CVS commit: src

["Kamil Rytarowski" <kamil%netbsd.org@localhost>]

Module Name:    src
Committed By:   kamil
Date:           Wed May 16 00:42:16 UTC 2018

Modified Files:
        src/sys/kern: kern_sig.c
        src/tests/lib/libc/sys: t_ptrace_wait.c

Log Message:
Correct handling of: vfork(2) + PT_TRACE_ME + raise(2)

Follow the FreeBSD approach of not routing signals to the parent that is
a became tracer after calling PT_TRACE_ME by the vfork(2)ed child (before
exec(3)/exit(3)).

Now if a child calls raise(3), the signal is processed directly to this
child.

Add new ATF ptrace(2) tests:
 - traceme_vfork_raise1 (SIGKILL)
 - traceme_vfork_raise2 (SIGSTOP) // temporarily disabled
 - traceme_vfork_raise3 (SIGABRT)
 - traceme_vfork_raise4 (SIGHUP)
 - traceme_vfork_raise5 (SIGCONT)

The FreeBSD implementation introduces P_PPTRACE for this special case.
Right know keep opencoding check of this case in the kernel. It might be
refactored in future.

The Linux kernel does not follow this approach and causes dead locking of
the processes (parent and child).

Defer handling SIGSTOP into future.

This is an intermediate step towards correct handling of fork(2) and
vfork(2) in the context of ptrace(2).

All new tests pass.
There are no regressions in existing ATF ptrace(2) tests.

Sponsored by <The NetBSD Foundation>


To generate a diff of this commit:
cvs rdiff -u -r1.343 -r1.344 src/sys/kern/kern_sig.c
cvs rdiff -u -r1.39 -r1.40 src/tests/lib/libc/sys/t_ptrace_wait.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.