[patch 2/2] gru: cleanup gru_dump_context() a little

From: Dan Carpenter
Date: Thu Jan 30 2014 - 07:11:18 EST


"ret" is zero here so we can remove the "!ret" part of the condition.
"uhdr" is alread a __user pointer so we can remove the cast.

Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
---
Btw, speaking of __user pointers there are some places where we
dereference them in this file. It's not a security problem because we
have already used copy_to_user() to successfully write to the pointer at
point. But if you have something like PAX which puts user pointers and
kernel pointers in a separate address space then this will cause
problems.

Run sparse to see the issue.

diff --git a/drivers/misc/sgi-gru/grukdump.c b/drivers/misc/sgi-gru/grukdump.c
index 2bef3f76032a..a3700a56b8ff 100644
--- a/drivers/misc/sgi-gru/grukdump.c
+++ b/drivers/misc/sgi-gru/grukdump.c
@@ -178,10 +178,10 @@ static int gru_dump_context(struct gru_state *gru, int ctxnum,
hdr.cbrcnt = cbrcnt;
hdr.dsrcnt = dsrcnt;
hdr.cch_locked = cch_locked;
- if (!ret && copy_to_user((void __user *)uhdr, &hdr, sizeof(hdr)))
- ret = -EFAULT;
+ if (copy_to_user(uhdr, &hdr, sizeof(hdr)))
+ return -EFAULT;

- return ret ? ret : bytes;
+ return bytes;
}

int gru_dump_chiplet_request(unsigned long arg)
--
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