1 files changed, 12 insertions, 2 deletions

diff --git a/arch/s390/kernel/signal.c b/arch/s390/kernel/signal.c
index c13a2a37ef00..d1259d875074 100644
--- a/arch/s390/kernel/signal.c
+++ b/arch/s390/kernel/signal.c
@@ -136,6 +136,10 @@ static int restore_sigregs(struct pt_regs *regs, _sigregs __user *sregs)
         /* Use regs->psw.mask instead of psw_user_bits to preserve PER bit. */
         regs->psw.mask = (regs->psw.mask & ~PSW_MASK_USER) |
                 (user_sregs.regs.psw.mask & PSW_MASK_USER);
+        /* Check for invalid user address space control. */
+        if ((regs->psw.mask & PSW_MASK_ASC) >= (psw_kernel_bits & PSW_MASK_ASC))
+                regs->psw.mask = (psw_user_bits & PSW_MASK_ASC) |
+                        (regs->psw.mask & ~PSW_MASK_ASC);
         /* Check for invalid amode */
         if (regs->psw.mask & PSW_MASK_EA)
                 regs->psw.mask |= PSW_MASK_BA;
@@ -273,7 +277,10 @@ static int setup_frame(int sig, struct k_sigaction *ka,
 
         /* Set up registers for signal handler */
         regs->gprs[15] = (unsigned long) frame;
-        regs->psw.mask |= PSW_MASK_EA | PSW_MASK_BA;    /* 64 bit amode */
+        /* Force default amode and default user address space control. */
+        regs->psw.mask = PSW_MASK_EA | PSW_MASK_BA |
+                (psw_user_bits & PSW_MASK_ASC) |
+                (regs->psw.mask & ~PSW_MASK_ASC);
         regs->psw.addr = (unsigned long) ka->sa.sa_handler | PSW_ADDR_AMODE;
 
         regs->gprs[2] = map_signal(sig);
@@ -346,7 +353,10 @@ static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
 
         /* Set up registers for signal handler */
         regs->gprs[15] = (unsigned long) frame;
-        regs->psw.mask |= PSW_MASK_EA | PSW_MASK_BA;    /* 64 bit amode */
+        /* Force default amode and default user address space control. */
+        regs->psw.mask = PSW_MASK_EA | PSW_MASK_BA |
+                (psw_user_bits & PSW_MASK_ASC) |
+                (regs->psw.mask & ~PSW_MASK_ASC);
         regs->psw.addr = (unsigned long) ka->sa.sa_handler | PSW_ADDR_AMODE;
 
         regs->gprs[2] = map_signal(sig);