[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <20081202140223.7d5f3538.akpm@linux-foundation.org>
Date: Tue, 2 Dec 2008 14:02:23 -0800
From: Andrew Morton <akpm@...ux-foundation.org>
To: roel kluin <roel.kluin@...il.com>
Cc: wli@...omorphy.com, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] hugetlb: unsigned ret cannot be negative.
On Sat, 29 Nov 2008 06:36:59 -0500
roel kluin <roel.kluin@...il.com> wrote:
> unsigned long ret cannot be negative, but ret can get -EFAULT.
>
> Signed-off-by: Roel Kluin <roel.kluin@...il.com>
> ---
> hugetlbfs_read_actor() returns int,
> see
> vi fs/hugetlbfs/inode.c +187
>
> diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
> index 61edc70..0af64e4 100644
> --- a/fs/hugetlbfs/inode.c
> +++ b/fs/hugetlbfs/inode.c
> @@ -252,6 +252,7 @@ static ssize_t hugetlbfs_read(struct file *filp, char __user *buf,
> for (;;) {
> struct page *page;
> unsigned long nr, ret;
> + int ra;
>
> /* nr is the maximum number of bytes to copy from this page */
> nr = huge_page_size(h);
> @@ -279,15 +280,16 @@ static ssize_t hugetlbfs_read(struct file *filp, char __user *buf,
> /*
> * We have the page, copy it to user space buffer.
> */
> - ret = hugetlbfs_read_actor(page, offset, buf, len, nr);
> + ra = hugetlbfs_read_actor(page, offset, buf, len, nr);
> }
> - if (ret < 0) {
> + if (ra < 0) {
> if (retval == 0)
> - retval = ret;
> + retval = ra;
> if (page)
> page_cache_release(page);
> goto out;
> }
> + ret = ra;
>
> offset += ret;
> retval += ret;
`ra' can obviously be used uninitialised here. The compiler reports
this, too.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists