From: Alex Barcelo Date: Fri, 14 Mar 2014 14:36:55 +0000 (+0000) Subject: signal: added a wrapper for sigprocmask function X-Git-Url: http://git.osdn.net/view?a=commitdiff_plain;h=1c275925bfbbc2de84a8f0e09d1dd70bbefb6da3;p=qmiga%2Fqemu.git signal: added a wrapper for sigprocmask function Create a wrapper for signal mask changes initiated by the guest; (this includes syscalls and also the sigreturns from signal.c) this will give us a place to put code which prevents the guest from changing the handling of signals used by QEMU itself internally. The wrapper is called from all the guest-initiated sigprocmask, but is not called from internal qemu sigprocmask calls. Signed-off-by: Alex Barcelo [PMM: Added calls to wrapper for sigprocmask uses in signal.c when setting the signal mask on entry and exit from signal handlers, since these also are guest-provided signal masks.] Signed-off-by: Peter Maydell Signed-off-by: Riku Voipio --- diff --git a/linux-user/qemu.h b/linux-user/qemu.h index c2f74f33d6..4d24e74775 100644 --- a/linux-user/qemu.h +++ b/linux-user/qemu.h @@ -235,6 +235,7 @@ int host_to_target_signal(int sig); long do_sigreturn(CPUArchState *env); long do_rt_sigreturn(CPUArchState *env); abi_long do_sigaltstack(abi_ulong uss_addr, abi_ulong uoss_addr, abi_ulong sp); +int do_sigprocmask(int how, const sigset_t *set, sigset_t *oldset); #ifdef TARGET_I386 /* vm86.c */ diff --git a/linux-user/signal.c b/linux-user/signal.c index 209855efcb..9e6a4952a7 100644 --- a/linux-user/signal.c +++ b/linux-user/signal.c @@ -197,6 +197,16 @@ void target_to_host_old_sigset(sigset_t *sigset, target_to_host_sigset(sigset, &d); } +/* Wrapper for sigprocmask function + * Emulates a sigprocmask in a safe way for the guest. Note that set and oldset + * are host signal set, not guest ones. This wraps the sigprocmask host calls + * that should be protected (calls originated from guest) + */ +int do_sigprocmask(int how, const sigset_t *set, sigset_t *oldset) +{ + return sigprocmask(how, set, oldset); +} + /* siginfo conversion */ static inline void host_to_target_siginfo_noswap(target_siginfo_t *tinfo, @@ -1056,7 +1066,7 @@ long do_sigreturn(CPUX86State *env) } target_to_host_sigset_internal(&set, &target_set); - sigprocmask(SIG_SETMASK, &set, NULL); + do_sigprocmask(SIG_SETMASK, &set, NULL); /* restore registers */ if (restore_sigcontext(env, &frame->sc, &eax)) @@ -1081,7 +1091,7 @@ long do_rt_sigreturn(CPUX86State *env) if (!lock_user_struct(VERIFY_READ, frame, frame_addr, 1)) goto badframe; target_to_host_sigset(&set, &frame->uc.tuc_sigmask); - sigprocmask(SIG_SETMASK, &set, NULL); + do_sigprocmask(SIG_SETMASK, &set, NULL); if (restore_sigcontext(env, &frame->uc.tuc_mcontext, &eax)) goto badframe; @@ -1220,7 +1230,7 @@ static int target_restore_sigframe(CPUARMState *env, uint64_t pstate; target_to_host_sigset(&set, &sf->uc.tuc_sigmask); - sigprocmask(SIG_SETMASK, &set, NULL); + do_sigprocmask(SIG_SETMASK, &set, NULL); for (i = 0; i < 31; i++) { __get_user(env->xregs[i], &sf->uc.tuc_mcontext.regs[i]); @@ -1861,7 +1871,7 @@ static long do_sigreturn_v1(CPUARMState *env) } target_to_host_sigset_internal(&host_set, &set); - sigprocmask(SIG_SETMASK, &host_set, NULL); + do_sigprocmask(SIG_SETMASK, &host_set, NULL); if (restore_sigcontext(env, &frame->sc)) goto badframe; @@ -1942,7 +1952,7 @@ static int do_sigframe_return_v2(CPUARMState *env, target_ulong frame_addr, abi_ulong *regspace; target_to_host_sigset(&host_set, &uc->tuc_sigmask); - sigprocmask(SIG_SETMASK, &host_set, NULL); + do_sigprocmask(SIG_SETMASK, &host_set, NULL); if (restore_sigcontext(env, &uc->tuc_mcontext)) return 1; @@ -2033,7 +2043,7 @@ static long do_rt_sigreturn_v1(CPUARMState *env) goto badframe; target_to_host_sigset(&host_set, &frame->uc.tuc_sigmask); - sigprocmask(SIG_SETMASK, &host_set, NULL); + do_sigprocmask(SIG_SETMASK, &host_set, NULL); if (restore_sigcontext(env, &frame->uc.tuc_mcontext)) goto badframe; @@ -2444,7 +2454,7 @@ long do_sigreturn(CPUSPARCState *env) } target_to_host_sigset_internal(&host_set, &set); - sigprocmask(SIG_SETMASK, &host_set, NULL); + do_sigprocmask(SIG_SETMASK, &host_set, NULL); if (err) goto segv_and_exit; @@ -2567,7 +2577,7 @@ void sparc64_set_context(CPUSPARCState *env) goto do_sigsegv; } target_to_host_sigset_internal(&set, &target_set); - sigprocmask(SIG_SETMASK, &set, NULL); + do_sigprocmask(SIG_SETMASK, &set, NULL); } env->pc = pc; env->npc = npc; @@ -2656,7 +2666,7 @@ void sparc64_get_context(CPUSPARCState *env) err = 0; - sigprocmask(0, NULL, &set); + do_sigprocmask(0, NULL, &set); host_to_target_sigset_internal(&target_set, &set); if (TARGET_NSIG_WORDS == 1) { err |= __put_user(target_set.sig[0], @@ -2991,7 +3001,7 @@ long do_sigreturn(CPUMIPSState *regs) } target_to_host_sigset_internal(&blocked, &target_set); - sigprocmask(SIG_SETMASK, &blocked, NULL); + do_sigprocmask(SIG_SETMASK, &blocked, NULL); if (restore_sigcontext(regs, &frame->sf_sc)) goto badframe; @@ -3095,7 +3105,7 @@ long do_rt_sigreturn(CPUMIPSState *env) goto badframe; target_to_host_sigset(&blocked, &frame->rs_uc.tuc_sigmask); - sigprocmask(SIG_SETMASK, &blocked, NULL); + do_sigprocmask(SIG_SETMASK, &blocked, NULL); if (restore_sigcontext(env, &frame->rs_uc.tuc_mcontext)) goto badframe; @@ -3385,7 +3395,7 @@ long do_sigreturn(CPUSH4State *regs) goto badframe; target_to_host_sigset_internal(&blocked, &target_set); - sigprocmask(SIG_SETMASK, &blocked, NULL); + do_sigprocmask(SIG_SETMASK, &blocked, NULL); if (restore_sigcontext(regs, &frame->sc, &r0)) goto badframe; @@ -3414,7 +3424,7 @@ long do_rt_sigreturn(CPUSH4State *regs) goto badframe; target_to_host_sigset(&blocked, &frame->uc.tuc_sigmask); - sigprocmask(SIG_SETMASK, &blocked, NULL); + do_sigprocmask(SIG_SETMASK, &blocked, NULL); if (restore_sigcontext(regs, &frame->uc.tuc_mcontext, &r0)) goto badframe; @@ -3644,7 +3654,7 @@ long do_sigreturn(CPUMBState *env) goto badframe; } target_to_host_sigset_internal(&set, &target_set); - sigprocmask(SIG_SETMASK, &set, NULL); + do_sigprocmask(SIG_SETMASK, &set, NULL); restore_sigcontext(&frame->uc.tuc_mcontext, env); /* We got here through a sigreturn syscall, our path back is via an @@ -3819,7 +3829,7 @@ long do_sigreturn(CPUCRISState *env) goto badframe; } target_to_host_sigset_internal(&set, &target_set); - sigprocmask(SIG_SETMASK, &set, NULL); + do_sigprocmask(SIG_SETMASK, &set, NULL); restore_sigcontext(&frame->sc, env); unlock_user_struct(frame, frame_addr, 0); @@ -4350,7 +4360,7 @@ long do_sigreturn(CPUS390XState *env) } target_to_host_sigset_internal(&set, &target_set); - sigprocmask(SIG_SETMASK, &set, NULL); /* ~_BLOCKABLE? */ + do_sigprocmask(SIG_SETMASK, &set, NULL); /* ~_BLOCKABLE? */ if (restore_sigregs(env, &frame->sregs)) { goto badframe; @@ -4378,7 +4388,7 @@ long do_rt_sigreturn(CPUS390XState *env) } target_to_host_sigset(&set, &frame->uc.tuc_sigmask); - sigprocmask(SIG_SETMASK, &set, NULL); /* ~_BLOCKABLE? */ + do_sigprocmask(SIG_SETMASK, &set, NULL); /* ~_BLOCKABLE? */ if (restore_sigregs(env, &frame->uc.tuc_mcontext)) { goto badframe; @@ -4906,7 +4916,7 @@ long do_sigreturn(CPUPPCState *env) goto sigsegv; #endif target_to_host_sigset_internal(&blocked, &set); - sigprocmask(SIG_SETMASK, &blocked, NULL); + do_sigprocmask(SIG_SETMASK, &blocked, NULL); if (__get_user(sr_addr, &sc->regs)) goto sigsegv; @@ -4950,7 +4960,7 @@ static int do_setcontext(struct target_ucontext *ucp, CPUPPCState *env, int sig) return 1; target_to_host_sigset_internal(&blocked, &set); - sigprocmask(SIG_SETMASK, &blocked, NULL); + do_sigprocmask(SIG_SETMASK, &blocked, NULL); if (restore_user_regs(env, mcp, sig)) goto sigsegv; @@ -5324,7 +5334,7 @@ long do_sigreturn(CPUM68KState *env) } target_to_host_sigset_internal(&set, &target_set); - sigprocmask(SIG_SETMASK, &set, NULL); + do_sigprocmask(SIG_SETMASK, &set, NULL); /* restore registers */ @@ -5352,7 +5362,7 @@ long do_rt_sigreturn(CPUM68KState *env) goto badframe; target_to_host_sigset_internal(&set, &target_set); - sigprocmask(SIG_SETMASK, &set, NULL); + do_sigprocmask(SIG_SETMASK, &set, NULL); /* restore registers */ @@ -5599,7 +5609,7 @@ long do_sigreturn(CPUAlphaState *env) } target_to_host_sigset_internal(&set, &target_set); - sigprocmask(SIG_SETMASK, &set, NULL); + do_sigprocmask(SIG_SETMASK, &set, NULL); if (restore_sigcontext(env, sc)) { goto badframe; @@ -5622,7 +5632,7 @@ long do_rt_sigreturn(CPUAlphaState *env) goto badframe; } target_to_host_sigset(&set, &frame->uc.tuc_sigmask); - sigprocmask(SIG_SETMASK, &set, NULL); + do_sigprocmask(SIG_SETMASK, &set, NULL); if (restore_sigcontext(env, &frame->uc.tuc_mcontext)) { goto badframe; @@ -5739,7 +5749,7 @@ void process_pending_signals(CPUArchState *cpu_env) sigaddset(&set, target_to_host_signal(sig)); /* block signals in the handler using Linux */ - sigprocmask(SIG_BLOCK, &set, &old_set); + do_sigprocmask(SIG_BLOCK, &set, &old_set); /* save the previous blocked signal state to restore it at the end of the signal execution (see do_sigreturn) */ host_to_target_sigset_internal(&target_old_set, &old_set); diff --git a/linux-user/syscall.c b/linux-user/syscall.c index b8086b883f..e404a32c0f 100644 --- a/linux-user/syscall.c +++ b/linux-user/syscall.c @@ -6029,7 +6029,7 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1, { sigset_t cur_set; abi_ulong target_set; - sigprocmask(0, NULL, &cur_set); + do_sigprocmask(0, NULL, &cur_set); host_to_target_old_sigset(&target_set, &cur_set); ret = target_set; } @@ -6040,10 +6040,10 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1, { sigset_t set, oset, cur_set; abi_ulong target_set = arg1; - sigprocmask(0, NULL, &cur_set); + do_sigprocmask(0, NULL, &cur_set); target_to_host_old_sigset(&set, &target_set); sigorset(&set, &set, &cur_set); - sigprocmask(SIG_SETMASK, &set, &oset); + do_sigprocmask(SIG_SETMASK, &set, &oset); host_to_target_old_sigset(&target_set, &oset); ret = target_set; } @@ -6074,7 +6074,7 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1, mask = arg2; target_to_host_old_sigset(&set, &mask); - ret = get_errno(sigprocmask(how, &set, &oldset)); + ret = get_errno(do_sigprocmask(how, &set, &oldset)); if (!is_error(ret)) { host_to_target_old_sigset(&mask, &oldset); ret = mask; @@ -6108,7 +6108,7 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1, how = 0; set_ptr = NULL; } - ret = get_errno(sigprocmask(how, set_ptr, &oldset)); + ret = get_errno(do_sigprocmask(how, set_ptr, &oldset)); if (!is_error(ret) && arg3) { if (!(p = lock_user(VERIFY_WRITE, arg3, sizeof(target_sigset_t), 0))) goto efault; @@ -6148,7 +6148,7 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1, how = 0; set_ptr = NULL; } - ret = get_errno(sigprocmask(how, set_ptr, &oldset)); + ret = get_errno(do_sigprocmask(how, set_ptr, &oldset)); if (!is_error(ret) && arg3) { if (!(p = lock_user(VERIFY_WRITE, arg3, sizeof(target_sigset_t), 0))) goto efault; @@ -8161,7 +8161,7 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1, } mask = arg2; target_to_host_old_sigset(&set, &mask); - sigprocmask(how, &set, &oldset); + do_sigprocmask(how, &set, &oldset); host_to_target_old_sigset(&mask, &oldset); ret = mask; }