CVS commit: src/sys/kern

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

Module Name:    src
Committed By:   kamil
Date:           Sun Apr  7 14:50:41 UTC 2019

Modified Files:
        src/sys/kern: kern_fork.c

Log Message:
Add a paranoid racy lock check in child_return()

In theory a child could be detached for some reason or another during
the time window between checking for PSL_TRACED and acquiring proc_lock.

Acquire the proc_lock mutex and recheck for PSL_TRACED before emitting
SIGTRAP. sigswitch() must acquite it internally anyway so this does not
have a negative impact and adds an extra sanity check.

For !PSL_TRACED case there is no impact.


To generate a diff of this commit:
cvs rdiff -u -r1.208 -r1.209 src/sys/kern/kern_fork.c

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