diff options
Diffstat (limited to 'arch/x86/kernel/signal.c')
| -rw-r--r-- | arch/x86/kernel/signal.c | 52 |
1 files changed, 26 insertions, 26 deletions
diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c index 5ddc7ec20e75..f9804080ccb3 100644 --- a/arch/x86/kernel/signal.c +++ b/arch/x86/kernel/signal.c @@ -61,8 +61,7 @@ regs->seg = GET_SEG(seg) | 3; \ } while (0) -int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, - unsigned long *pax) +int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc) { void __user *buf; unsigned int tmpflags; @@ -81,7 +80,7 @@ int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, #endif /* CONFIG_X86_32 */ COPY(di); COPY(si); COPY(bp); COPY(sp); COPY(bx); - COPY(dx); COPY(cx); COPY(ip); + COPY(dx); COPY(cx); COPY(ip); COPY(ax); #ifdef CONFIG_X86_64 COPY(r8); @@ -94,27 +93,20 @@ int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, COPY(r15); #endif /* CONFIG_X86_64 */ -#ifdef CONFIG_X86_32 COPY_SEG_CPL3(cs); COPY_SEG_CPL3(ss); -#else /* !CONFIG_X86_32 */ - /* Kernel saves and restores only the CS segment register on signals, - * which is the bare minimum needed to allow mixed 32/64-bit code. - * App's signal handler can save/restore other segments if needed. */ - COPY_SEG_CPL3(cs); -#endif /* CONFIG_X86_32 */ get_user_ex(tmpflags, &sc->flags); regs->flags = (regs->flags & ~FIX_EFLAGS) | (tmpflags & FIX_EFLAGS); regs->orig_ax = -1; /* disable syscall checks */ get_user_ex(buf, &sc->fpstate); - - get_user_ex(*pax, &sc->ax); } get_user_catch(err); err |= restore_xstate_sig(buf, config_enabled(CONFIG_X86_32)); + force_iret(); + return err; } @@ -162,8 +154,9 @@ int setup_sigcontext(struct sigcontext __user *sc, void __user *fpstate, #else /* !CONFIG_X86_32 */ put_user_ex(regs->flags, &sc->flags); put_user_ex(regs->cs, &sc->cs); - put_user_ex(0, &sc->gs); - put_user_ex(0, &sc->fs); + put_user_ex(0, &sc->__pad2); + put_user_ex(0, &sc->__pad1); + put_user_ex(regs->ss, &sc->ss); #endif /* CONFIG_X86_32 */ put_user_ex(fpstate, &sc->fpstate); @@ -457,9 +450,19 @@ static int __setup_rt_frame(int sig, struct ksignal *ksig, regs->sp = (unsigned long)frame; - /* Set up the CS register to run signal handlers in 64-bit mode, - even if the handler happens to be interrupting 32-bit code. */ + /* + * Set up the CS and SS registers to run signal handlers in + * 64-bit mode, even if the handler happens to be interrupting + * 32-bit or 16-bit code. + * + * SS is subtle. In 64-bit mode, we don't need any particular + * SS descriptor, but we do need SS to be valid. It's possible + * that the old SS is entirely bogus -- this can happen if the + * signal we're trying to deliver is #GP or #SS caused by a bad + * SS value. + */ regs->cs = __USER_CS; + regs->ss = __USER_DS; return 0; } @@ -539,7 +542,6 @@ asmlinkage unsigned long sys_sigreturn(void) { struct pt_regs *regs = current_pt_regs(); struct sigframe __user *frame; - unsigned long ax; sigset_t set; frame = (struct sigframe __user *)(regs->sp - 8); @@ -553,9 +555,9 @@ asmlinkage unsigned long sys_sigreturn(void) set_current_blocked(&set); - if (restore_sigcontext(regs, &frame->sc, &ax)) + if (restore_sigcontext(regs, &frame->sc)) goto badframe; - return ax; + return regs->ax; badframe: signal_fault(regs, frame, "sigreturn"); @@ -568,7 +570,6 @@ asmlinkage long sys_rt_sigreturn(void) { struct pt_regs *regs = current_pt_regs(); struct rt_sigframe __user *frame; - unsigned long ax; sigset_t set; frame = (struct rt_sigframe __user *)(regs->sp - sizeof(long)); @@ -579,13 +580,13 @@ asmlinkage long sys_rt_sigreturn(void) set_current_blocked(&set); - if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &ax)) + if (restore_sigcontext(regs, &frame->uc.uc_mcontext)) goto badframe; if (restore_altstack(&frame->uc.uc_stack)) goto badframe; - return ax; + return regs->ax; badframe: signal_fault(regs, frame, "rt_sigreturn"); @@ -665,7 +666,7 @@ handle_signal(struct ksignal *ksig, struct pt_regs *regs) * Ensure the signal handler starts with the new fpu state. */ if (used_math()) - drop_init_fpu(current); + fpu_reset_state(current); } signal_setup_done(failed, ksig, test_thread_flag(TIF_SINGLESTEP)); } @@ -766,7 +767,6 @@ asmlinkage long sys32_x32_rt_sigreturn(void) struct pt_regs *regs = current_pt_regs(); struct rt_sigframe_x32 __user *frame; sigset_t set; - unsigned long ax; frame = (struct rt_sigframe_x32 __user *)(regs->sp - 8); @@ -777,13 +777,13 @@ asmlinkage long sys32_x32_rt_sigreturn(void) set_current_blocked(&set); - if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &ax)) + if (restore_sigcontext(regs, &frame->uc.uc_mcontext)) goto badframe; if (compat_restore_altstack(&frame->uc.uc_stack)) goto badframe; - return ax; + return regs->ax; badframe: signal_fault(regs, frame, "x32 rt_sigreturn"); |