Some USB-SATA adapters have a broken behavior when a non supported VPD page is probed: depending on the VPD page number, a 4 byte header with a valid VPD page number but with a 0 lenghth is returned. Currently, scsi_vpd_inquiry() only checks that the page number is valid to determine if the page is supported, which results in VPD page users receiving only the 4 B header for the non existent page. This error manifests itself very often with page 0xb9 for the concurrent Positioning Ranges detection done by sd_read_cpr(), resulting in the error message: sd 0:0:0:0: [sda] Invalid Concurrent Positioning Ranges VPD page Prevent such misleading error message by adding a check in scsi_vpd_inquiry() to verify that the page length is not 0. Signed-off-by: Damien Le Moal <damien.lemoal@xxxxxxxxxxxxxxxxxx> --- drivers/scsi/scsi.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/drivers/scsi/scsi.c b/drivers/scsi/scsi.c index ab6e2d5e1430..c4bf99a842f3 100644 --- a/drivers/scsi/scsi.c +++ b/drivers/scsi/scsi.c @@ -314,11 +314,18 @@ static int scsi_vpd_inquiry(struct scsi_device *sdev, unsigned char *buffer, if (result) return -EIO; - /* Sanity check that we got the page back that we asked for */ + /* + * Sanity check that we got the page back that we asked for and that + * the page size is not 0. + */ if (buffer[1] != page) return -EIO; - return get_unaligned_be16(&buffer[2]) + 4; + result = get_unaligned_be16(&buffer[2]); + if (!result) + return -EIO; + + return result + 4; } static int scsi_get_vpd_size(struct scsi_device *sdev, u8 page) -- 2.39.2
