Package: dpkg Version: 1.8.0 Severity: critical The new buffer_read(), buffer_copy(), etc. family of functions in dpkg (lib/mlib.c) interact nastily with a bug in Linux 2.2 kernels before 2.2.11, in which kernel version that bug was reportedly fixed. The symptoms are that, while unpacking, dpkg gets EAGAIN while reading from its pipe to dpkg-deb, and promptly segfaults. As best as I can tell, this happens with all packages, and I had to unpack dpkg manually in the root directory to recover. Further details of the symptoms are in the debian-dpkg thread starting at http://lists.debian.org/debian-dpkg-0101/msg00016.html, and a full strace of the dpkg session is at http://www.chiark.greenend.org.uk/~cjwatson/dpkg-strace. While at that point I'd only seen the problem in 2.2.5, somebody else mailed me privately saying he'd had the same problems with 2.2.10.
http://www.tux.org/hypermail/linux-kernel/1999week24/0199.html is almost certainly relevant here; apparently, zero-length reads on non-empty pipes incorrectly returned -1 and EAGAIN instead of the correct 0. I notice from the strace (near the end) that dpkg is trying to do a read() of length 0; perhaps this read should be suppressed? http://www.linux.org.uk/VERSION/relnotes.2211.html reports the following change in Linux 2.2.11: Pipes A technical violation of the SuSv2 specification when preading 0 bytes from a pipe has been fixed. ... so you should be able to reproduce this in any 2.2 kernel before that. HTH, -- Colin Watson [EMAIL PROTECTED]
