Bug 815065
| Summary: | CVE-2012-2133 kernel: use after free bug in "quota" handling | ||
|---|---|---|---|
| Product: | [Other] Security Response | Reporter: | Shachar Raindel <raindel> |
| Component: | vulnerability | Assignee: | Red Hat Product Security <security-response-team> |
| Status: | CLOSED DUPLICATE | QA Contact: | |
| Severity: | high | Docs Contact: | |
| Priority: | unspecified | ||
| Version: | unspecified | CC: | dledford, ogerlitz, security-response-team, yishaih |
| Target Milestone: | --- | Keywords: | Security |
| Target Release: | --- | ||
| Hardware: | All | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | Doc Type: | Bug Fix | |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2012-04-30 01:08:50 UTC | Type: | Bug |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
| Bug Depends On: | |||
| Bug Blocks: | 815174 | ||
Added CVE as per http://www.openwall.com/lists/oss-security/2012/04/24/12 I'm not sure why myself and Mellanox were added to this bug, but it is totally unrelated to code we take care of. Removing us from the Cc: list. *** This bug has been marked as a duplicate of bug 817430 *** |
Created attachment 579274 [details] Example code - will crash a machine running a debug kernel Description of problem: There is a use after free bug in the kernel hugetlb code. The bug can allow an authenticated, unprivileged local attacker to crash the system (and possibly gain higher privileges) if huge pages are enabled in the system. A fix has been committed to upstream, commit 90481622d75715bfcb68501280a917dbfe516029 "hugepages: fix use after free bug in "quota" handling" Version-Release number of selected component (if applicable): The bug exists in kernel versions 2.6.24 and above. How reproducible: The attached tarball includes an example code which utilizes a fuse mount with O_DIRECT flag to reproduce the issue. The code will work only on kernels 2.6.32 and above since it uses the new "anonymous mapping" API for getting huge pages. Similar reproduction is possible when using the shmem API or the hugetlbfs API. Stock kernel might not crash, debug kernel will detect the corruption and kill the process. Steps to Reproduce: 1. Untar the attached file 2. Run run_test.sh. The fuse-devel package and sudo rights are required for the fuse mount. Sudo rights are also required for enabling huge pages. 3. Observe the kernel crash when running debug kernel. Normal kernels will (usually) not crash, as the slab allocator will not return the memory blocks to the system general pool for a while. Actual results: A general protection fault message is printed, and the server is frozen. Expected results: The process should exit without the kernel crashing. Additional info: Verified on RHEL 6.0 with Dell PowerEdge 2950, should exist also on RHEL 6.2 and 6.1.