On Wed, Oct 4, 2017 at 12:13 PM, Jann Horn <ja...@google.com> wrote:
>
> Actually, /proc/kallsyms uses %pK, which hacks around this issue
> by checking for `euid != uid` in addition to the capability check - so this
> isn't exploitable through a typical setuid program.
Fair enough, you'd have to be a pretty broken suid program to have set
uid to euid before reading some untrusted file descriptor.
I could still imagine happening (hey, the X server used to sendmsg
file descriptors back and forth), but hopefully it's not really
realistic.
Linus
