Bug 12375 - ext4_block_to_path block too big cause cpu to burn
Summary: ext4_block_to_path block too big cause cpu to burn
Alias: None
Product: File System
Classification: Unclassified
Component: ext4 (show other bugs)
Hardware: All Linux
: P1 normal
Assignee: Theodore Tso
Depends on:
Reported: 2009-01-07 02:56 UTC by David Maciejak
Modified: 2009-02-03 11:20 UTC (History)
0 users

See Also:
Kernel Version: 2.6.28
Regression: ---
Bisected commit-id:

kernel log extract (1.58 KB, text/x-log)
2009-01-07 02:57 UTC, David Maciejak
ext4 image poc (189.75 KB, application/x-bzip)
2009-01-07 02:57 UTC, David Maciejak
Patch to address this bug (1.90 KB, patch)
2009-01-17 15:44 UTC, Theodore Tso
Details | Diff

Description David Maciejak 2009-01-07 02:56:33 UTC
Latest working kernel version: none
Earliest failing kernel version: unknow
Distribution: ubuntu
Hardware Environment: dell optiplex 740
Software Environment:
Problem Description:
when mounting specially crafted ext4 image, after some few seconds (5s), kern.log is filled with some data and cpu reaches 100%
Steps to reproduce:
bunzip the image file enclosed and mount the image with  mount -t ext4 -o loop ext4.img /media/tmp

note: i also tried the 2.6.28-ext4-3 patch but it does not help


David Maciejak
Fortinet's FortiGuard Global Security Research Team
Comment 1 David Maciejak 2009-01-07 02:57:13 UTC
Created attachment 19685 [details]
kernel log extract
Comment 2 David Maciejak 2009-01-07 02:57:41 UTC
Created attachment 19686 [details]
ext4 image poc
Comment 3 Theodore Tso 2009-01-17 15:44:48 UTC
Created attachment 19872 [details]
Patch to address this bug

This patch should address this bug.  Thanks for reporting it!
Comment 4 Theodore Tso 2009-02-03 11:20:31 UTC
This patch has been merged into the Linux mainline and will be 2.6.29-rc4 and newer releases.

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