linux-kernel - Re: [patch] mfd: snprintf() returns largish values

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:	Fri, 13 Aug 2010 09:23:51 +0800
From:	Feng Tang <feng.tang@...el.com>
To:	Dan Carpenter <error27@...il.com>
CC:	Greg Kroah-Hartman <gregkh@...e.de>,
	Alan Cox <alan@...ux.intel.com>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"kernel-janitors@...r.kernel.org" <kernel-janitors@...r.kernel.org>
Subject: Re: [patch] mfd: snprintf() returns largish values

On Thu, 12 Aug 2010 15:50:09 +0800
Dan Carpenter <error27@...il.com> wrote:

> snprintf() returns the number of bytes which would have been written
> so it can be larger than the size of the buffer.  In this case it's
> fine, but people copy and paste this code so I've fixed it.
> 
> Signed-off-by: Dan Carpenter <error27@...il.com>
> 
> diff --git a/drivers/serial/mfd.c b/drivers/serial/mfd.c
> index bc9af50..5aa25e5 100644
> --- a/drivers/serial/mfd.c
> +++ b/drivers/serial/mfd.c
> @@ -171,6 +171,9 @@ static ssize_t port_show_regs(struct file *file,
> char __user *user_buf, len += snprintf(buf + len, HSU_REGS_BUFSIZE -
> len, "DIV: \t\t0x%08x\n", serial_in(up, UART_DIV));
>  
> +	if (len > HSU_REGS_BUFSIZE)
> +		len = HSU_REGS_BUFSIZE;
> +
>  	ret =  simple_read_from_buffer(user_buf, count, ppos, buf,
> len); kfree(buf);
>  	return ret;
> @@ -218,6 +221,9 @@ static ssize_t dma_show_regs(struct file *file,
> char __user *user_buf, len += snprintf(buf + len, HSU_REGS_BUFSIZE -
> len, "D0TSR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_D3TSR));
>  
> +	if (len > HSU_REGS_BUFSIZE)
> +		len = HSU_REGS_BUFSIZE;
> +
>  	ret =  simple_read_from_buffer(user_buf, count, ppos, buf,
> len); kfree(buf);
>  	return ret;

Hi Carpenter,

It looks ok to me, thanks,

- Feng
--
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/