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[resend,v3,3/5] libata-scsi: use u8 array to store mode page copy

Message ID 57926727.840e420a.d7fc9.38dd@mx.google.com
State Not Applicable
Delegated to: David Miller
Headers show

Commit Message

Tom Yan July 22, 2016, 6:34 p.m. UTC 
From: Tom Yan <tom.ty89@gmail.com>

ata_mselect_*() would initialize a char array for storing a copy of
the current mode page. However, char could be signed char. In that
case, bytes larger than 127 would be converted to negative number.

For example, 0xff from def_control_mpage[] would become -1. This
prevented ata_mselect_control() from working at all, since when it
did the read-only bits check, there would always be a mismatch.

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

Comments

Tejun Heo Aug. 9, 2016, 8:13 p.m. UTC | #1 
On Sat, Jul 23, 2016 at 02:34:08AM +0800, tom.ty89@gmail.com wrote:
> From: Tom Yan <tom.ty89@gmail.com>
> 
> ata_mselect_*() would initialize a char array for storing a copy of
> the current mode page. However, char could be signed char. In that
> case, bytes larger than 127 would be converted to negative number.
> 
> For example, 0xff from def_control_mpage[] would become -1. This
> prevented ata_mselect_control() from working at all, since when it
> did the read-only bits check, there would always be a mismatch.
> 
> Signed-off-by: Tom Yan <tom.ty89@gmail.com>

Applied to libata/for-4.9.

Thanks.
diff mbox

Patch

diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index 4a4e6f1..5cfcb4b 100644
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -3610,7 +3610,7 @@  static int ata_mselect_caching(struct ata_queued_cmd *qc,
 {
 	struct ata_taskfile *tf = &qc->tf;
 	struct ata_device *dev = qc->dev;
-	char mpage[CACHE_MPAGE_LEN];
+	u8 mpage[CACHE_MPAGE_LEN];
 	u8 wce, mask;
 	int i;
 
@@ -3668,7 +3668,7 @@  static int ata_mselect_control(struct ata_queued_cmd *qc,
 			       const u8 *buf, int len, u16 *fp)
 {
 	struct ata_device *dev = qc->dev;
-	char mpage[CONTROL_MPAGE_LEN];
+	u8 mpage[CONTROL_MPAGE_LEN];
 	u8 d_sense, mask;
 	int i;