Red Hat Bugzilla – Bug 463734
Page ffffe000-fffff000 has invalid permissions
Last modified: 2012-06-20 12:09:13 EDT
Description of problem:
In bug 210779, comment #5 says that this page is mapped read-only for the kernel and not the user process and, later, points out that this entry does not appear in /proc/<pid>/maps for later releases. It would seem that the fix which crept into i386 when it shouldn't have.
Version-Release number of selected component (if applicable): 2.6.9-67.EL (for example)
How reproducible: always
Steps to Reproduce:
1. grep ^ffff /proc/self/maps
Observe that there is a map starting at ffffe000 and that it is, supposedly accessible.
Note that mprotect, for example, for an address in this range will return ENOMEN indicating that the page isn't accessible. Note also that this region is conspicuous by its absence on an RHEL5 machine.
The region should be marked inaccessible or not there at all.
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