OracleVM 3.1 : xen (OVMSA-2014-0002)
Medium Nessus Plugin ID 79530
SynopsisThe remote OracleVM host is missing one or more security updates.
DescriptionThe remote OracleVM system is missing necessary patches to address critical security updates :
- flask: restrict allocations done by hypercall interface Other than in 4.2 and newer, we're not having an overflow issue here, but uncontrolled exposure of the operations opens the host to be driven out of memory by an arbitrary guest. Since all operations other than FLASK_LOAD simply deal with ASCII strings, limiting the allocations (and incoming buffer sizes) to a page worth of memory seems like the best thing we can do.
Consequently, in order to not expose the larger allocation to arbitrary guests, the permission check for FLASK_LOAD needs to be pulled ahead of the allocation (and it's perhaps worth noting that - afaict - it was pointlessly done with the sel_sem spin lock held). Note that this breaks FLASK_AVC_CACHESTATS on systems with sufficiently many CPUs (as requiring a buffer bigger than PAGE_SIZE there). No attempt is made to address this here, as it would needlessly complicate this fix with rather little gain. This is XSA-84.
The index of boolean variables in FLASK_[GET,SET]BOOL was not always checked against the bounds of the array.
18205387] (CVE-2014-1892, CVE-2014-1893)
- libxc: Fix out-of-memory error handling in xc_cpupool_getinfo Avoid freeing info then returning it to the caller. This is XSA-88. Coverity-ID: 1056192
SolutionUpdate the affected xen / xen-devel / xen-tools packages.