Description of problem: Running gdb or readelf on a coredump file gives the following output: "/var/tmp/coredump-6H6at9" is not a core dump: File format not recognized I'll attach readelf output later on. The size of the corefile is plausible, and the ELF headers are there, so it's not totally bonkers, just somehow corrupted. Version-Release number of selected component (if applicable): kernel-4.7.0-0.rc0.git4.1.fc25.x86_64 is first bad kernel-4.7.0-0.rc0.git3.1.fc25.x86_64 is last good How reproducible: 100% Steps to Reproduce: 1. sudo sysctl -w kernel.core_pattern='|/bin/tee /var/tmp/core.%p' 2. bash -c 'kill -SEGV $$' 3. gdb /var/tmp/core.XXX Note that using kernel.core_pattern without "|", i.e. dumping directly to a file, works.
Created attachment 1164631 [details] readelf output for bash core file, kernel 4.7.0-0.rc0.git4.1.fc25.x86_64
Thanks for a nice bugreport. I posted a fix here: http://marc.info/?l=linux-kernel&m=146512775611208&w=2
Let me know when the patch gets Acked/Accpeted and I'll pull it into rawhide.
The patch came in in today's rawhide. I didn't realize that before I posted my comment. Closing the bug now.