[Bug 212418] kernel panic in _taskqgroup_adjust - uninitialized variable

[bugzilla-noreply at freebsd.org]

https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=212418

            Bug ID: 212418
           Summary: kernel panic in _taskqgroup_adjust - uninitialized
                    variable
           Product: Base System
           Version: 11.0-STABLE
          Hardware: Any
                OS: Any
            Status: New
          Severity: Affects Many People
          Priority: ---
         Component: kern
          Assignee: freebsd-bugs at FreeBSD.org
          Reporter: shawn.webb at hardenedbsd.org

The variable qid in the fuunction _taskqgroup_adjust in
sys/kern/subr_gtaskqueue.c is used uninitialized in some instances. On my
Purism Librem 15, this variable is always unitialized.

I wrote a little patch to detect when it hasn't been set, but is being used
here:
https://github.com/HardenedBSD/hardenedBSD-playground/commit/7c3b5f7624459e8108873861442be5ce9f497ad7

100% of the time on the Librem 15 at bootup, qid will end up hitting the
KASSERT. I haven't studied the code to figure out a fix, yet. Without the
patch, though, the code in question will cause a write to an arbitrary
location, occasionally causing a kernel panic at bootup. With the patch, the
system is unbootable since qid is always -1.

-- 
You are receiving this mail because:
You are the assignee for the bug.