All of lore.kernel.org
 help / color / mirror / Atom feed
* [PATCH v2 RESEND] libata: if T_LENGTH is zero, dma direction should be DMA_NONE
@ 2021-12-14 14:45 George Kennedy
  2021-12-14 23:42 ` Damien Le Moal
  2021-12-17  0:56 ` Damien Le Moal
  0 siblings, 2 replies; 3+ messages in thread
From: George Kennedy @ 2021-12-14 14:45 UTC (permalink / raw)
  To: damien.lemoal; +Cc: george.kennedy, linux-ide, linux-kernel, stable

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>
---
Used the Maintainers suggested fix.

 drivers/ata/libata-scsi.c | 15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)

diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index 1b84d55..313e947 100644
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -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;
-- 
1.8.3.1


^ permalink raw reply related	[flat|nested] 3+ messages in thread

* Re: [PATCH v2 RESEND] libata: if T_LENGTH is zero, dma direction should be DMA_NONE
  2021-12-14 14:45 [PATCH v2 RESEND] libata: if T_LENGTH is zero, dma direction should be DMA_NONE George Kennedy
@ 2021-12-14 23:42 ` Damien Le Moal
  2021-12-17  0:56 ` Damien Le Moal
  1 sibling, 0 replies; 3+ messages in thread
From: Damien Le Moal @ 2021-12-14 23:42 UTC (permalink / raw)
  To: George Kennedy; +Cc: linux-ide, linux-kernel

On 2021/12/14 23:45, 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@vger.kernel.org>

George,

FYI, you should not send patches that need backporting to
stable@vger.kernel.org. The above Cc: tag will do that automatically.

> Reported-by: syzkaller<syzkaller@googlegroups.com>
> Signed-off-by: George Kennedy<george.kennedy@oracle.com>
> ---
> Used the Maintainers suggested fix.

The usual way of writing this is something like:

Changes from v1:
* Blah

This way, if you need a v3, v4, etc, you can keep the previous changes
description and add new ones on top.

> 
>  drivers/ata/libata-scsi.c | 15 +++++++++++++--
>  1 file changed, 13 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
> index 1b84d55..313e947 100644
> --- a/drivers/ata/libata-scsi.c
> +++ b/drivers/ata/libata-scsi.c
> @@ -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;

This look OK to me. Will apply.


-- 
Damien Le Moal
Western Digital Research

^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: [PATCH v2 RESEND] libata: if T_LENGTH is zero, dma direction should be DMA_NONE
  2021-12-14 14:45 [PATCH v2 RESEND] libata: if T_LENGTH is zero, dma direction should be DMA_NONE George Kennedy
  2021-12-14 23:42 ` Damien Le Moal
@ 2021-12-17  0:56 ` Damien Le Moal
  1 sibling, 0 replies; 3+ messages in thread
From: Damien Le Moal @ 2021-12-17  0:56 UTC (permalink / raw)
  To: George Kennedy; +Cc: linux-ide

On 12/14/21 23:45, 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@vger.kernel.org>
> Reported-by: syzkaller<syzkaller@googlegroups.com>
> Signed-off-by: George Kennedy<george.kennedy@oracle.com>
> ---
> Used the Maintainers suggested fix.
> 
>  drivers/ata/libata-scsi.c | 15 +++++++++++++--
>  1 file changed, 13 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
> index 1b84d55..313e947 100644
> --- a/drivers/ata/libata-scsi.c
> +++ b/drivers/ata/libata-scsi.c
> @@ -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;
> 

Applied to for-5.16-fixes. Thanks !

-- 
Damien Le Moal
Western Digital Research

^ permalink raw reply	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2021-12-17  0:56 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-12-14 14:45 [PATCH v2 RESEND] libata: if T_LENGTH is zero, dma direction should be DMA_NONE George Kennedy
2021-12-14 23:42 ` Damien Le Moal
2021-12-17  0:56 ` Damien Le Moal

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.