strace crashed with SIGSEGV in __GI_raise()

[Till Kamppeter]

Happened when running

sudo strace /usr/sbin/cupsd -f

ProblemType: Crash
DistroRelease: Ubuntu 12.10
Package: strace 4.5.20-2.3ubuntu2
ProcVersionSignature: Ubuntu 3.5.0-16.25-generic 3.5.4
Uname: Linux 3.5.0-16-generic x86_64
ApportVersion: 2.6.1-0ubuntu1
Architecture: amd64
Date: Fri Oct 5 18:33:58 2012
ExecutablePath: /usr/bin/strace
InstallationMedia: Ubuntu 12.10 "Quantal Quetzal" - Alpha amd64 (20120724.2)
ProcCmdline: strace /usr/sbin/cupsd -f
ProcEnviron:
 TERM=xterm
 PATH=(custom, no user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
Signal: 11
SourcePackage: strace
StacktraceTop:
 __GI_raise (sig=<optimized out>) at ../nptl/sysdeps/unix/sysv/linux/raise.c:64
 ?? ()
 __libc_start_main (main=0x4020f0, argc=3, ubp_av=0x7fff38beb5e8, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7fff38beb5d8) at libc-start.c:226
 ?? ()
 ?? ()
Title: strace crashed with SIGSEGV in __GI_raise()
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups:

[Apport retracing service (apport)]

StacktraceSource:
 #0 0x00007f902bcb0425 in __GI_raise (sig=<optimized out>, sig@entry=11) at ../nptl/sysdeps/unix/sysv/linux/raise.c:64
   [Error: ../nptl/sysdeps/unix/sysv/linux/raise.c was not found in source tree]
 #1 0x0000000000402b9c in main (argc=<optimized out>, argv=<optimized out>) at ../strace.c:988
   [Error: ../strace.c was not found in source tree]
StacktraceTop:
 __GI_raise (sig=<optimized out>, sig@entry=11) at ../nptl/sysdeps/unix/sysv/linux/raise.c:64
 main (argc=<optimized out>, argv=<optimized out>) at ../strace.c:988

[Till Kamppeter (till-kamppeter)]

Note that the CUPS version which I had run under strace had a segfault bug, but this should not make strace crash.

This segfault in CUPS occured only during my development and not in any of the released CUPS packages, so I am not sure whether one can reproduce the bug with any available version of CUPS.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[yzp15 (yzp15)]

> Note that the CUPS version which I had run under strace had a segfault bug, but this should not make strace crash.

Actually, there is a code in strace.c (main -> terminate() ) to raise the signal which killed the traced process. Strace does it exactly before exit
https://github.com/strace/strace/blob/1d98b287a4cb6901d369d78126d481508f9e35ef/strace.c#L2655

 if (exit_code > 0xff) {
  ...
  /* Child was killed by a signal, mimic that. */
  exit_code &= 0xff;
  signal(exit_code, SIG_DFL);
  ...
  raise(exit_code);
 ...
 exit(exit_code);

Code was added in 2008-09-29 commit
https://github.com/strace/strace/commit/a68096576afc07e51d33b49c432d658b27a7f13c
> (main): Exit/kill ourself with straced child's exitcode/signal.

Same for other reports in https://errors.ubuntu.com/?package=strace&period=year like Bug #1430741