On Fri, Jan 13, 2023 at 03:21:36PM +0100, Thomas Liske wrote:
Signed-off-by: Thomas Liske <liske@ibh.de> ---
This patch sets the PR_SET_DUMPABLE capability before switching to a unprivileged user to allow core dumps (see also the paragraph about set-user-ID in `man 5 core`)
Background: While debugging bird on Alpine we wonder why it was not possible to get a core dump when bird runs under a unprivileged user.
Hi Sorry for later reply. Did not know about this issue with core dumps. It is interesting nobody noticed that before. I am not really sure why using setresuid() has the same core dump restriction as set-user-ID programs, considering it changes both real and effective UID. Using prctl(PR_SET_DUMPABLE) has some strange side-effects in changing ownership of /proc/<pid>/* fields. Not really sure what are implications of that. -- Elen sila lumenn' omentielvo Ondrej 'Santiago' Zajicek (email: santiago@crfreenet.org) OpenPGP encrypted e-mails preferred (KeyID 0x11DEADC3, wwwkeys.pgp.net) "To err is human -- to blame it on a computer is even more so."