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15 probable security holes in 2.4.5-ac8

CHECKER Joerg Reuter 4 participants 7 messages Jun 11, 2001

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To: [email protected], [email protected]
Subject: Re: [CHECKER] 15 probable security holes in 2.4.5-ac8
Date: Mon, 11 Jun 2001 15:45:07 +0200 (CEST)
From: [email protected] (Joerg Reuter)

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[BUG] (but i'm not sure whey we're missing the initial irq).
/u2/engler/mc/oses/linux/2.4.5-ac8/drivers/net/hamradio/scc.c:1772:scc_net_ioctl: ERROR:RANGE:1762:1772: Using user length "irq"as an array index for "Ivec" set by 'copy_from_user':1762 [val=1000]

			if (!arg) return -EFAULT;

Thats a real bug for other reaosns.

Nah, just a misconception (NB: the whole scc driver initialization is crap anyway -- but that part was written before we even had procfs; the next version will use procfs, but I'm not quite convinced that my current approach for the rewrite is correct. Fact is that the driver has to support far too many different parameters). The next version will also use the ISR of your z85230 HDLC driver, the z8530 seems to occasionally overwrite it's interrupt vector register with new status information before the old one was read.

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the iRQ might be > 16 on APIC using hosts

They won't assign IRQs above 15 for ISA cards, will they?

I gravely hope that nobody gets the idea to design a PCI card for the Z8530 without bus master DMA...

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or non x86

Granted. But I've no reports that anyone actually tried that, especially as the (unmodified) driver is only useful for packet radio purposes.

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Both fixed

How? ;-)

73,

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Joerg Reuter DL1BKE                             http://yaina.de/jreuter
And I make my way to where the warm scent of soil fills the evening air. 
Everything is waiting quietly out there....                 (Anne Clark)
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[snip]

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I gravely hope that nobody gets the idea to design a PCI card for the Z8530 without bus master DMA...

[snip]

What someone *really* needs to do is design a Z8530 adapter with a USB interface. The amateur radio community (well, the 56K'ers, at any rate), would love such a device. The PI2 card is a flakey beast, at best.

--John

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What someone *really* needs to do is design a Z8530 adapter with a USB interface. The amateur radio community (well, the 56K'ers, at any rate), would love such a device. The PI2 card is a flakey beast, at best.

You would be much better off attaching a straight ADC/DAC at say up to 256Kbits/8bit sampling and some control lines to the USB. That would also let people dumb the ridiculous 1960's technology they insist on using and run serious stuff like adaptive encoders, golay codecs and the like and bring amateur packet radio out of the stone age

Alan

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What someone *really* needs to do is design a Z8530 adapter with a USB interface. The amateur radio community (well, the 56K'ers, at

any rate),

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would love such a device. The PI2 card is a flakey beast, at best.

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You would be much better off attaching a straight ADC/DAC at say up to 256Kbits/8bit sampling and some control lines to the USB. That would also let people dumb the ridiculous 1960's technology they insist on using and run serious stuff like adaptive encoders, golay codecs and the like and bring amateur packet radio out of the stone age

Alan

Ideally, yes. However, client side DSP at these kinds of data rates still isn't practical. Most people are lucky if they can get 9600 baud, although admittedly some of that is a function of trying to use a standard sound card with it's limited input bandwidth (apx 22Khz).

It also doesn't solve the bigger problem, which is existing 56K users that want to upgrade machines, but can't, because the PI2 card flakes out in almost all systems that have PCI. The card has some timing issues to start with, and are aggrevated by how almost all PCI chipsets implement the ISA bus side.

I don't currently have my 56K station up, but I keep an old ISA only 486DX/80 system around just so I can use the card once I get in a position to (living on a houseboat creates some space problems for both machines, and antennas).

I don't know if you're familiar with the Heatherington 56K design or not, but there's some information at his website, www.wa4dsy.org. Dale, for those that don't know, was one of the 2 (or 3, depending on how you count) founders of Hayes Microcomputer (D.C. Hayes, at the time), and did the SB-103 and Smartmodem-300 designs, plus many other designs.

-- John

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Ideally, yes. However, client side DSP at these kinds of data rates still isn't practical. Most people are lucky if they can get 9600 baud, although admittedly some of that is a function of trying to use a standard sound card with it's limited input bandwidth (apx 22Khz).

A P200 can do the DSP work required to do 9600 baud with full FEC. I doubt you'll find USB on anything slower

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I don't know if you're familiar with the Heatherington 56K design or not,

Not really. The last interesting thing I looked at was shifting arcnet into the 10GHz band for 1Mbit point to point links

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but there's some information at his website, www.wa4dsy.org. Dale, for

I recognize the call tho - NOS supported some of his stuff

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Hi Alan.

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Ideally, yes. However, client side DSP at these kinds of data rates still isn't practical. Most people are lucky if they can get 9600 baud, although admittedly some of that is a function of trying to use a standard sound card with it's limited input bandwidth (apx 22Khz).

A P200 can do the DSP work required to do 9600 baud with full FEC. I doubt you'll find USB on anything slower

I can list two machines with USB that are slower - and I run both of them...

1. P166 (non-MMX) based, with USB on the motherboard. Currently unused, but I plan on plugging a digital camera SmartMedia card reader into it when I get one.

2. 486dx4/120 with USB on a plug in ISA-bus card (I'm not joking either).

I'll admit that I was surprised to come across that ISA-bus USB card at a local radio rally, but as they only wanted £2.50 for it, I paid the pennies and tried it out. It works fine for my scanner interface although I've never tried it for anything else.

Best wishes from Riley.

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In reply to Joerg Reuter
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Granted. But I've no reports that anyone actually tried that, especially as the (unmodified) driver is only useful for packet radio purposes.

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Both fixed

How? ;-)

NR_IRQS is defined by each port. I used that. Its the blunt instrument approach until you do it nicely 8)