[29/34] [SCSI] megaraid_sas: fix for 32bit apps

[Greg KH <gregkh@suse.de>]

2.6.34-stable review patch.  If anyone has any objections, please let us know.

------------------

From: Tomas Henzl <thenzl@redhat.com>

commit b3dc1a212e5167984616445990c76056034f8eeb upstream.

It looks like this patch -

commit 7b2519afa1abd1b9f63aa1e90879307842422dae
Author: Yang, Bo <Bo.Yang@lsi.com>
Date:   Tue Oct 6 14:52:20 2009 -0600

    [SCSI] megaraid_sas: fix 64 bit sense pointer truncation

has caused a problem for 32bit programs with 64bit os -

http://bugzilla.kernel.org/show_bug.cgi?id=15001

fix by converting the user space 32bit pointer to a 64 bit one when
needed.

[jejb: fix up some 64 bit warnings]
Signed-off-by: Tomas Henzl <thenzl@redhat.com>
Cc: Bo Yang <Bo.Yang@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
 drivers/scsi/megaraid/megaraid_sas.c |   18 ++++++++++++++++--
 1 file changed, 16 insertions(+), 2 deletions(-)

--- a/drivers/scsi/megaraid/megaraid_sas.c
+++ b/drivers/scsi/megaraid/megaraid_sas.c
@@ -3282,6 +3282,7 @@ static int megasas_mgmt_compat_ioctl_fw(
 	    compat_alloc_user_space(sizeof(struct megasas_iocpacket));
 	int i;
 	int error = 0;
+	compat_uptr_t ptr;
 
 	if (clear_user(ioc, sizeof(*ioc)))
 		return -EFAULT;
@@ -3294,9 +3295,22 @@ static int megasas_mgmt_compat_ioctl_fw(
 	    copy_in_user(&ioc->sge_count, &cioc->sge_count, sizeof(u32)))
 		return -EFAULT;
 
-	for (i = 0; i < MAX_IOCTL_SGE; i++) {
-		compat_uptr_t ptr;
+	/*
+	 * The sense_ptr is used in megasas_mgmt_fw_ioctl only when
+	 * sense_len is not null, so prepare the 64bit value under
+	 * the same condition.
+	 */
+	if (ioc->sense_len) {
+		void __user **sense_ioc_ptr =
+			(void __user **)(ioc->frame.raw + ioc->sense_off);
+		compat_uptr_t *sense_cioc_ptr =
+			(compat_uptr_t *)(cioc->frame.raw + cioc->sense_off);
+		if (get_user(ptr, sense_cioc_ptr) ||
+		    put_user(compat_ptr(ptr), sense_ioc_ptr))
+			return -EFAULT;
+	}
 
+	for (i = 0; i < MAX_IOCTL_SGE; i++) {
 		if (get_user(ptr, &cioc->sgl[i].iov_base) ||
 		    put_user(compat_ptr(ptr), &ioc->sgl[i].iov_base) ||
 		    copy_in_user(&ioc->sgl[i].iov_len,