[ARM] 2959/1: Add test for invalid LDRD/STRD Rd cases in ARM alignment handler

Patch from George G. Davis

Add test for invalid LDRD/STRD Rd cases in ARM alignment handler
and restore SWP printk KERN_ERR.

Signed-off-by: Steve Longerbeam <[e-mail]>
Signed-off-by: George G. Davis <[e-mail]>
Signed-off-by: Russell King <[e-mail]>

arch/arm/mm/alignment.c

···
 {
 	unsigned int rd = RD_BITS(instr);
 
+	if (((rd & 1) == 1) || (rd == 14))
+		goto bad;
+
 	ai_dword += 1;
 
 	if (user_mode(regs))
···
 	}
 
 	return TYPE_LDST;
-
+ bad:
+	return TYPE_ERROR;
  fault:
 	return TYPE_FAULT;
 }
···
 		else if ((instr & 0x001000f0) == 0x000000d0 || /* LDRD */
 			 (instr & 0x001000f0) == 0x000000f0)   /* STRD */
 			handler = do_alignment_ldrdstrd;
+		else if ((instr & 0x01f00ff0) == 0x01000090) /* SWP */
+			goto swp;
 		else
 			goto bad;
 		break;
···
 	 */
 	do_bad_area(current, current->mm, addr, fsr, regs);
 	return 0;
+
+ swp:
+	printk(KERN_ERR "Alignment trap: not handling swp instruction\n");
 
  bad:
 	/*