[S390] uaccess error handling.

Consider return values for all user space access function and
return -EFAULT on error.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 13 insertions, 7 deletions

diff --git a/arch/s390/kernel/traps.c b/arch/s390/kernel/traps.c
index 66375a5e3d12..92ecffbc8d82 100644
--- a/arch/s390/kernel/traps.c
+++ b/arch/s390/kernel/traps.c
@@ -462,7 +462,8 @@ asmlinkage void illegal_op(struct pt_regs * regs, long interruption_code)
                 local_irq_enable();
 
         if (regs->psw.mask & PSW_MASK_PSTATE) {
-                get_user(*((__u16 *) opcode), (__u16 __user *) location);
+                if (get_user(*((__u16 *) opcode), (__u16 __user *) location))
+                        return;
                 if (*((__u16 *) opcode) == S390_BREAKPOINT_U16) {
                         if (current->ptrace & PT_PTRACED)
                                 force_sig(SIGTRAP, current);
@@ -470,20 +471,25 @@ asmlinkage void illegal_op(struct pt_regs * regs, long interruption_code)
                                 signal = SIGILL;
 #ifdef CONFIG_MATHEMU
                 } else if (opcode[0] == 0xb3) {
-                        get_user(*((__u16 *) (opcode+2)), location+1);
+                        if (get_user(*((__u16 *) (opcode+2)), location+1))
+                                return;
                         signal = math_emu_b3(opcode, regs);
                 } else if (opcode[0] == 0xed) {
-                        get_user(*((__u32 *) (opcode+2)),
-                                 (__u32 __user *)(location+1));
+                        if (get_user(*((__u32 *) (opcode+2)),
+                                     (__u32 __user *)(location+1)))
+                                return;
                         signal = math_emu_ed(opcode, regs);
                 } else if (*((__u16 *) opcode) == 0xb299) {
-                        get_user(*((__u16 *) (opcode+2)), location+1);
+                        if (get_user(*((__u16 *) (opcode+2)), location+1))
+                                return;
                         signal = math_emu_srnm(opcode, regs);
                 } else if (*((__u16 *) opcode) == 0xb29c) {
-                        get_user(*((__u16 *) (opcode+2)), location+1);
+                        if (get_user(*((__u16 *) (opcode+2)), location+1))
+                                return;
                         signal = math_emu_stfpc(opcode, regs);
                 } else if (*((__u16 *) opcode) == 0xb29d) {
-                        get_user(*((__u16 *) (opcode+2)), location+1);
+                        if (get_user(*((__u16 *) (opcode+2)), location+1))
+                                return;
                         signal = math_emu_lfpc(opcode, regs);
 #endif
                 } else