reassign 652026 dpkg retitle 652026 start-stop-daemon: --name behaviour changes with kernel 3.1+ affects 652026 amavisd-new summary 652026 0 severity 652026 important thanks
On Thu, 15 Dec 2011, Michael Reincke wrote: > > Ok, so what broke perl/start-stop-daemon, now? --name uses > > /proc/<pid>/stat to locate the process... > > > > Might be the kernel, it seems to be failing on 3.1. > > > > Please give us the output of cat /proc/<pid of an amavis process>/stat, > > preferably for the master process (the one listed in the pid file). > > > the output as requested: > > <503 pcew80@reincke:~> ps -aef | grep amavis > amavis 2299 1 0 00:47 ? 00:00:01 amavisd (master) > amavis 2496 2299 0 00:47 ? 00:00:00 amavisd (ch7-avail) > amavis 2497 2299 0 00:47 ? 00:00:00 amavisd (ch7-avail) > amavis 2498 2299 0 00:47 ? 00:00:00 amavisd (ch6-avail) > reincke 7749 7078 0 08:32 pts/1 00:00:00 grep amavis > > <504 pcew80@reincke:~> cat /proc/2299/stat > 2299 (amavisd (master) S 1 2299 2299 0 -1 4202560 9771 0 4 0 119 5 0 > 0 20 0 1 0 22660083 221208576 22204 18446744073709551615 1 1 0 0 0 0 > 0 4224 81927 18446744073709551615 0 0 17 2 0 0 7 0 0 Crap. The kernel has done us in. Reassigning to dpkg to get some input on what should be done. Raising severity because it will cause some services to not be stopped or restarted properly, which has security implications. Guys, 3.1 changes /proc/<pid>/stat, and breaks anything using start-stop-daemon --name that also messes with the name of the process. Due to the chage in /proc/<pid>/stat, the executable name is not matched anymore. This probably affects only processes that change their "visible identity" (or whatever the string output by ps -aef is called) like amavisd-new does. Unfortunately, using --exec is not enough when you're dealing with perl, python or other scripts. How should we proceed? Drop use of start-stop-daemon --name in amavisd-new and document this kernel ABI issue in start-stop-daemon(8)? Reassign to the kernel on the grounds that it broke the userspace ABI? Enhance start-stop-daemon to take a --namere (regexp) and use that in amavisd-new instead? -- "One disk to rule them all, One disk to find them. One disk to bring them all and in the darkness grind them. In the Land of Redmond where the shadows lie." -- The Silicon Valley Tarot Henrique Holschuh -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org
