On 12/13/2021 4:37 PM, Damien Le Moal wrote:
On 2021/12/14 0:33, George Kennedy wrote:
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@xxxxxxxxxxxxxxx> # 5.4.y
5.4 only ? What about other LTS versions ? They do not have that bug ?
Our distros are based on 5.4.y, 5.15.y and 4.14.y, so the fix should go
there,
but it looks like the fix is also needed in: 5.14.y, 5.13.y, 5.10.y, and
4.19.y.
Thank you,
George
Reported-by: syzkaller<syzkaller@xxxxxxxxxxxxxxxx>
Signed-off-by: George Kennedy<george.kennedy@xxxxxxxxxx>
---
drivers/ata/libata-scsi.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index 1b84d55..d428392 100644
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -2859,6 +2859,12 @@ static unsigned int ata_scsi_pass_thru(struct ata_queued_cmd *qc)
goto invalid_fld;
}
+ /* if T_LENGTH is zero (No data is transferred), then dir should be DMA_NONE */
+ if ((cdb[2 + cdb_offset] & 3) == 0 && scmd->sc_data_direction != DMA_NONE) {
+ fp = 2 + cdb_offset;
+ goto invalid_fld;
+ }
+
if (ata_is_ncq(tf->protocol) && (cdb[2 + cdb_offset] & 0x3) == 0)
tf->protocol = ATA_PROT_NCQ_NODATA;
-- 1.8.3.1
