sys-utils/lscpu: Unblock SIGSEGV before vmware_bdoor

diff --git a/sys-utils/lscpu-virt.c b/sys-utils/lscpu-virt.c
index 4d301271a339afc971b360c15a759a18f5f8aa9d..6ba7c02dc6b80308d758411a332cfee80765f74d 100644 (file)
--- a/sys-utils/lscpu-virt.c
+++ b/sys-utils/lscpu-virt.c
@@ -17,6 +17,7 @@
 #include <unistd.h>
 #include <string.h>
 #include <stdio.h>
+#include <signal.h>
 
 #include "lscpu.h"
 
@@ -454,6 +455,7 @@ void vmware_bdoor(uint32_t *eax, uint32_t *ebx, uint32_t *ecx, uint32_t *edx)
 }
 
 static jmp_buf segv_handler_env;
+static sigset_t oset;
 
 static void
 segv_handler(__attribute__((__unused__)) int sig,
@@ -467,6 +469,7 @@ static int is_vmware_platform(void)
 {
        uint32_t eax, ebx, ecx, edx;
        struct sigaction act, oact;
+       sigset_t set;
 
        /*
         * FIXME: Not reliable for non-root users. Note it works as expected if
@@ -485,8 +488,16 @@ static int is_vmware_platform(void)
         * the signal. All this magic is needed because lscpu
         * isn't supposed to require root privileges.
         */
-       if (sigsetjmp(segv_handler_env, 1))
+       if (sigsetjmp(segv_handler_env, 1)) {
+               if (sigprocmask(SIG_SETMASK, &oset, NULL))
+                       err(EXIT_FAILURE, _("cannot restore signal mask"));
                return 0;
+       }
+
+       sigemptyset(&set);
+       sigaddset(&set, SIGSEGV);
+       if (sigprocmask(SIG_UNBLOCK, &set, &oset))
+               err(EXIT_FAILURE, _("cannot unblock signal"));
 
        memset(&act, 0, sizeof(act));
        act.sa_sigaction = segv_handler;
@@ -500,6 +511,9 @@ static int is_vmware_platform(void)
        if (sigaction(SIGSEGV, &oact, NULL))
                err(EXIT_FAILURE, _("cannot restore signal handler"));
 
+       if (sigprocmask(SIG_SETMASK, &oset, NULL))
+               err(EXIT_FAILURE, _("cannot restore signal mask"));
+
        return eax != (uint32_t)-1 && ebx == VMWARE_BDOOR_MAGIC;
 }