4.9-stable review patch. If anyone has any objections, please let me know.
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From: Johannes Thumshirn jthumshirn@suse.de
commit 68c59fcea1f2c6a54c62aa896cc623c1b5bc9b47 upstream.
SG_DXFER_FROM_DEV transfers do not necessarily have a dxferp as we set it to NULL for the old sg_io read/write interface, but must have a length bigger than 0. This fixes a regression introduced by commit 28676d869bbb ("scsi: sg: check for valid direction before starting the request")
Signed-off-by: Johannes Thumshirn jthumshirn@suse.de Fixes: 28676d869bbb ("scsi: sg: check for valid direction before starting the request") Reported-by: Chris Clayton chris2553@googlemail.com Tested-by: Chris Clayton chris2553@googlemail.com Cc: Douglas Gilbert dgilbert@interlog.com Reviewed-by: Hannes Reinecke hare@suse.com Tested-by: Chris Clayton chris2553@googlemail.com Acked-by: Douglas Gilbert dgilbert@interlog.com Signed-off-by: Martin K. Petersen martin.petersen@oracle.com Cc: Cristian Crinteanu crinteanu.cristian@gmail.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/scsi/sg.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)
--- a/drivers/scsi/sg.c +++ b/drivers/scsi/sg.c @@ -758,8 +758,11 @@ static bool sg_is_valid_dxfer(sg_io_hdr_ if (hp->dxferp || hp->dxfer_len > 0) return false; return true; - case SG_DXFER_TO_DEV: case SG_DXFER_FROM_DEV: + if (hp->dxfer_len < 0) + return false; + return true; + case SG_DXFER_TO_DEV: case SG_DXFER_TO_FROM_DEV: if (!hp->dxferp || hp->dxfer_len == 0) return false;