data INFORMATION field for the ATA
PASS-THROUGH commands" defines the following format:

+------+------------+
| Byte |   Field    |
+------+------------+
|    0 | ERROR      |
|    1 | STATUS     |
|    2 | DEVICE     |
|    3 | COUNT(7:0) |
+------+------------+

SPC-6 Table 48 - "Fixed format sense data" specifies that the INFORMATION
field starts at byte 3 in sense buffer resulting in the following offsets
for the ATA PASS-THROUGH commands:

+------------+-------------------------+
|   Field    |  Offset in sense buffer |
+------------+-------------------------+
| ERROR      |  3                      |
| STATUS     |  4                      |
| DEVICE     |  5                      |
| COUNT(7:0) |  6                      |
+------------+-------------------------+

COMMAND-SPECIFIC INFORMATION
============================

SAT-5 Table 213 - "Fixed format sense data COMMAND-SPECIFIC INFORMATION
field for ATA PASS-THROUGH" defines the following format:

+------+-------------------+
| Byte |        Field      |
+------+-------------------+
|    0 | FLAGS | LOG INDEX |
|    1 | LBA (7:0)         |
|    2 | LBA (15:8)        |
|    3 | LBA (23:16)       |
+------+-------------------+

SPC-6 Table 48 - "Fixed format sense data" specifies that
the COMMAND-SPECIFIC-INFORMATION field starts at byte 8
in sense buffer resulting in the following offsets for
the ATA PASS-THROUGH commands:

Offsets of these fields in the fixed sense format are as follows:

+-------------------+-------------------------+
|       Field       |  Offset in sense buffer |
+-------------------+-------------------------+
| FLAGS | LOG INDEX |  8                      |
| LBA (7:0)         |  9                      |
| LBA (15:8)        |  10                     |
| LBA (23:16)       |  11                     |
+-------------------+-------------------------+

Reported-by: Akshat Jain <akshatzen@google.com>
Fixes: 11093cb1ef56 ("libata-scsi: generate correct ATA pass-through sense")
Cc: stable@vger.kernel.org
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Niklas Cassel <cassel@kernel.org>
Signed-off-by: Igor Pylypiv <ipylypiv@google.com>
Link: https://lore.kernel.org/r/20240702024735.1152293-2-ipylypiv@google.com
Signed-off-by: Niklas Cassel <cassel@kernel.org>

diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index cdf29b178ddc1ecd880348025eaa817c36e12b71..a0c68b0a00c410c006897ff355754bb124dc6d57 100644 (file)
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -855,7 +855,6 @@ static void ata_gen_passthru_sense(struct ata_queued_cmd *qc)
        struct scsi_cmnd *cmd = qc->scsicmd;
        struct ata_taskfile *tf = &qc->result_tf;
        unsigned char *sb = cmd->sense_buffer;
-       unsigned char *desc = sb + 8;
        u8 sense_key, asc, ascq;
 
        memset(sb, 0, SCSI_SENSE_BUFFERSIZE);
@@ -877,7 +876,8 @@ static void ata_gen_passthru_sense(struct ata_queued_cmd *qc)
                scsi_build_sense(cmd, 1, RECOVERED_ERROR, 0, 0x1D);
        }
 
-       if ((cmd->sense_buffer[0] & 0x7f) >= 0x72) {
+       if ((sb[0] & 0x7f) >= 0x72) {
+               unsigned char *desc;
                u8 len;
 
                /* descriptor format */
@@ -916,21 +916,21 @@ static void ata_gen_passthru_sense(struct ata_queued_cmd *qc)
                }
        } else {
                /* Fixed sense format */
-               desc[0] = tf->error;
-               desc[1] = tf->status;
-               desc[2] = tf->device;
-               desc[3] = tf->nsect;
-               desc[7] = 0;
+               sb[0] |= 0x80;
+               sb[3] = tf->error;
+               sb[4] = tf->status;
+               sb[5] = tf->device;
+               sb[6] = tf->nsect;
                if (tf->flags & ATA_TFLAG_LBA48)  {
-                       desc[8] |= 0x80;
+                       sb[8] |= 0x80;
                        if (tf->hob_nsect)
-                               desc[8] |= 0x40;
+                               sb[8] |= 0x40;
                        if (tf->hob_lbal || tf->hob_lbam || tf->hob_lbah)
-                               desc[8] |= 0x20;
+                               sb[8] |= 0x20;
                }
-               desc[9] = tf->lbal;
-               desc[10] = tf->lbam;
-               desc[11] = tf->lbah;
+               sb[9] = tf->lbal;
+               sb[10] = tf->lbam;
+               sb[11] = tf->lbah;
        }
 }