linux-kernel - Re: [PATCH] return hidden bug

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:	Sun, 21 Oct 2007 21:42:09 -0400
From:	Rik van Riel <riel@...hat.com>
To:	Roel Kluin <12o3l@...cali.nl>
Cc:	lkml <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] return hidden bug

On Mon, 22 Oct 2007 03:05:05 +0200
Roel Kluin <12o3l@...cali.nl> wrote:

>     return hidden bug
>     
>     Signed-off-by: Roel Kluin <12o3l@...cali.nl>
> 
> diff --git a/arch/alpha/kernel/pci_iommu.c
> b/arch/alpha/kernel/pci_iommu.c index e1c4707..6a69425 100644
> --- a/arch/alpha/kernel/pci_iommu.c
> +++ b/arch/alpha/kernel/pci_iommu.c
> @@ -365,8 +365,8 @@ pci_unmap_single(struct pci_dev *pdev, dma_addr_t
> dma_addr, size_t size, printk(KERN_ERR "Bogus pci_unmap_single:
> dma_addr %lx " " base %lx size %x\n", dma_addr, arena->dma_base,
>  		       arena->size);
> -		return;
>  		BUG();
> +		return;
>  	}
>  
>  	npages = calc_npages((dma_addr & ~PAGE_MASK) + size);

BUG() will terminate the process that runs into it, so you can
just remove the return alltogether.  If BUG() is hit, the return
will never be reached.

-- 
"Debugging is twice as hard as writing the code in the first place.
Therefore, if you write the code as cleverly as possible, you are,
by definition, not smart enough to debug it." - Brian W. Kernighan
-
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/