Commit 041058a1 authored Oct 14, 2013 by Heiko Carstens Committed by Martin Schwidefsky Oct 24, 2013

s390/cmm: make copy_from_user() invocation provably correct



Get rid of these two warnings:

In function 'copy_from_user',
    inlined from 'cmm_timeout_handler' at arch/s390/mm/cmm.c:310:
      uaccess.h:303: warning: call to 'copy_from_user_overflow' declared
      with attribute warning: copy_from_user() buffer size is not provably
      correct
In function 'copy_from_user',
    inlined from 'cmm_pages_handler' at arch/s390/mm/cmm.c:270:
      uaccess.h:303: warning: call to 'copy_from_user_overflow' declared
      with attribute warning: copy_from_user() buffer size is not provably
      correct

Change the "len" type to unsigned int, so we can make sure that there is no
buffer overflow. This also generates less code.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

parent 160d378e

arch/s390/mm/cmm.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -257,8 +257,8 @@ static int cmm_pages_handler(ctl_table ctl, int write, void __user buffer,
		size_t lenp, loff_t ppos)
		{
		char buf[16], *p;
		unsigned int len;
		long nr;
		int len;

		if (!lenp \|\| (ppos && !write)) {
		*lenp = 0;
		@@ -298,7 +298,7 @@ static int cmm_timeout_handler(ctl_table ctl, int write, void __user buffer,
		{
		char buf[64], *p;
		long nr, seconds;
		int len;
		unsigned int len;

		if (!lenp \|\| (ppos && !write)) {
		*lenp = 0;