diff options
Diffstat (limited to 'arch/mips/kernel/signal.c')
| -rw-r--r-- | arch/mips/kernel/signal.c | 46 |
1 files changed, 43 insertions, 3 deletions
diff --git a/arch/mips/kernel/signal.c b/arch/mips/kernel/signal.c index f091786187a..bf094fc4c7e 100644 --- a/arch/mips/kernel/signal.c +++ b/arch/mips/kernel/signal.c @@ -124,6 +124,37 @@ int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc) return err; } +int fpcsr_pending(unsigned int __user *fpcsr) +{ + int err, sig = 0; + unsigned int csr, enabled; + + err = __get_user(csr, fpcsr); + enabled = FPU_CSR_UNI_X | ((csr & FPU_CSR_ALL_E) << 5); + /* + * If the signal handler set some FPU exceptions, clear it and + * send SIGFPE. + */ + if (csr & enabled) { + csr &= ~enabled; + err |= __put_user(csr, fpcsr); + sig = SIGFPE; + } + return err ?: sig; +} + +static int +check_and_restore_fp_context(struct sigcontext __user *sc) +{ + int err, sig; + + err = sig = fpcsr_pending(&sc->sc_fpc_csr); + if (err > 0) + err = 0; + err |= restore_fp_context(sc); + return err ?: sig; +} + int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc) { unsigned int used_math; @@ -162,7 +193,8 @@ int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc) if (used_math()) { /* restore fpu context if we have used it before */ own_fpu(); - err |= restore_fp_context(sc); + if (!err) + err = check_and_restore_fp_context(sc); } else { /* signal handler may have used FPU. Give it up. */ lose_fpu(); @@ -332,6 +364,7 @@ asmlinkage void sys_sigreturn(nabi_no_regargs struct pt_regs regs) { struct sigframe __user *frame; sigset_t blocked; + int sig; frame = (struct sigframe __user *) regs.regs[29]; if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) @@ -345,8 +378,11 @@ asmlinkage void sys_sigreturn(nabi_no_regargs struct pt_regs regs) recalc_sigpending(); spin_unlock_irq(¤t->sighand->siglock); - if (restore_sigcontext(®s, &frame->sf_sc)) + sig = restore_sigcontext(®s, &frame->sf_sc); + if (sig < 0) goto badframe; + else if (sig) + force_sig(sig, current); /* * Don't let your children do this ... @@ -368,6 +404,7 @@ asmlinkage void sys_rt_sigreturn(nabi_no_regargs struct pt_regs regs) struct rt_sigframe __user *frame; sigset_t set; stack_t st; + int sig; frame = (struct rt_sigframe __user *) regs.regs[29]; if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) @@ -381,8 +418,11 @@ asmlinkage void sys_rt_sigreturn(nabi_no_regargs struct pt_regs regs) recalc_sigpending(); spin_unlock_irq(¤t->sighand->siglock); - if (restore_sigcontext(®s, &frame->rs_uc.uc_mcontext)) + sig = restore_sigcontext(®s, &frame->rs_uc.uc_mcontext); + if (sig < 0) goto badframe; + else if (sig) + force_sig(sig, current); if (__copy_from_user(&st, &frame->rs_uc.uc_stack, sizeof(st))) goto badframe; |