diff --git a/sys/amd64/linux/linux_ptrace.c b/sys/amd64/linux/linux_ptrace.c
index 32d736d4909..67d8b121fbf 100644
--- a/sys/amd64/linux/linux_ptrace.c
+++ b/sys/amd64/linux/linux_ptrace.c
@@ -379,6 +379,7 @@ linux_ptrace_getsiginfo(struct thread *td, pid_t pid, l_ulong data)
 	}
 
 	sig = bsd_to_linux_signal(lwpinfo.pl_siginfo.si_signo);
+	memset(&l_siginfo, 0, sizeof(l_siginfo));
 	siginfo_to_lsiginfo(&lwpinfo.pl_siginfo, &l_siginfo, sig);
 	error = copyout(&l_siginfo, (void *)data, sizeof(l_siginfo));
 	return (error);