diff options
Diffstat (limited to 'arch/sparc64/kernel/signal32.c')
| -rw-r--r-- | arch/sparc64/kernel/signal32.c | 24 |
1 files changed, 23 insertions, 1 deletions
diff --git a/arch/sparc64/kernel/signal32.c b/arch/sparc64/kernel/signal32.c index 91f8d0826db1..0f6b7b156efd 100644 --- a/arch/sparc64/kernel/signal32.c +++ b/arch/sparc64/kernel/signal32.c @@ -268,6 +268,9 @@ void do_sigreturn32(struct pt_regs *regs) regs->tstate &= ~(TSTATE_ICC|TSTATE_XCC); regs->tstate |= psr_to_tstate_icc(psr); + /* Prevent syscall restart. */ + pt_regs_clear_trap_type(regs); + err |= __get_user(fpu_save, &sf->fpu_save); if (fpu_save) err |= restore_fpu_state32(regs, &sf->fpu_state); @@ -351,6 +354,9 @@ asmlinkage void do_rt_sigreturn32(struct pt_regs *regs) regs->tstate &= ~(TSTATE_ICC|TSTATE_XCC); regs->tstate |= psr_to_tstate_icc(psr); + /* Prevent syscall restart. */ + pt_regs_clear_trap_type(regs); + err |= __get_user(fpu_save, &sf->fpu_save); if (fpu_save) err |= restore_fpu_state32(regs, &sf->fpu_state); @@ -400,11 +406,27 @@ static void __user *get_sigframe(struct sigaction *sa, struct pt_regs *regs, uns regs->u_regs[UREG_FP] &= 0x00000000ffffffffUL; 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); } |