[PATCH resend 4/5] libata-scsi: have all checks done before calling ata_mselect_*()

From: tom . ty89
Date: Thu Jul 21 2016 - 14:43:18 EST


From: Tom Yan <tom.ty89@xxxxxxxxx>

The one-page-at-a-time check in ata_scsi_mode_select_xlat() should
be done before either of the ata_mselect_*() is called.

Also updated the comment. We have more than one mode page that has
changeable bit since commit 06dbde5f3a44 ("libata: Implement
control mode page to select sense format").

Signed-off-by: Tom Yan <tom.ty89@xxxxxxxxx>

diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index 3c93341..6c424c5 100644
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -3837,6 +3837,12 @@ static unsigned int ata_scsi_mode_select_xlat(struct ata_queued_cmd *qc)
if (pg_len > len)
goto invalid_param_len;

+ /*
+ * Currently we only support setting one page at a time.
+ */
+ if (len > pg_len)
+ goto invalid_param;
+
switch (pg) {
case CACHE_MPAGE:
if (ata_mselect_caching(qc, p, pg_len, &fp) < 0) {
@@ -3855,13 +3861,6 @@ static unsigned int ata_scsi_mode_select_xlat(struct ata_queued_cmd *qc)
goto invalid_param;
}

- /*
- * Only one page has changeable data, so we only support setting one
- * page at a time.
- */
- if (len > pg_len)
- goto invalid_param;
-
return 0;

invalid_fld:
--
2.9.0