Messages in this thread | ![/](/images/icornerl.gif) | | Date | Wed, 15 Dec 2021 08:42:50 +0900 | Subject | Re: [PATCH v2 RESEND] libata: if T_LENGTH is zero, dma direction should be DMA_NONE | From | Damien Le Moal <> |
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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
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