linux-kernel - Re: [patch v2] usb: f_fs: off by one bug in _ffs_func

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

Message-ID: <57495F5D.1040607@bfs.de>
Date:	Sat, 28 May 2016 11:05:33 +0200
From:	walter harms <wharms@....de>
To:	Dan Carpenter <dan.carpenter@...cle.com>
CC:	Felipe Balbi <balbi@...nel.org>,
	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	Michal Nazarewicz <mina86@...a86.com>,
	Lars-Peter Clausen <lars@...afoo.de>,
	Robert Baldyga <r.baldyga@...sung.com>,
	Al Viro <viro@...IV.linux.org.uk>,
	Daniel Walter <dwalter@...ma-star.at>,
	"Du, Changbin" <changbin.du@...el.com>,
	Rui Miguel Silva <rui.silva@...aro.org>,
	linux-usb@...r.kernel.org, linux-kernel@...r.kernel.org,
	kernel-janitors@...r.kernel.org
Subject: Re: [patch v2] usb: f_fs: off by one bug in _ffs_func_bind()

much better readable than the original.
nice work

re,
 wh

Am 28.05.2016 06:48, schrieb Dan Carpenter:
> This loop is supposed to set all the .num[] values to -1 but it's off by
> one so it skips the first element and sets one element past the end of
> the array.
> 
> I've cleaned up the loop a little as well.
> 
> Fixes: ddf8abd25994 ('USB: f_fs: the FunctionFS driver')
> Signed-off-by: Dan Carpenter <dan.carpenter@...cle.com>
> ---
> v2: move the eps_ptr assignment outside the loop.
> 
> diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c
> index 73515d5..d26eb64 100644
> --- a/drivers/usb/gadget/function/f_fs.c
> +++ b/drivers/usb/gadget/function/f_fs.c
> @@ -2729,6 +2729,7 @@ static int _ffs_func_bind(struct usb_configuration *c,
>  		func->ffs->ss_descs_count;
>  
>  	int fs_len, hs_len, ss_len, ret, i;
> +	struct ffs_ep *eps_ptr;
>  
>  	/* Make it a single chunk, less management later on */
>  	vla_group(d);
> @@ -2777,12 +2778,9 @@ static int _ffs_func_bind(struct usb_configuration *c,
>  	       ffs->raw_descs_length);
>  
>  	memset(vla_ptr(vlabuf, d, inums), 0xff, d_inums__sz);
> -	for (ret = ffs->eps_count; ret; --ret) {
> -		struct ffs_ep *ptr;
> -
> -		ptr = vla_ptr(vlabuf, d, eps);
> -		ptr[ret].num = -1;
> -	}
> +	eps_ptr = vla_ptr(vlabuf, d, eps);
> +	for (i = 0; i < ffs->eps_count; i++)
> +		eps_ptr[i].num = -1;
>  
>  	/* Save pointers
>  	 * d_eps == vlabuf, func->eps used to kfree vlabuf later
> --
> To unsubscribe from this list: send the line "unsubscribe kernel-janitors" in
> the body of a message to majordomo@...r.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>