Re: A problem with prctl(2) and proc(5)

["Michael Kerrisk (man-pages)" <mtk.manpages@gmail.com>]

Hello Eric,

On Tue, 24 Oct 2017 at 00:47, Eric Hopper <hopper@omnifarious.org> wrote:
>
> Also... execve(2) should make a passing mention of the DUMPABLE flag
> and point at the prctl documentation where it talks about set-user-ID
> processes. That would've greatly shortened my search for the answer I
> needed.

I added some sentences to the execve(2) page, so that tehre is now a
piece that reads:

       *  The  process's  "dumpable"  attribute  is  set  to the value 1,
          unless a set-user-ID program, a set-group-ID program, or a pro‐
          gram  with  capabilities  is  being executed, in which case the
          dumpable  flag  may  instead  be  reset   to   the   value   in
          /proc/sys/fs/suid_dumpable,   in  the  circumstances  described
          under PR_SET_DUMPABLE in prctl(2).  Note that  changes  to  the
          "dumpable"  attribute  may  cause  ownership  of  files  in the
          process's /proc/[pid] directory  to  change  to  root:root,  as
          described in proc(5).

Thanks,

Michael

-- 
Michael Kerrisk
Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/
Linux/UNIX System Programming Training: http://man7.org/training/