libata: if T_LENGTH is zero, dma direction should be DMA_NONE

Avoid data corruption by rejecting pass-through commands where
T_LENGTH is zero (No data is transferred) and the dma direction
is not DMA_NONE.

Cc: <stable@vger.kernel.org>
Reported-by: syzkaller<syzkaller@googlegroups.com>
Signed-off-by: George Kennedy<george.kennedy@oracle.com>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
This commit is contained in:
George Kennedy 2021-12-14 09:45:10 -05:00 committed by Damien Le Moal
parent 2585cf9dfa
commit 5da5231bb4

View File

@ -2859,8 +2859,19 @@ static unsigned int ata_scsi_pass_thru(struct ata_queued_cmd *qc)
goto invalid_fld;
}
if (ata_is_ncq(tf->protocol) && (cdb[2 + cdb_offset] & 0x3) == 0)
tf->protocol = ATA_PROT_NCQ_NODATA;
if ((cdb[2 + cdb_offset] & 0x3) == 0) {
/*
* When T_LENGTH is zero (No data is transferred), dir should
* be DMA_NONE.
*/
if (scmd->sc_data_direction != DMA_NONE) {
fp = 2 + cdb_offset;
goto invalid_fld;
}
if (ata_is_ncq(tf->protocol))
tf->protocol = ATA_PROT_NCQ_NODATA;
}
/* enable LBA */
tf->flags |= ATA_TFLAG_LBA;