-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 Just pushed a fix into git. I had to re-implement realpath() to get it to work properly :(
Cheers, Simon. On 06/07/15 21:11, Toke Høiland-Jørgensen wrote: > I've hit this as well (but not the crash). > https://bugs.archlinux.org/task/45485 > > -Toke > > On 6 July 2015 20:04:13 CEST, Simon Kelley > <si...@thekelleys.org.uk> wrote: That works. The wrinkle is that > you have to replace /etc/resolv.conf with a dangling symlink, > rather than using --resolv-file to make dnsmasq look in some other > place where you put a dangling symlink, because the segfault comes > from writing to a constant string. > > Actually making this work with inotify, rather than generating an > error in this case, is more difficult. realpath() has unhelpful > semantics when there's a dangling symlink, and there doesn't seem > to be an equivalent that follows the the symlinks and tell you > where the last one points. > > Cheers, > > Simon. > > > On 06/07/15 14:24, Dave Reisner wrote: >>>> On Sun, Jul 05, 2015 at 10:44:24PM +0100, Simon Kelley wrote: >>>> This clearly a dnsmasq bug: it shouldn't segfault, but the >>>> description relies of lots of other "stuff" which makes it >>>> difficult to work out what systemd is doing to provoke the >>>> problem. It there a way to find out how systemd is invoking >>>> dnsmasq (ie the command-line) and how it differs between the >>>> systemd-resolved stopped and systemd-resolvd started? >>>> >>>> >>>> Cheers, >>>> >>>> Simon. >>>> >>>> >>>>> It should be simple enough to make /etc/resolv.conf a >>>>> symlink to nowhere, and start dnsmasq. Building from git, >>>>> it produces a crash where the top frame is: >>>> >>>>> #0 inotify_dnsmasq_init () at inotify.c:65 d = >>>>> 0x55555559b030 "/resolv.conf" path = 0x55555559b02c >>>>> "/etc/resolv.conf" res = 0x5555557ae428 >>>> >>>>> The likely reason /etc/resolv.conf is a symlink to nowhere >>>>> is because it points to /run/systemd/resolve/resolv.conf, >>>>> which is the real file with the resolver configuration. >>>>> Ideally, dnsmasq should wait for the symlink to point to a >>>>> regular file, or monitor the target of the symlink for >>>>> existence. As a stop-gap measure, users can add an 'After' >>>>> ordering on 'systemd-resolved.service' in dnsmasq.service. >>>>> I don't consider this to be a real solution because >>>>> systemd-resolved is just one instance of a daemon managing >>>>> a resolv.conf file on tmpfs, which /etc/resolv.conf could >>>>> point to. >>>> >>>>> HTH, Dave >>>> >>>> >>>> On 05/07/15 20:17, R wrote: >>>>>>> dnsmasq segfaults at boot and systemd fails to load >>>>>>> the service. ( http://sysv.se/journal.txt ) after the >>>>>>> boot process systemd can start dnsmasq successfully >>>>>>> through 'systemctl start dnsmasq' and everything >>>>>>> works. >>>>>>> >>>>>>> This started happening after I switched from using >>>>>>> netctl + dhcpcd to configure my interfaces to using >>>>>>> systemd-networkd + systemd-resolved. >>>>>>> >>>>>>> I was able to reproduce the segfault after the system >>>>>>> had started by stopping systemd-resolved. When >>>>>>> systemd-resolved was stopped, 'systemctl start dnsmasq' >>>>>>> again segfaulted. >>>>>>> >>>>>>> Starting systemd-resolved again, systemctl start >>>>>>> dnsmasq worked without problems. >>>>>>> >>>>>>> I'm using dnsmasq -> dnscrypt_proxy -> opendns on >>>>>>> latest Arch Linux fully updated as of the date of this >>>>>>> message. >>>>>>> >>>>>>> >>>>>>> >>>>>>> _______________________________________________ >>>>>>> Dnsmasq-discuss mailing list >>>>>>> Dnsmasq-discuss@lists.thekelleys.org.uk >>>>>>> http://lists.thekelleys.org.uk/mailman/listinfo/dnsmasq-discuss >>>>>>> >>>>> >>>>> >>>>>>> > >>>>>>> _______________________________________________ >>>>> Dnsmasq-discuss mailing list >>>>> Dnsmasq-discuss@lists.thekelleys.org.uk >>>>> http://lists.thekelleys.org.uk/mailman/listinfo/dnsmasq-discuss >>>> >> >> >>>>> _______________________________________________ >> Dnsmasq-discuss mailing list >> Dnsmasq-discuss@lists.thekelleys.org.uk >> http://lists.thekelleys.org.uk/mailman/listinfo/dnsmasq-discuss > > -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAEBCAAGBQJVmupKAAoJEBXN2mrhkTWiO3cQAKSZN+BV0yLpdS9mdAtdUPFK nibG30YyXkQLGi+ukextr71J4dJhwC+CyuH02T/7dYdEmSB0jxFGAHZoWKms9+Pr VkvBCmLrqh5yjJzEmA1j00EezuJnFaVjTN12iZnJuQP9qosyGT8X1fj9dvZ/AyQy 2hL5vm/YKRwXxqLGv5FYT8TLx2Z/+qhfWm05rPJIMmGg+x7BwItdnl7YWQGgpdOv sLlHFs19E6cdUr3ZwIDXN5RRw/GIEbTe3er1DQJj3Sj+Sx3VrE5DmHuNYDH5rmZB V03o81MhViPNSZ0gVxua/E1XQ1h3uLMCBrg1sy/q3ZH8jqWNqVdFPGimpo5cIE7z RkF8O/MaeNyvaEwi1w5hMU20cMKYQhoFhcBvE/07CI1KLFXtPdTN+wmeNS21SXYh hIaMkSgH9Nngo/+UHkhVgFpPLy+0WUu0xmls9HM2ENhuIrUObYFNViakxEOdMFvr bvy15abVnzb+rHom4w29fWFefNuN7w7cvWXKzWBPKKNe+YYSgjuQXVdHLUa7gPI+ qi8oSV2YTTuTLF69NKU99FALWcT/d+jLnU8rMvminQRpE6AsaycLBpUAbvUeGVZ1 6kvi1CiqCuzANcM55AY/TjXO2sZBr81/CnBA6FZ+fwqxvhZFq/H9fzyB6Qb7cnP/ ph7dK5CK6U3g4oJ1PBPW =YFmw -----END PGP SIGNATURE----- _______________________________________________ Dnsmasq-discuss mailing list Dnsmasq-discuss@lists.thekelleys.org.uk http://lists.thekelleys.org.uk/mailman/listinfo/dnsmasq-discuss
