netdev - RE: [PATCH] rtlwifi: use %*ph[C] to dump small buffers

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]

Date:	Fri, 28 Sep 2012 10:04:41 +0100
From:	"David Laight" <David.Laight@...LAB.COM>
To:	"Joe Perches" <joe@...ches.com>,
	"Larry Finger" <Larry.Finger@...inger.net>
Cc:	"Andy Shevchenko" <andriy.shevchenko@...ux.intel.com>,
	"Chaoming Li" <chaoming_li@...lsil.com.cn>,
	"David S. Miller" <davem@...emloft.net>,
	<linux-wireless@...r.kernel.org>, <netdev@...r.kernel.org>
Subject: RE: [PATCH] rtlwifi: use %*ph[C] to dump small buffers

> > Index: wireless-testing-new/drivers/net/wireless/rtlwifi/rtl8192ce/hw.c
> > ===================================================================
> > --- wireless-testing-new.orig/drivers/net/wireless/rtlwifi/rtl8192ce/hw.c
> > +++ wireless-testing-new/drivers/net/wireless/rtlwifi/rtl8192ce/hw.c
> > @@ -1964,8 +1965,9 @@ static void rtl92ce_update_hal_rate_mask
> >
> >          RT_TRACE(rtlpriv, COMP_RATR, DBG_DMESG,
> >                   "ratr_bitmap :%x\n", ratr_bitmap);
> > -       *(u32 *)&rate_mask = (ratr_bitmap & 0x0fffffff) |
> > -                                    (ratr_index << 28);
> > +       for (i = 0; i < 3; i++)
> > +               rate_mask[i] = ratr_bitmap & (0xff << (i * 4));
> 
> rate_mask is u8, doesn't this needs (calc) >> (i * 8)
> 
> > +       rate_mask[3] = (ratr_bitmap & 0x0f000000) | (ratr_index << 28);
> 
> Perhaps you meant:
> 
> 		((ratr_bitmap & 0x0f000000) >> 24) | (ratr_index << 4)

I'd just do:
	rate_mask[0] = ratr_bitmap;
	rate_mask[1] = ratr_bitmap >>= 8;
	rate_mask[2] = ratr_bitmap >>= 8;
	rate_mask[3] = (ratr_bitmap >> 8) & 0xf | ratr_index << 4;
which is, of course, little endian.
Which means it is different from the original code on big-endian systems.
So changing this here ought to require a change when the data is read.
So this either fixes, or adds, an endianness bug.

	David



--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html