diff options
Diffstat (limited to 'arch/sparc/kernel/signal.c')
-rw-r--r-- | arch/sparc/kernel/signal.c | 84 |
1 files changed, 45 insertions, 39 deletions
diff --git a/arch/sparc/kernel/signal.c b/arch/sparc/kernel/signal.c index 3c312290c3c..3fd1df9f9ba 100644 --- a/arch/sparc/kernel/signal.c +++ b/arch/sparc/kernel/signal.c @@ -145,6 +145,9 @@ asmlinkage void do_sigreturn(struct pt_regs *regs) regs->psr = (up_psr & ~(PSR_ICC | PSR_EF)) | (regs->psr & (PSR_ICC | PSR_EF)); + /* Prevent syscall restart. */ + pt_regs_clear_syscall(regs); + err |= __get_user(fpu_save, &sf->fpu_save); if (fpu_save) @@ -199,6 +202,9 @@ asmlinkage void do_rt_sigreturn(struct pt_regs *regs) regs->psr = (regs->psr & ~PSR_ICC) | (psr & PSR_ICC); + /* Prevent syscall restart. */ + pt_regs_clear_syscall(regs); + err |= __get_user(fpu_save, &sf->fpu_save); if (fpu_save) @@ -245,15 +251,29 @@ static inline int invalid_frame_pointer(void __user *fp, int fplen) static inline void __user *get_sigframe(struct sigaction *sa, struct pt_regs *regs, unsigned long framesize) { - unsigned long sp; + unsigned long sp = regs->u_regs[UREG_FP]; - sp = regs->u_regs[UREG_FP]; + /* + * If we are on the alternate signal stack and would overflow it, don't. + * Return an always-bogus address instead so we will die with SIGSEGV. + */ + if (on_sig_stack(sp) && !likely(on_sig_stack(sp - framesize))) + return (void __user *) -1L; /* This is the X/Open sanctioned signal stack switching. */ if (sa->sa_flags & SA_ONSTACK) { - if (!on_sig_stack(sp) && !((current->sas_ss_sp + current->sas_ss_size) & 7)) + if (sas_ss_flags(sp) == 0) sp = current->sas_ss_sp + current->sas_ss_size; } + + /* Always align the stack frame. This handles two cases. First, + * sigaltstack need not be mindful of platform specific stack + * alignment. Second, if we took this signal because the stack + * is not aligned properly, we'd like to take the signal cleanly + * and report that. + */ + sp &= ~7UL; + return (void __user *)(sp - framesize); } @@ -493,26 +513,36 @@ static inline void syscall_restart(unsigned long orig_i0, struct pt_regs *regs, * want to handle. Thus you cannot kill init even with a SIGKILL even by * mistake. */ -asmlinkage void do_signal(struct pt_regs * regs, unsigned long orig_i0, int restart_syscall) +asmlinkage void do_signal(struct pt_regs * regs, unsigned long orig_i0) { - siginfo_t info; - struct sparc_deliver_cookie cookie; struct k_sigaction ka; - int signr; + int restart_syscall; sigset_t *oldset; + siginfo_t info; + int signr; - cookie.restart_syscall = restart_syscall; - cookie.orig_i0 = orig_i0; + if (pt_regs_is_syscall(regs) && (regs->psr & PSR_C)) + restart_syscall = 1; + else + restart_syscall = 0; if (test_thread_flag(TIF_RESTORE_SIGMASK)) oldset = ¤t->saved_sigmask; else oldset = ¤t->blocked; - signr = get_signal_to_deliver(&info, &ka, regs, &cookie); + signr = get_signal_to_deliver(&info, &ka, regs, NULL); + + /* If the debugger messes with the program counter, it clears + * the software "in syscall" bit, directing us to not perform + * a syscall restart. + */ + if (restart_syscall && !pt_regs_is_syscall(regs)) + restart_syscall = 0; + if (signr > 0) { - if (cookie.restart_syscall) - syscall_restart(cookie.orig_i0, regs, &ka.sa); + if (restart_syscall) + syscall_restart(orig_i0, regs, &ka.sa); handle_signal(signr, &ka, &info, oldset, regs); /* a signal was successfully delivered; the saved @@ -524,16 +554,16 @@ asmlinkage void do_signal(struct pt_regs * regs, unsigned long orig_i0, int rest clear_thread_flag(TIF_RESTORE_SIGMASK); return; } - if (cookie.restart_syscall && + if (restart_syscall && (regs->u_regs[UREG_I0] == ERESTARTNOHAND || regs->u_regs[UREG_I0] == ERESTARTSYS || regs->u_regs[UREG_I0] == ERESTARTNOINTR)) { /* replay the system call when we are done */ - regs->u_regs[UREG_I0] = cookie.orig_i0; + regs->u_regs[UREG_I0] = orig_i0; regs->pc -= 4; regs->npc -= 4; } - if (cookie.restart_syscall && + if (restart_syscall && regs->u_regs[UREG_I0] == ERESTART_RESTARTBLOCK) { regs->u_regs[UREG_G1] = __NR_restart_syscall; regs->pc -= 4; @@ -585,27 +615,3 @@ do_sys_sigstack(struct sigstack __user *ssptr, struct sigstack __user *ossptr, out: return ret; } - -void ptrace_signal_deliver(struct pt_regs *regs, void *cookie) -{ - struct sparc_deliver_cookie *cp = cookie; - - if (cp->restart_syscall && - (regs->u_regs[UREG_I0] == ERESTARTNOHAND || - regs->u_regs[UREG_I0] == ERESTARTSYS || - regs->u_regs[UREG_I0] == ERESTARTNOINTR)) { - /* replay the system call when we are done */ - regs->u_regs[UREG_I0] = cp->orig_i0; - regs->pc -= 4; - regs->npc -= 4; - cp->restart_syscall = 0; - } - - if (cp->restart_syscall && - regs->u_regs[UREG_I0] == ERESTART_RESTARTBLOCK) { - regs->u_regs[UREG_G1] = __NR_restart_syscall; - regs->pc -= 4; - regs->npc -= 4; - cp->restart_syscall = 0; - } -} |