kern/60754: kern: potential syscall argument package stack garbage

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>Number:         60754
>Category:       kern
>Synopsis:       kern: potential syscall argument package stack garbage
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sun Sep 20 12:30:01 +0000 2026
>Originator:     Taylor R Campbell
>Release:        current, 11, 10, ...
>Organization:
The NetBSD Syscaller, Inc.
>Environment:
>Description:

	Various functions -- mostly in compat_* -- are defined by
	creating syscall argument packages and invoking the syscall
	entry point:

		struct sys_foo_args ua;

		SCARG(&ua, x) = 42;
		SCARG(&ua, y) = pqr;

		sys_foo(l, &ua, retval);

	There have been some bugs with missing parameters that instead
	receive stack garbage.  We should systematically zero these
	argument packages.

>How-To-Repeat:

	code inspection

>Fix:

	memset(&ua, 0, sizeof(ua));