lkml.org 
[lkml]   [2007]   [Feb]   [1]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: Linux 2.6.20-rc7
Linus Torvalds wrote:
>
> On Wed, 31 Jan 2007, H. Peter Anvin wrote:
>> It would be interesting to know what the inode numbers are in the image; also,
>> what is the exact behaviour -- do you end up with a missing link, or do both
>> entries end up getting hard-linked to an empty file?
>
> Judging by the
>
> request_module: runaway loop modprobe binfmt-0000
>
> one or more of the hardlinked binaries (modprobe being one, but not
> necessarily the one that initially triggers hits) will read all zeroes-
>
> Or at least bytes at offsets 2 and 3 will read as zero, causing it to not
> be recognized as a proper binary, causing that "binfmt-0000" thing.
>

Or perhaps not read at all, which would explain the problem.

cpio represents a hard link as who headers with the same type and the
same file (inode) number and a link count that is > 1. Only the first
one contains data; the subsequent ones have length 0. It's fairly easy
for a bug in the decoder to truncate the file upon encountering the
second header, since this is somewhat of a special case (it would have
been better if the cpio format distinguished "hard link" explicitly, as
tar does.)

I will look into this as soon as I can, but as I'm currently in the
middle of job hunting it might take until the weekend.

-hpa
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2007-02-01 07:13    [W:0.061 / U:0.080 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site