Description of problem:
/proc/sys/vm/mmap_min_addr isn't properly readable.

Version-Release number of selected component (if applicable):
2.6.32.11-99.fc12.x86_64

How reproducible:
Always

Steps to Reproduce:

$ ls -l /proc/sys/vm/mmap_min_addr 
-rw-r--r-- 1 root root 0 2010-04-15 09:55 /proc/sys/vm/mmap_min_addr
$ cat /proc/sys/vm/mmap_min_addr 
cat: /proc/sys/vm/mmap_min_addr: Operation not permitted

Excerpt from the strace of the cat process reveals:

open("/proc/sys/vm/mmap_min_addr", O_RDONLY) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=0, ...}) = 0
read(3, 0x60e000, 32768)                = -1 EPERM (Operation not permitted)

Note that the open succeeds, as would be expected by the
permissions indicated on the file.  But somehow the read
is actually failing.  The read succeeds as root.