diff options
Diffstat (limited to 'arch/s390/kernel/signal.c')
| -rw-r--r-- | arch/s390/kernel/signal.c | 14 |
1 files changed, 10 insertions, 4 deletions
diff --git a/arch/s390/kernel/signal.c b/arch/s390/kernel/signal.c index c19755815e53..05a85bc14c98 100644 --- a/arch/s390/kernel/signal.c +++ b/arch/s390/kernel/signal.c @@ -117,8 +117,8 @@ static int save_sigregs(struct pt_regs *regs, _sigregs __user *sregs) /* Copy a 'clean' PSW mask to the user to avoid leaking information about whether PER is currently on. */ - user_sregs.regs.psw.mask = psw_user_bits | PSW_MASK_EA | PSW_MASK_BA | - (regs->psw.mask & PSW_MASK_USER); + user_sregs.regs.psw.mask = psw_user_bits | + (regs->psw.mask & PSW_MASK_USER); user_sregs.regs.psw.addr = regs->psw.addr; memcpy(&user_sregs.regs.gprs, ®s->gprs, sizeof(sregs->regs.gprs)); memcpy(&user_sregs.regs.acrs, current->thread.acrs, @@ -145,9 +145,13 @@ static int restore_sigregs(struct pt_regs *regs, _sigregs __user *sregs) err = __copy_from_user(&user_sregs, sregs, sizeof(_sigregs)); if (err) return err; + /* 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); - regs->psw.addr = PSW_ADDR_AMODE | user_sregs.regs.psw.addr; + (user_sregs.regs.psw.mask & PSW_MASK_USER); + /* Check for invalid amode */ + if (regs->psw.mask & PSW_MASK_EA) + regs->psw.mask |= PSW_MASK_BA; + regs->psw.addr = user_sregs.regs.psw.addr; memcpy(®s->gprs, &user_sregs.regs.gprs, sizeof(sregs->regs.gprs)); memcpy(¤t->thread.acrs, &user_sregs.regs.acrs, sizeof(sregs->regs.acrs)); @@ -290,6 +294,7 @@ 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 */ regs->psw.addr = (unsigned long) ka->sa.sa_handler | PSW_ADDR_AMODE; regs->gprs[2] = map_signal(sig); @@ -358,6 +363,7 @@ 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 */ regs->psw.addr = (unsigned long) ka->sa.sa_handler | PSW_ADDR_AMODE; regs->gprs[2] = map_signal(sig); |