trace: Use properly sized type for PTRACE_GETEVENTMSG
authorMichal Sojka <michal.sojka@cvut.cz>
Mon, 30 Jul 2018 07:31:09 +0000 (09:31 +0200)
committerJohn Crispin <john@phrozen.org>
Mon, 30 Jul 2018 13:24:15 +0000 (15:24 +0200)
Without this, on 64-bit systems, ptrace call corrupts memory because
it stores 64bit value to 32bit pid_t variable.

Signed-off-by: Michal Sojka <michal.sojka@cvut.cz>
trace/trace.c

index 27cf108..665c22e 100644 (file)
@@ -211,7 +211,9 @@ static void tracer_cb(struct uloop_process *c, int ret)
                           (ret >> 8) == (SIGTRAP | (PTRACE_EVENT_CLONE << 8))) {
                        struct tracee *child = calloc(1, sizeof(struct tracee));
 
-                       ptrace(PTRACE_GETEVENTMSG, c->pid, 0, &child->proc.pid);
+                       unsigned long msg;
+                       ptrace(PTRACE_GETEVENTMSG, c->pid, 0, &msg);
+                       child->proc.pid = msg;
                        child->proc.cb = tracer_cb;
                        ptrace(ptrace_restart, child->proc.pid, 0, 0);
                        uloop_process_add(&child->proc);