libselinux: use reentrant strtok_r(3)

Use the reentrant version strtok_r(3) instead of strtok(3) to avoid potential data races with concurrent threads. Signed-off-by: Christian Göttsche <[email protected]> Acked-by: James Carter <[email protected]>
SELinuxProject · Jan 25, 2024 · 82195e7 · 82195e7
1 parent 3e3661f
commit 82195e7
Showing 1 changed file with 7 additions and 5 deletions.
diff --git a/libselinux/src/selinux_restorecon.c b/libselinux/src/selinux_restorecon.c
@@ -243,7 +243,7 @@ static uint64_t exclude_non_seclabel_mounts(void)
  int index = 0, found = 0;
  uint64_t nfile = 0;
  char *mount_info[4];
- char *buf = NULL, *item;
+ char *buf = NULL, *item, *saveptr;
 
  /* Check to see if the kernel supports seclabel */
  if (uname(&uts) == 0 && strverscmp(uts.release, "2.6.30") < 0)
@@ -258,13 +258,14 @@ static uint64_t exclude_non_seclabel_mounts(void)
  while (getline(&buf, &len, fp) != -1) {
  found = 0;
  index = 0;
- item = strtok(buf, " ");
+ saveptr = NULL;
+ item = strtok_r(buf, " ", &saveptr);
  while (item != NULL) {
  mount_info[index] = item;
  index++;
  if (index == 4)
  break;
- item = strtok(NULL, " ");
+ item = strtok_r(NULL, " ", &saveptr);
  }
  if (index < 4) {
  selinux_log(SELINUX_ERROR,
@@ -276,14 +277,15 @@ static uint64_t exclude_non_seclabel_mounts(void)
  /* Remove pre-existing entry */
  remove_exclude(mount_info[1]);
 
- item = strtok(mount_info[3], ",");
+ saveptr = NULL;
+ item = strtok_r(mount_info[3], ",", &saveptr);
  while (item != NULL) {
  if (strcmp(item, "seclabel") == 0) {
  found = 1;
  nfile += file_system_count(mount_info[1]);
  break;
  }
- item = strtok(NULL, ",");
+ item = strtok_r(NULL, ",", &saveptr);
  }
 
  /* Exclude mount points without the seclabel option */