Improve signal handling

2 files changed, 21 insertions, 3 deletions

diff --git a/cpulist.c b/cpulist.c
index c8cc7a5..4496764 100644
--- a/cpulist.c
+++ b/cpulist.c
@@ -24,6 +24,7 @@
 #include <dirent.h>
 #include <sys/types.h>
 #include <stdlib.h>
+#include <signal.h>
 #include "debug.h"
 #include "sysfs.h"
 #include "cputemp2maxfreq.h"
@@ -68,6 +69,7 @@ int cpulist_find_cpus()
  struct dirent *cpu_dirent;
  char sysfs_file[309];
  int package;
+ sigset_t newset, oldset;
 
  DEBUG1_CPULIST("Started\n")
 
@@ -78,6 +80,13 @@ int cpulist_find_cpus()
  } 
  cpudata.cpulist_len=0;
 
+// Block signals to prevent malloc/free race conditions
+ sigemptyset(&newset);
+ sigaddset(&newset,SIGTERM);
+ sigaddset(&newset,SIGINT);
+ sigaddset(&newset,SIGQUIT);
+ sigprocmask(SIG_BLOCK,&newset,&oldset);
+
 // Open the CPU directory in sysfs
  cpudir=opendir("/sys/devices/system/cpu");
  if (cpudir==NULL)
@@ -110,6 +119,9 @@ int cpulist_find_cpus()
  }
  closedir(cpudir);
 
+// Restore signal mask
+ sigprocmask(SIG_SETMASK,&oldset,NULL);
+
  DEBUG1_CPULIST("Found %d CPU's\n",config.cpulist_len);
  if (cpudata.cpulist_len==0)
  {
diff --git a/cputemp2maxfreq.c b/cputemp2maxfreq.c
index d146158..212fb39 100644
--- a/cputemp2maxfreq.c
+++ b/cputemp2maxfreq.c
@@ -92,6 +92,7 @@ int main(int argc,char **argv)
  struct s_sensor sensor;
  char *transition_latency_remark;
  char sensor_string[20];
+ struct sigaction sigact={0};
 
  argparse(argc,argv);
  config.logger("%s version %s, buildtime %s %s",config.name,version(),__DATE__,__TIME__);
@@ -263,9 +264,14 @@ int main(int argc,char **argv)
  if (config.csvlog[0]!=0) csvlog_init();
 
 // Set signal handlers
- signal(SIGTERM,signal_handler);
- signal(SIGINT,signal_handler);
- signal(SIGQUIT,signal_handler);
+ sigact.sa_handler=&signal_handler;
+ sigemptyset(&sigact.sa_mask);
+ sigaddset(&sigact.sa_mask,SIGTERM);
+ sigaddset(&sigact.sa_mask,SIGINT);
+ sigaddset(&sigact.sa_mask,SIGQUIT);
+ sigaction(SIGTERM,&sigact,NULL);
+ sigaction(SIGINT,&sigact,NULL);
+ sigaction(SIGQUIT,&sigact,NULL);
 
  while(1)
  {