From: Alexey Zaytsev <alexey.zaytsev@gmail.com>
Date: Wed, 10 Jun 2009 19:56:56 +0000 (-0700)
Subject: [SCSI] compat: don't perform unneeded copy in sg_io code
X-Git-Tag: v2.6.31-rc1~285^2~12
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=df59c0ad05182329688e514e5a9c3836fa208ea3;p=karo-tx-linux.git

[SCSI] compat: don't perform unneeded copy in sg_io code

The members from 'status' in struct sg_io_hdr to the last are used to
transfer information from kernel to user space.  The values that user
space sets are just ignored.

Signed-off-by: Alexey Zaytsev <alexey.zaytsev@gmail.com>
Acked-by: Jens Axboe <jens.axboe@oracle.com>
Acked-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
---

diff --git a/fs/compat_ioctl.c b/fs/compat_ioctl.c
index b83f6bcfa51a..905523cc281f 100644
--- a/fs/compat_ioctl.c
+++ b/fs/compat_ioctl.c
@@ -788,12 +788,6 @@ static int sg_ioctl_trans(unsigned int fd, unsigned int cmd, unsigned long arg)
 	if (put_user(compat_ptr(data), &sgio->usr_ptr))
 		return -EFAULT;
 
-	if (copy_in_user(&sgio->status, &sgio32->status,
-			 (4 * sizeof(unsigned char)) +
-			 (2 * sizeof(unsigned short)) +
-			 (3 * sizeof(int))))
-		return -EFAULT;
-
 	err = sys_ioctl(fd, cmd, (unsigned long) sgio);
 
 	if (err >= 0) {