signal/sparc32: In setup_rt_frame and setup_fram use force_fatal_sig

Modify the 32bit version of setup_rt_frame and setup_frame to act
similar to the 64bit version of setup_rt_frame and fail with a signal
instead of calling do_exit.

Replacing do_exit(SIGILL) with force_fatal_signal(SIGILL) ensures that
the process will be terminated cleanly when the stack frame is
invalid, instead of just killing off a single thread and leaving the
process is a weird state.

Cc: David Miller <davem@davemloft.net>
Cc: sparclinux@vger.kernel.org
Link: https://lkml.kernel.org/r/20211020174406.17889-16-ebiederm@xmission.comSigned-off-by: Eric W. Biederman <ebiederm@xmission.com>

arch/sparc/kernel/signal_32.c

@@ -244,7 +244,7 @@ static int setup_frame(struct ksignal *ksig, struct pt_regs *regs,
 		get_sigframe(ksig, regs, sigframe_size);
 
 	if (invalid_frame_pointer(sf, sigframe_size)) {
-		do_exit(SIGILL);
+		force_fatal_sig(SIGILL);
 		return -EINVAL;
 	}
 
@@ -336,7 +336,7 @@ static int setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs,
 	sf = (struct rt_signal_frame __user *)
 		get_sigframe(ksig, regs, sigframe_size);
 	if (invalid_frame_pointer(sf, sigframe_size)) {
-		do_exit(SIGILL);
+		force_fatal_sig(SIGILL);
 		return -EINVAL;
 	}