[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>

4 files changed, 28 insertions, 20 deletions

diff --git a/arch/s390/kernel/compat_linux.c b/arch/s390/kernel/compat_linux.c
index 2001767e1dc7..5b33f823863a 100644
--- a/arch/s390/kernel/compat_linux.c
+++ b/arch/s390/kernel/compat_linux.c
@@ -757,7 +757,9 @@ asmlinkage long sys32_sysctl(struct __sysctl_args32 __user *args)
                             put_user(oldlen, (u32 __user *)compat_ptr(tmp.oldlenp)))
                                 error = -EFAULT;
                 }
-                copy_to_user(args->__unused, tmp.__unused, sizeof(tmp.__unused));
+                if (copy_to_user(args->__unused, tmp.__unused,
+                                 sizeof(tmp.__unused)))
+                        error = -EFAULT;
         }
         return error;
 }
diff --git a/arch/s390/kernel/compat_signal.c b/arch/s390/kernel/compat_signal.c
index d49b876a83bf..861888ab8c13 100644
--- a/arch/s390/kernel/compat_signal.c
+++ b/arch/s390/kernel/compat_signal.c
@@ -169,12 +169,12 @@ sys32_sigaction(int sig, const struct old_sigaction32 __user *act,
                 compat_old_sigset_t mask;
                 if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
                     __get_user(sa_handler, &act->sa_handler) ||
-                    __get_user(sa_restorer, &act->sa_restorer))
+                    __get_user(sa_restorer, &act->sa_restorer) ||
+                    __get_user(new_ka.sa.sa_flags, &act->sa_flags) ||
+                    __get_user(mask, &act->sa_mask))
                         return -EFAULT;
                 new_ka.sa.sa_handler = (__sighandler_t) sa_handler;
                 new_ka.sa.sa_restorer = (void (*)(void)) sa_restorer;
-                __get_user(new_ka.sa.sa_flags, &act->sa_flags);
-                __get_user(mask, &act->sa_mask);
                 siginitset(&new_ka.sa.sa_mask, mask);
         }
 
@@ -185,10 +185,10 @@ sys32_sigaction(int sig, const struct old_sigaction32 __user *act,
                 sa_restorer = (unsigned long) old_ka.sa.sa_restorer;
                 if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
                     __put_user(sa_handler, &oact->sa_handler) ||
-                    __put_user(sa_restorer, &oact->sa_restorer))
+                    __put_user(sa_restorer, &oact->sa_restorer) ||
+                    __put_user(old_ka.sa.sa_flags, &oact->sa_flags) ||
+                    __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask))
                         return -EFAULT;
-                __put_user(old_ka.sa.sa_flags, &oact->sa_flags);
-                __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask);
         }
 
         return ret;
diff --git a/arch/s390/kernel/signal.c b/arch/s390/kernel/signal.c
index 4392a77cbae8..4c8a7954ef48 100644
--- a/arch/s390/kernel/signal.c
+++ b/arch/s390/kernel/signal.c
@@ -80,10 +80,10 @@ sys_sigaction(int sig, const struct old_sigaction __user *act,
                 old_sigset_t mask;
                 if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
                     __get_user(new_ka.sa.sa_handler, &act->sa_handler) ||
-                    __get_user(new_ka.sa.sa_restorer, &act->sa_restorer))
+                    __get_user(new_ka.sa.sa_restorer, &act->sa_restorer) ||
+                    __get_user(new_ka.sa.sa_flags, &act->sa_flags) ||
+                    __get_user(mask, &act->sa_mask))
                         return -EFAULT;
-                __get_user(new_ka.sa.sa_flags, &act->sa_flags);
-                __get_user(mask, &act->sa_mask);
                 siginitset(&new_ka.sa.sa_mask, mask);
         }
 
@@ -92,10 +92,10 @@ sys_sigaction(int sig, const struct old_sigaction __user *act,
         if (!ret && oact) {
                 if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
                     __put_user(old_ka.sa.sa_handler, &oact->sa_handler) ||
-                    __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer))
+                    __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer) ||
+                    __put_user(old_ka.sa.sa_flags, &oact->sa_flags) ||
+                    __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask))
                         return -EFAULT;
-                __put_user(old_ka.sa.sa_flags, &oact->sa_flags);
-                __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask);
         }
 
         return ret;
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