• Kees Cook's avatar
    proc: protect mm start_code/end_code in /proc/pid/stat · 5883f57c
    Kees Cook authored
    While mm->start_stack was protected from cross-uid viewing (commit
    f83ce3e6 ("proc: avoid information leaks to non-privileged
    processes")), the start_code and end_code values were not.  This would
    allow the text location of a PIE binary to leak, defeating ASLR.
    
    Note that the value "1" is used instead of "0" for a protected value since
    "ps", "killall", and likely other readers of /proc/pid/stat, take
    start_code of "0" to mean a kernel thread and will misbehave.  Thanks to
    Brad Spengler for pointing this out.
    
    Addresses CVE-2011-0726
    Signed-off-by: default avatarKees Cook <kees.cook@canonical.com>
    Cc: <stable@kernel.org>
    Cc: Alexey Dobriyan <adobriyan@gmail.com>
    Cc: David Howells <dhowells@redhat.com>
    Cc: Eugene Teo <eugeneteo@kernel.sg>
    Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
    Cc: Brad Spengler <spender@grsecurity.net>
    Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
    Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
    5883f57c
array.c 13.2 KB