From: Denys Vlasenko <dvlasenk@redhat.com>
Date: Wed, 26 Jun 2013 12:27:11 +0000 (+0200)
Subject: Set strace_child only in the right branch
X-Git-Tag: v4.9~224
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=e8681c926c02dad48aca66f3aba1e33122002c36;p=strace

Set strace_child only in the right branch

"strace_child = pid" assignment was racing in NOMMU case
because of vfork (no way to know which process would win).

After this change, strace_child is set to nonzero only
in one process after [v]fork.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
---

diff --git a/strace.c b/strace.c
index 1415aab3..4fb1b46e 100644
--- a/strace.c
+++ b/strace.c
@@ -1204,7 +1204,7 @@ startup_child(char **argv)
 		prctl(PR_SET_PTRACER, PR_SET_PTRACER_ANY);
 #endif
 
-	strace_child = pid = fork();
+	pid = fork();
 	if (pid < 0) {
 		perror_msg_and_die("fork");
 	}
@@ -1221,6 +1221,7 @@ startup_child(char **argv)
 	/* We are the tracer */
 
 	if (!daemonized_tracer) {
+		strace_child = pid;
 		if (!use_seize) {
 			/* child did PTRACE_TRACEME, nothing to do in parent */
 		} else {