libsandbox: add more exec wrappers

While the execvp() is a common entry point, the other ones are often used
as well.  While they don't take environ pointers directly, the env could
have been modified before calling the exec function, which means we need
to restore our LD_PRELOAD setting.

So now we support execv/execve/fexecve/popen/system.  Missing from this
list are the execl* funcs, but that's because they aren't exactly easy to
interpose with the structure of their variable arguments.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>

1 files changed, 16 insertions, 0 deletions

diff --git a/tests/script-4.sh b/tests/script-4.sh
new file mode 100755
index 0000000..a5f0755
--- /dev/null
+++ b/tests/script-4.sh
@@ -0,0 +1,16 @@
+#!/bin/sh
+# make sure LD_PRELOAD makes it back into env on exec
+
+checkit() {
+	if ! eval "$@" | grep -q '^LD_PRELOAD=.*libsandbox.so.*' ; then
+		echo "LD_PRELOAD was not reset when running:"
+		echo "	$*"
+		exit 1
+	fi
+}
+
+checkit "env -uLD_PRELOAD env"
+checkit "(unset LD_PRELOAD; env)"
+checkit "env LD_PRELOAD= env"
+checkit "env LD_PRELOAD=libc.so env"
+exit 0