Checkpoint a hack to enable running i386 libc_r binaries on a 64 bit

kernel.  I'm not happy with it yet - refinements are to come.
This hack allows the kern.ps_strings and kern.usrstack sysctls to respond
to a 32 bit request, such as those coming from emulated i386 binaries.

1 files changed, 22 insertions, 4 deletions

diff --git a/sys/kern/kern_exec.c b/sys/kern/kern_exec.c
index 6e3d86e..4d2a7fe 100644
--- a/sys/kern/kern_exec.c
+++ b/sys/kern/kern_exec.c
@@ -102,20 +102,38 @@ static int
 sysctl_kern_ps_strings(SYSCTL_HANDLER_ARGS)
 {
 	struct proc *p;
+	int error;
 
 	p = curproc;
-	return (SYSCTL_OUT(req, &p->p_sysent->sv_psstrings,
-	   sizeof(p->p_sysent->sv_psstrings)));
+#if defined(__amd64__) || defined(__ia64__)
+	if (req->oldlen == sizeof(unsigned int)) {
+		unsigned int val;
+		val = (unsigned int)p->p_sysent->sv_psstrings;
+		error = SYSCTL_OUT(req, &val, sizeof(val));
+	} else
+#endif
+		error = SYSCTL_OUT(req, &p->p_sysent->sv_psstrings,
+		   sizeof(p->p_sysent->sv_psstrings));
+	return error;
 }
 
 static int
 sysctl_kern_usrstack(SYSCTL_HANDLER_ARGS)
 {
 	struct proc *p;
+	int error;
 
 	p = curproc;
-	return (SYSCTL_OUT(req, &p->p_sysent->sv_usrstack,
-	    sizeof(p->p_sysent->sv_usrstack)));
+#if defined(__amd64__) || defined(__ia64__)
+	if (req->oldlen == sizeof(unsigned int)) {
+		unsigned int val;
+		val = (unsigned int)p->p_sysent->sv_usrstack;
+		error = SYSCTL_OUT(req, &val, sizeof(val));
+	} else
+#endif
+		error = SYSCTL_OUT(req, &p->p_sysent->sv_usrstack,
+		    sizeof(p->p_sysent->sv_usrstack));
+	return error;
 }
 
 static int