diff --git a/Libraries/LibC/spawn.cpp b/Libraries/LibC/spawn.cpp
index 62b778105e..c8815d9274 100644
--- a/Libraries/LibC/spawn.cpp
+++ b/Libraries/LibC/spawn.cpp
@@ -90,7 +90,7 @@ extern "C" {
             }
         }
         if (flags & POSIX_SPAWN_SETSIGMASK) {
-            if (sigprocmask(SIG_SETMASK, &attr->sigmask, nullptr) != 0) {
+            if (sigprocmask(SIG_SETMASK, &attr->sigmask, nullptr) < 0) {
                 perror("posix_spawn sigprocmask");
                 exit(127);
             }