From: Damien Le Moal <damien.lemoal@xxxxxxxxxxxxxxxxxx> [ Upstream commit f0aa59a33d2ac2267d260fe21eaf92500df8e7b4 ] Some USB-SATA adapters have broken behavior when an unsupported VPD page is probed: Depending on the VPD page number, a 4-byte header with a valid VPD page number but with a 0 length is returned. Currently, scsi_vpd_inquiry() only checks that the page number is valid to determine if the page is valid, which results in receiving only the 4-byte 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 following 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> Link: https://lore.kernel.org/r/20230322022211.116327-1-damien.lemoal@xxxxxxxxxxxxxxxxxx Reviewed-by: Benjamin Block <bblock@xxxxxxxxxxxxx> Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- 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 24c4c92543599..3cda5d26b66ca 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
