|Summary:||[RHEL4] [patch] cid-11 Avoid static buffer overruns in debugfs|
|Product:||Red Hat Enterprise Linux 4||Reporter:||Bryn M. Reeves <bmr>|
|Component:||e2fsprogs||Assignee:||Eric Sandeen <esandeen>|
|Status:||CLOSED ERRATA||QA Contact:||Jay Turner <jturner>|
|Fixed In Version:||RHBA-2007-0758||Doc Type:||Bug Fix|
|Doc Text:||Story Points:||---|
|Last Closed:||2007-11-15 16:01:32 UTC||Type:||---|
|oVirt Team:||---||RHEL 7.3 requirements from Atomic Host:|
|Cloudforms Team:||---||Target Upstream Version:|
|Bug Depends On:|
Description Bryn M. Reeves 2007-02-14 16:18:01 UTC
Description of problem: list_dir_proc uses a buffer allocated on the stack for the file name. This is sized as EXT2_NAME_LEN and the length of the string is checked: char name[EXT2_NAME_LEN]; ... thislen = ((dirent->name_len & 0xFF) < EXT2_NAME_LEN) ? (dirent->name_len & 0xFF) : EXT2_NAME_LEN; Finally, we copy the string and set the name[thislen] to '\0'. In the case that thislen == EXT2_NAME_LEN, the '\0' char is stored outside the bounds of the name array. Version-Release number of selected component (if applicable): e2fsprogs-1.35-12.4.EL4 How reproducible: 100% Steps to Reproduce: This isn't easy to reproduce as the stack layout (on i386 anyway) means that an overflow of 1 byte does not overwrite any other datastructures. 1. Create a filename with length equal to EXT2_NAME_LEN 2. Open the filesystem with debugfs running under gdb 3. Set a breakpoint on list_dir_proc 3. List directory contents 4. Continue until the long filename appears in *dirent 5. Store a known character in the byte following the end of name 6. Step through the routine until after the "name[thislen] = '\0';" Actual results: The byte after the end of name is overwritten. Expected results: The assignment stays within the array bounds.
Comment 1 Bryn M. Reeves 2007-02-14 16:18:01 UTC
Created attachment 148062 [details] Patch correcting array usage in ls_dir_proc
Comment 5 RHEL Product and Program Management 2007-05-09 07:43:26 UTC
This request was evaluated by Red Hat Product Management for inclusion in a Red Hat Enterprise Linux maintenance release. Product Management has requested further review of this request by Red Hat Engineering, for potential inclusion in a Red Hat Enterprise Linux Update release for currently deployed products. This request is not yet committed for inclusion in an Update release.
Comment 6 Eric Sandeen 2007-05-29 20:10:34 UTC
upstream commits for cid-11, cid-12, cid-13 at http://thunk.org/hg/e2fsprogs/?rev/4c321a4ecbd6
Comment 7 Benjamin Kahn 2007-06-08 14:37:16 UTC
Applying a DEV_ACK for Eric Sandeen <firstname.lastname@example.org>. This bug was found by coverity and has a patch available.
Comment 10 Eric Sandeen 2007-07-02 20:43:17 UTC
In cvs as of e2fsprogs-1.35-12.7.el4
Comment 14 errata-xmlrpc 2007-11-15 16:01:32 UTC
An advisory has been issued which should help the problem described in this bug report. This report is therefore being closed with a resolution of ERRATA. For more information on the solution and/or where to find the updated files, please follow the link below. You may reopen this bug report if the solution does not work for you. http://rhn.redhat.com/errata/RHBA-2007-0758.html