From: Andrew Bartlett <abartlet@samba.org>
Date: Sat, 23 May 2020 09:24:07 +0000 (+1200)
Subject: lib/util: Allow gdb to be started by samba_start_debugger() under the default Ubuntu... 
X-Git-Tag: ldb-2.2.0~321
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=d279cf7bede639314cb2b9ba52d44218dc2fc353;p=thirdparty%2Fsamba.git

lib/util: Allow gdb to be started by samba_start_debugger() under the default Ubuntu restrictions

Ubuntu (in particular) restricts ptrace by default for security reasons
but the processe to be traced can allow tracing by a child process
using prctl().  This matches what is done for panic action =

Signed-off-by: Andrew Bartlett <abartlet@samba.org>
Reviewed-by: Gary Lockyer <gary@catalyst.net.nz>
---

diff --git a/lib/util/util.c b/lib/util/util.c
index 0d9ffe5cb7b..a90d48f6f1b 100644
--- a/lib/util/util.c
+++ b/lib/util/util.c
@@ -36,6 +36,10 @@
 #include "samba_util.h"
 #include "lib/util/select.h"
 
+#ifdef HAVE_SYS_PRCTL_H
+#include <sys/prctl.h>
+#endif
+
 #undef malloc
 #undef strcasecmp
 #undef strncasecmp
@@ -1282,6 +1286,12 @@ void anonymous_shared_free(void *ptr)
 void samba_start_debugger(void)
 {
 	char *cmd = NULL;
+#if defined(HAVE_PRCTL) && defined(PR_SET_PTRACER)
+	/*
+	 * Make sure all children can attach a debugger.
+	 */
+	prctl(PR_SET_PTRACER, getpid(), 0, 0, 0);
+#endif
 	if (asprintf(&cmd, "xterm -e \"gdb --pid %u\"&", getpid()) == -1) {
 		return;
 	}