[SCSI] fix bugs in scsi_vpd_inquiry()
Universally, SCSI functions assume the lengths fed in are those of the buffer
to DMA data to, not the lengths of the data minus the header.
scsi_vpd_inquiry() assumed the latter and got it wrong, so fix up all the
functions to use the correct assumption (and fix a bug where INQUIRY in SCSI-2
dcannot go over 255).
[jejb: Matthew posted an identical version of this at the same time I did]
Signed-off-by: Matthew Wilcox <matthew@wil.cx>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
diff --git a/drivers/scsi/scsi.c b/drivers/scsi/scsi.c
index 2de5f3a..b6e0307 100644
--- a/drivers/scsi/scsi.c
+++ b/drivers/scsi/scsi.c
@@ -994,7 +994,7 @@
* all the existing users tried this hard.
*/
result = scsi_execute_req(sdev, cmd, DMA_FROM_DEVICE, buffer,
- len + 4, NULL, 30 * HZ, 3, NULL);
+ len, NULL, 30 * HZ, 3, NULL);
if (result)
return result;
@@ -1021,13 +1021,14 @@
{
int i, result;
unsigned int len;
- unsigned char *buf = kmalloc(259, GFP_KERNEL);
+ const unsigned int init_vpd_len = 255;
+ unsigned char *buf = kmalloc(init_vpd_len, GFP_KERNEL);
if (!buf)
return NULL;
/* Ask for all the pages supported by this device */
- result = scsi_vpd_inquiry(sdev, buf, 0, 255);
+ result = scsi_vpd_inquiry(sdev, buf, 0, init_vpd_len);
if (result)
goto fail;
@@ -1050,12 +1051,12 @@
* Some pages are longer than 255 bytes. The actual length of
* the page is returned in the header.
*/
- len = (buf[2] << 8) | buf[3];
- if (len <= 255)
+ len = ((buf[2] << 8) | buf[3]) + 4;
+ if (len <= init_vpd_len)
return buf;
kfree(buf);
- buf = kmalloc(len + 4, GFP_KERNEL);
+ buf = kmalloc(len, GFP_KERNEL);
result = scsi_vpd_inquiry(sdev, buf, page, len);
if (result)
goto fail;