Red Hat Bugzilla – Bug 441406
ptrace: Stepping out of a signal handler runs away
Last modified: 2008-07-22 18:50:04 EDT
Description of problem:
On repeated PTRACE_SINGLESTEP when a signal gets delivered the signal handler
gets traced but on the `int 0x80' of `__kernel_sigreturn' it starts to
Version-Release number of selected component (if applicable):
FAILs kernel-2.6.25-0.195.rc8.git1.fc9.i686 patched by
PASSes kernel-2.6.20-1.2933.fc6.i686 (as reported by mwielaard)
Steps to Reproduce:
wget -O step-through-sigret.c
gcc -o step-through-sigret step-through-sigret.c -Wall -ggdb2 -D_GNU_SOURCE;
./step-through-sigret; echo $?
From Wenji Huang
"Verified that the test couldn't pass on > 2.6.20 i686 kernel [...]
But passed on >= 2.6.22 (vanilla, x86_64) and 2.6.25 (utrace patched, x86_64)"
So it seems to not be utrace specific, but an upstream ptrace/signal bug since
2.6.21 on x86 only.
->ptrace as the Bug is not utrace-related:
I have the same problem on Fedora 9 with gcc : gcc-4.3.0-8.i386,
glibc-headers-2.8-3.i386 (same version of glibc of course)
I downloaded the script given above and I also obtain
This is probably related to my difficulties starting user-mode-linux kernels
from: <http://user-mode-linux.sourceforge.net/> or
Thanks, verified as fixed on kernel-22.214.171.124-47.fc8.x86_64.