--- zzzz-none-000/linux-3.10.107/arch/s390/kernel/signal.c 2017-06-27 09:49:32.000000000 +0000 +++ scorpion-7490-727/linux-3.10.107/arch/s390/kernel/signal.c 2021-02-04 17:41:59.000000000 +0000 @@ -31,66 +31,131 @@ #include #include "entry.h" -typedef struct +/* + * Layout of an old-style signal-frame: + * ----------------------------------------- + * | save area (_SIGNAL_FRAMESIZE) | + * ----------------------------------------- + * | struct sigcontext | + * | oldmask | + * | _sigregs * | + * ----------------------------------------- + * | _sigregs with | + * | _s390_regs_common | + * | _s390_fp_regs | + * ----------------------------------------- + * | int signo | + * ----------------------------------------- + * | _sigregs_ext with | + * | gprs_high 64 byte (opt) | + * | vxrs_low 128 byte (opt) | + * | vxrs_high 256 byte (opt) | + * | reserved 128 byte (opt) | + * ----------------------------------------- + * | __u16 svc_insn | + * ----------------------------------------- + * The svc_insn entry with the sigreturn system call opcode does not + * have a fixed position and moves if gprs_high or vxrs exist. + * Future extensions will be added to _sigregs_ext. + */ +struct sigframe { __u8 callee_used_stack[__SIGNAL_FRAMESIZE]; struct sigcontext sc; _sigregs sregs; int signo; - __u8 retcode[S390_SYSCALL_SIZE]; -} sigframe; + _sigregs_ext sregs_ext; + __u16 svc_insn; /* Offset of svc_insn is NOT fixed! */ +}; -typedef struct +/* + * Layout of an rt signal-frame: + * ----------------------------------------- + * | save area (_SIGNAL_FRAMESIZE) | + * ----------------------------------------- + * | svc __NR_rt_sigreturn 2 byte | + * ----------------------------------------- + * | struct siginfo | + * ----------------------------------------- + * | struct ucontext_extended with | + * | unsigned long uc_flags | + * | struct ucontext *uc_link | + * | stack_t uc_stack | + * | _sigregs uc_mcontext with | + * | _s390_regs_common | + * | _s390_fp_regs | + * | sigset_t uc_sigmask | + * | _sigregs_ext uc_mcontext_ext | + * | gprs_high 64 byte (opt) | + * | vxrs_low 128 byte (opt) | + * | vxrs_high 256 byte (opt)| + * | reserved 128 byte (opt) | + * ----------------------------------------- + * Future extensions will be added to _sigregs_ext. + */ +struct rt_sigframe { __u8 callee_used_stack[__SIGNAL_FRAMESIZE]; - __u8 retcode[S390_SYSCALL_SIZE]; + __u16 svc_insn; struct siginfo info; - struct ucontext uc; -} rt_sigframe; + struct ucontext_extended uc; +}; + +/* Store registers needed to create the signal frame */ +static void store_sigregs(void) +{ + save_access_regs(current->thread.acrs); + save_fpu_regs(); +} + +/* Load registers after signal return */ +static void load_sigregs(void) +{ + restore_access_regs(current->thread.acrs); +} /* Returns non-zero on fault. */ static int save_sigregs(struct pt_regs *regs, _sigregs __user *sregs) { _sigregs user_sregs; - save_access_regs(current->thread.acrs); - /* 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 | - (regs->psw.mask & PSW_MASK_USER); + user_sregs.regs.psw.mask = PSW_USER_BITS | + (regs->psw.mask & (PSW_MASK_USER | PSW_MASK_RI)); 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, - sizeof(sregs->regs.acrs)); - /* - * We have to store the fp registers to current->thread.fp_regs - * to merge them with the emulated registers. - */ - save_fp_regs(¤t->thread.fp_regs); - memcpy(&user_sregs.fpregs, ¤t->thread.fp_regs, - sizeof(s390_fp_regs)); - return __copy_to_user(sregs, &user_sregs, sizeof(_sigregs)); + sizeof(user_sregs.regs.acrs)); + fpregs_store(&user_sregs.fpregs, ¤t->thread.fpu); + if (__copy_to_user(sregs, &user_sregs, sizeof(_sigregs))) + return -EFAULT; + return 0; } -/* Returns positive number on error */ static int restore_sigregs(struct pt_regs *regs, _sigregs __user *sregs) { - int err; _sigregs user_sregs; /* Alwys make any pending restarted system call return -EINTR */ - current_thread_info()->restart_block.fn = do_no_restart_syscall; + current->restart_block.fn = do_no_restart_syscall; + + if (__copy_from_user(&user_sregs, sregs, sizeof(user_sregs))) + return -EFAULT; + + if (!is_ri_task(current) && (user_sregs.regs.psw.mask & PSW_MASK_RI)) + return -EINVAL; - 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); + /* Test the floating-point-control word. */ + if (test_fp_ctl(user_sregs.fpregs.fpc)) + return -EINVAL; + + /* Use regs->psw.mask instead of PSW_USER_BITS to preserve PER bit. */ + regs->psw.mask = (regs->psw.mask & ~(PSW_MASK_USER | PSW_MASK_RI)) | + (user_sregs.regs.psw.mask & (PSW_MASK_USER | PSW_MASK_RI)); /* 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) | + if ((regs->psw.mask & PSW_MASK_ASC) == PSW_ASC_HOME) + regs->psw.mask = PSW_ASC_PRIMARY | (regs->psw.mask & ~PSW_MASK_ASC); /* Check for invalid amode */ if (regs->psw.mask & PSW_MASK_EA) @@ -98,29 +163,71 @@ 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)); - restore_access_regs(current->thread.acrs); + sizeof(current->thread.acrs)); - memcpy(¤t->thread.fp_regs, &user_sregs.fpregs, - sizeof(s390_fp_regs)); - current->thread.fp_regs.fpc &= FPC_VALID_MASK; + fpregs_load(&user_sregs.fpregs, ¤t->thread.fpu); - restore_fp_regs(¤t->thread.fp_regs); - clear_thread_flag(TIF_SYSCALL); /* No longer in a system call */ + clear_pt_regs_flag(regs, PIF_SYSCALL); /* No longer in a system call */ + return 0; +} + +/* Returns non-zero on fault. */ +static int save_sigregs_ext(struct pt_regs *regs, + _sigregs_ext __user *sregs_ext) +{ + __u64 vxrs[__NUM_VXRS_LOW]; + int i; + + /* Save vector registers to signal stack */ + if (MACHINE_HAS_VX) { + for (i = 0; i < __NUM_VXRS_LOW; i++) + vxrs[i] = *((__u64 *)(current->thread.fpu.vxrs + i) + 1); + if (__copy_to_user(&sregs_ext->vxrs_low, vxrs, + sizeof(sregs_ext->vxrs_low)) || + __copy_to_user(&sregs_ext->vxrs_high, + current->thread.fpu.vxrs + __NUM_VXRS_LOW, + sizeof(sregs_ext->vxrs_high))) + return -EFAULT; + } + return 0; +} + +static int restore_sigregs_ext(struct pt_regs *regs, + _sigregs_ext __user *sregs_ext) +{ + __u64 vxrs[__NUM_VXRS_LOW]; + int i; + + /* Restore vector registers from signal stack */ + if (MACHINE_HAS_VX) { + if (__copy_from_user(vxrs, &sregs_ext->vxrs_low, + sizeof(sregs_ext->vxrs_low)) || + __copy_from_user(current->thread.fpu.vxrs + __NUM_VXRS_LOW, + &sregs_ext->vxrs_high, + sizeof(sregs_ext->vxrs_high))) + return -EFAULT; + for (i = 0; i < __NUM_VXRS_LOW; i++) + *((__u64 *)(current->thread.fpu.vxrs + i) + 1) = vxrs[i]; + } return 0; } SYSCALL_DEFINE0(sigreturn) { struct pt_regs *regs = task_pt_regs(current); - sigframe __user *frame = (sigframe __user *)regs->gprs[15]; + struct sigframe __user *frame = + (struct sigframe __user *) regs->gprs[15]; sigset_t set; if (__copy_from_user(&set.sig, &frame->sc.oldmask, _SIGMASK_COPY_SIZE)) goto badframe; set_current_blocked(&set); + save_fpu_regs(); if (restore_sigregs(regs, &frame->sregs)) goto badframe; + if (restore_sigregs_ext(regs, &frame->sregs_ext)) + goto badframe; + load_sigregs(); return regs->gprs[2]; badframe: force_sig(SIGSEGV, current); @@ -130,16 +237,21 @@ SYSCALL_DEFINE0(rt_sigreturn) { struct pt_regs *regs = task_pt_regs(current); - rt_sigframe __user *frame = (rt_sigframe __user *)regs->gprs[15]; + struct rt_sigframe __user *frame = + (struct rt_sigframe __user *)regs->gprs[15]; sigset_t set; if (__copy_from_user(&set.sig, &frame->uc.uc_sigmask, sizeof(set))) goto badframe; set_current_blocked(&set); + if (restore_altstack(&frame->uc.uc_stack)) + goto badframe; + save_fpu_regs(); if (restore_sigregs(regs, &frame->uc.uc_mcontext)) goto badframe; - if (restore_altstack(&frame->uc.uc_stack)) + if (restore_sigregs_ext(regs, &frame->uc.uc_mcontext_ext)) goto badframe; + load_sigregs(); return regs->gprs[2]; badframe: force_sig(SIGSEGV, current); @@ -147,11 +259,6 @@ } /* - * Set up a signal frame. - */ - - -/* * Determine which stack to use.. */ static inline void __user * @@ -175,60 +282,74 @@ return (void __user *)((sp - frame_size) & -8ul); } -static inline int map_signal(int sig) -{ - if (current_thread_info()->exec_domain - && current_thread_info()->exec_domain->signal_invmap - && sig < 32) - return current_thread_info()->exec_domain->signal_invmap[sig]; - else - return sig; -} - static int setup_frame(int sig, struct k_sigaction *ka, sigset_t *set, struct pt_regs * regs) { - sigframe __user *frame; - - frame = get_sigframe(ka, regs, sizeof(sigframe)); + struct sigframe __user *frame; + struct sigcontext sc; + unsigned long restorer; + size_t frame_size; + /* + * gprs_high are only present for a 31-bit task running on + * a 64-bit kernel (see compat_signal.c) but the space for + * gprs_high need to be allocated if vector registers are + * included in the signal frame on a 31-bit system. + */ + frame_size = sizeof(*frame) - sizeof(frame->sregs_ext); + if (MACHINE_HAS_VX) + frame_size += sizeof(frame->sregs_ext); + frame = get_sigframe(ka, regs, frame_size); if (frame == (void __user *) -1UL) - goto give_sigsegv; + return -EFAULT; - if (__copy_to_user(&frame->sc.oldmask, &set->sig, _SIGMASK_COPY_SIZE)) - goto give_sigsegv; + /* Set up backchain. */ + if (__put_user(regs->gprs[15], (addr_t __user *) frame)) + return -EFAULT; + + /* Create struct sigcontext on the signal stack */ + memcpy(&sc.oldmask, &set->sig, _SIGMASK_COPY_SIZE); + sc.sregs = (_sigregs __user __force *) &frame->sregs; + if (__copy_to_user(&frame->sc, &sc, sizeof(frame->sc))) + return -EFAULT; + /* Store registers needed to create the signal frame */ + store_sigregs(); + + /* Create _sigregs on the signal stack */ if (save_sigregs(regs, &frame->sregs)) - goto give_sigsegv; - if (__put_user(&frame->sregs, &frame->sc.sregs)) - goto give_sigsegv; + return -EFAULT; + + /* Place signal number on stack to allow backtrace from handler. */ + if (__put_user(regs->gprs[2], (int __user *) &frame->signo)) + return -EFAULT; + + /* Create _sigregs_ext on the signal stack */ + if (save_sigregs_ext(regs, &frame->sregs_ext)) + return -EFAULT; /* Set up to return from userspace. If provided, use a stub already in userspace. */ if (ka->sa.sa_flags & SA_RESTORER) { - regs->gprs[14] = (unsigned long) - ka->sa.sa_restorer | PSW_ADDR_AMODE; + restorer = (unsigned long) ka->sa.sa_restorer | PSW_ADDR_AMODE; } else { - regs->gprs[14] = (unsigned long) - frame->retcode | PSW_ADDR_AMODE; - if (__put_user(S390_SYSCALL_OPCODE | __NR_sigreturn, - (u16 __user *)(frame->retcode))) - goto give_sigsegv; + /* Signal frame without vector registers are short ! */ + __u16 __user *svc = (void __user *) frame + frame_size - 2; + if (__put_user(S390_SYSCALL_OPCODE | __NR_sigreturn, svc)) + return -EFAULT; + restorer = (unsigned long) svc | PSW_ADDR_AMODE; } - /* Set up backchain. */ - if (__put_user(regs->gprs[15], (addr_t __user *) frame)) - goto give_sigsegv; - /* Set up registers for signal handler */ + regs->gprs[14] = restorer; regs->gprs[15] = (unsigned long) frame; /* Force default amode and default user address space control. */ regs->psw.mask = PSW_MASK_EA | PSW_MASK_BA | - (psw_user_bits & PSW_MASK_ASC) | + (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); + regs->gprs[2] = sig; regs->gprs[3] = (unsigned long) &frame->sc; /* We forgot to include these in the sigcontext. @@ -240,91 +361,92 @@ regs->gprs[5] = regs->int_parm_long; regs->gprs[6] = task_thread_info(current)->last_break; } - - /* Place signal number on stack to allow backtrace from handler. */ - if (__put_user(regs->gprs[2], (int __user *) &frame->signo)) - goto give_sigsegv; return 0; - -give_sigsegv: - force_sigsegv(sig, current); - return -EFAULT; } -static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, - sigset_t *set, struct pt_regs * regs) +static int setup_rt_frame(struct ksignal *ksig, sigset_t *set, + struct pt_regs *regs) { - int err = 0; - rt_sigframe __user *frame; - - frame = get_sigframe(ka, regs, sizeof(rt_sigframe)); + struct rt_sigframe __user *frame; + unsigned long uc_flags, restorer; + size_t frame_size; + frame_size = sizeof(struct rt_sigframe) - sizeof(_sigregs_ext); + /* + * gprs_high are only present for a 31-bit task running on + * a 64-bit kernel (see compat_signal.c) but the space for + * gprs_high need to be allocated if vector registers are + * included in the signal frame on a 31-bit system. + */ + uc_flags = 0; + if (MACHINE_HAS_VX) { + frame_size += sizeof(_sigregs_ext); + uc_flags |= UC_VXRS; + } + frame = get_sigframe(&ksig->ka, regs, frame_size); if (frame == (void __user *) -1UL) - goto give_sigsegv; - - if (copy_siginfo_to_user(&frame->info, info)) - goto give_sigsegv; + return -EFAULT; - /* Create the ucontext. */ - err |= __put_user(0, &frame->uc.uc_flags); - err |= __put_user(NULL, &frame->uc.uc_link); - err |= __save_altstack(&frame->uc.uc_stack, regs->gprs[15]); - err |= save_sigregs(regs, &frame->uc.uc_mcontext); - err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); - if (err) - goto give_sigsegv; + /* Set up backchain. */ + if (__put_user(regs->gprs[15], (addr_t __user *) frame)) + return -EFAULT; /* Set up to return from userspace. If provided, use a stub already in userspace. */ - if (ka->sa.sa_flags & SA_RESTORER) { - regs->gprs[14] = (unsigned long) - ka->sa.sa_restorer | PSW_ADDR_AMODE; + if (ksig->ka.sa.sa_flags & SA_RESTORER) { + restorer = (unsigned long) + ksig->ka.sa.sa_restorer | PSW_ADDR_AMODE; } else { - regs->gprs[14] = (unsigned long) - frame->retcode | PSW_ADDR_AMODE; - if (__put_user(S390_SYSCALL_OPCODE | __NR_rt_sigreturn, - (u16 __user *)(frame->retcode))) - goto give_sigsegv; + __u16 __user *svc = &frame->svc_insn; + if (__put_user(S390_SYSCALL_OPCODE | __NR_rt_sigreturn, svc)) + return -EFAULT; + restorer = (unsigned long) svc | PSW_ADDR_AMODE; } - /* Set up backchain. */ - if (__put_user(regs->gprs[15], (addr_t __user *) frame)) - goto give_sigsegv; + /* Create siginfo on the signal stack */ + if (copy_siginfo_to_user(&frame->info, &ksig->info)) + return -EFAULT; + + /* Store registers needed to create the signal frame */ + store_sigregs(); + + /* Create ucontext on the signal stack. */ + if (__put_user(uc_flags, &frame->uc.uc_flags) || + __put_user(NULL, &frame->uc.uc_link) || + __save_altstack(&frame->uc.uc_stack, regs->gprs[15]) || + save_sigregs(regs, &frame->uc.uc_mcontext) || + __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)) || + save_sigregs_ext(regs, &frame->uc.uc_mcontext_ext)) + return -EFAULT; /* Set up registers for signal handler */ + regs->gprs[14] = restorer; regs->gprs[15] = (unsigned long) frame; /* Force default amode and default user address space control. */ regs->psw.mask = PSW_MASK_EA | PSW_MASK_BA | - (psw_user_bits & PSW_MASK_ASC) | + (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->psw.addr = (unsigned long) ksig->ka.sa.sa_handler | PSW_ADDR_AMODE; - regs->gprs[2] = map_signal(sig); + regs->gprs[2] = ksig->sig; regs->gprs[3] = (unsigned long) &frame->info; regs->gprs[4] = (unsigned long) &frame->uc; regs->gprs[5] = task_thread_info(current)->last_break; return 0; - -give_sigsegv: - force_sigsegv(sig, current); - return -EFAULT; } -static void handle_signal(unsigned long sig, struct k_sigaction *ka, - siginfo_t *info, sigset_t *oldset, - struct pt_regs *regs) +static void handle_signal(struct ksignal *ksig, sigset_t *oldset, + struct pt_regs *regs) { int ret; /* Set up the stack frame */ - if (ka->sa.sa_flags & SA_SIGINFO) - ret = setup_rt_frame(sig, ka, info, oldset, regs); + if (ksig->ka.sa.sa_flags & SA_SIGINFO) + ret = setup_rt_frame(ksig, oldset, regs); else - ret = setup_frame(sig, ka, oldset, regs); - if (ret) - return; - signal_delivered(sig, info, ka, regs, - test_thread_flag(TIF_SINGLE_STEP)); + ret = setup_frame(ksig->sig, &ksig->ka, oldset, regs); + + signal_setup_done(ret, ksig, test_thread_flag(TIF_SINGLE_STEP)); } /* @@ -338,9 +460,7 @@ */ void do_signal(struct pt_regs *regs) { - siginfo_t info; - int signr; - struct k_sigaction ka; + struct ksignal ksig; sigset_t *oldset = sigmask_to_save(); /* @@ -349,10 +469,9 @@ * call information. */ current_thread_info()->system_call = - test_thread_flag(TIF_SYSCALL) ? regs->int_code : 0; - signr = get_signal_to_deliver(&info, &ka, regs, NULL); + test_pt_regs_flag(regs, PIF_SYSCALL) ? regs->int_code : 0; - if (signr > 0) { + if (get_signal(&ksig)) { /* Whee! Actually deliver the signal. */ if (current_thread_info()->system_call) { regs->int_code = current_thread_info()->system_call; @@ -363,7 +482,7 @@ regs->gprs[2] = -EINTR; break; case -ERESTARTSYS: - if (!(ka.sa.sa_flags & SA_RESTART)) { + if (!(ksig.ka.sa.sa_flags & SA_RESTART)) { regs->gprs[2] = -EINTR; break; } @@ -377,17 +496,17 @@ } } /* No longer in a system call */ - clear_thread_flag(TIF_SYSCALL); + clear_pt_regs_flag(regs, PIF_SYSCALL); if (is_compat_task()) - handle_signal32(signr, &ka, &info, oldset, regs); + handle_signal32(&ksig, oldset, regs); else - handle_signal(signr, &ka, &info, oldset, regs); + handle_signal(&ksig, oldset, regs); return; } /* No handlers present - check for system call restart */ - clear_thread_flag(TIF_SYSCALL); + clear_pt_regs_flag(regs, PIF_SYSCALL); if (current_thread_info()->system_call) { regs->int_code = current_thread_info()->system_call; switch (regs->gprs[2]) { @@ -400,9 +519,9 @@ case -ERESTARTNOINTR: /* Restart system call with magic TIF bit. */ regs->gprs[2] = regs->orig_gpr2; - set_thread_flag(TIF_SYSCALL); + set_pt_regs_flag(regs, PIF_SYSCALL); if (test_thread_flag(TIF_SINGLE_STEP)) - set_thread_flag(TIF_PER_TRAP); + clear_pt_regs_flag(regs, PIF_PER_TRAP); break; } }