X-Git-Url: https://git.lttng.org/?a=blobdiff_plain;f=src%2Fcommon%2Frunas.c;h=4742a792eca105f35f1a8e2d194db9aeecd55a66;hb=2d85a600590b23ca5ca1e182187d08f44808ef80;hp=88ed773152cc7c959b81084fb58a93ee9c3409ae;hpb=edb025e87637ff74565647ad7756ecac46899d2a;p=lttng-tools.git

diff --git a/src/common/runas.c b/src/common/runas.c
index 88ed77315..4742a792e 100644
--- a/src/common/runas.c
+++ b/src/common/runas.c
@@ -38,12 +38,11 @@
 
 #define RUNAS_CHILD_STACK_SIZE	10485760
 
-#ifndef __FreeBSD__
-# ifndef MAP_STACK
-#  define MAP_STACK		0
-# endif
-#else	/* FreeBSD MAP_STACK always return -ENOMEM */
-# define MAP_STACK		0
+#ifdef __FreeBSD__
+/* FreeBSD MAP_STACK always return -ENOMEM */
+#define LTTNG_MAP_STACK		0
+#else
+#define LTTNG_MAP_STACK		MAP_STACK
 #endif
 
 #ifndef MAP_GROWSDOWN
@@ -201,7 +200,7 @@ int child_run_as(void *_data)
 }
 
 static
-int run_as(int (*cmd)(void *data), void *data, uid_t uid, gid_t gid)
+int run_as_clone(int (*cmd)(void *data), void *data, uid_t uid, gid_t gid)
 {
 	struct run_as_data run_as_data;
 	int ret = 0;
@@ -239,7 +238,7 @@ int run_as(int (*cmd)(void *data), void *data, uid_t uid, gid_t gid)
 	run_as_data.retval_pipe = retval_pipe[1];	/* write end */
 	child_stack = mmap(NULL, RUNAS_CHILD_STACK_SIZE,
 		PROT_WRITE | PROT_READ,
-		MAP_PRIVATE | MAP_GROWSDOWN | MAP_ANONYMOUS | MAP_STACK,
+		MAP_PRIVATE | MAP_GROWSDOWN | MAP_ANONYMOUS | LTTNG_MAP_STACK,
 		-1, 0);
 	if (child_stack == MAP_FAILED) {
 		perror("mmap");
@@ -293,6 +292,29 @@ end:
 	return retval.i;
 }
 
+/*
+ * To be used on setups where gdb has issues debugging programs using
+ * clone/rfork. Note that this is for debuging ONLY, and should not be
+ * considered secure.
+ */
+static
+int run_as_noclone(int (*cmd)(void *data), void *data, uid_t uid, gid_t gid)
+{
+	return cmd(data);
+}
+
+static
+int run_as(int (*cmd)(void *data), void *data, uid_t uid, gid_t gid)
+{
+	if (!getenv("LTTNG_DEBUG_NOCLONE")) {
+		DBG("Using run_as_clone");
+		return run_as_clone(cmd, data, uid, gid);
+	} else {
+		DBG("Using run_as_noclone");
+		return run_as_noclone(cmd, data, uid, gid);
+	}
+}
+
 int run_as_mkdir_recursive(const char *path, mode_t mode, uid_t uid, gid_t gid)
 {
 	struct run_as_mkdir_data data;