CVE-2007-4559 Patch

levels/01_chroot_image/rd.py

@@ -61,7 +61,26 @@ def create_container_root(image_name, image_dir, container_id, container_dir):
         # Fun fact: tar files may contain *nix devices! *facepalm*
         members = [m for m in t.getmembers()
                    if m.type not in (tarfile.CHRTYPE, tarfile.BLKTYPE)]
-        t.extractall(container_root, members=members)
+        def is_within_directory(directory, target):
+
+            abs_directory = os.path.abspath(directory)
+            abs_target = os.path.abspath(target)
+
+            prefix = os.path.commonprefix([abs_directory, abs_target])
+
+            return prefix == abs_directory
+
+        def safe_extract(tar, path=".", members=None, *, numeric_owner=False):
+
+            for member in tar.getmembers():
+                member_path = os.path.join(path, member.name)
+                if not is_within_directory(path, member_path):
+                    raise Exception("Attempted Path Traversal in Tar File")
+
+            tar.extractall(path, members, numeric_owner=numeric_owner) 
+
+
+        safe_extract(t, container_root, members=members)
 
     return container_root
 

levels/02_mount_ns/rd.py

@@ -42,7 +42,26 @@ def create_container_root(image_name, image_dir, container_id, container_dir):
         # Fun fact: tar files may contain *nix devices! *facepalm*
         members = [m for m in t.getmembers()
                    if m.type not in (tarfile.CHRTYPE, tarfile.BLKTYPE)]
-        t.extractall(container_root, members=members)
+        def is_within_directory(directory, target):
+
+            abs_directory = os.path.abspath(directory)
+            abs_target = os.path.abspath(target)
+
+            prefix = os.path.commonprefix([abs_directory, abs_target])
+
+            return prefix == abs_directory
+
+        def safe_extract(tar, path=".", members=None, *, numeric_owner=False):
+
+            for member in tar.getmembers():
+                member_path = os.path.join(path, member.name)
+                if not is_within_directory(path, member_path):
+                    raise Exception("Attempted Path Traversal in Tar File")
+
+            tar.extractall(path, members, numeric_owner=numeric_owner) 
+
+
+        safe_extract(t, container_root, members=members)
 
     return container_root
 

levels/03_pivot_root/rd.py

@@ -47,7 +47,26 @@ def create_container_root(image_name, image_dir, container_id, container_dir):
         # Fun fact: tar files may contain *nix devices! *facepalm*
         members = [m for m in t.getmembers()
                    if m.type not in (tarfile.CHRTYPE, tarfile.BLKTYPE)]
-        t.extractall(container_root, members=members)
+        def is_within_directory(directory, target):
+
+            abs_directory = os.path.abspath(directory)
+            abs_target = os.path.abspath(target)
+
+            prefix = os.path.commonprefix([abs_directory, abs_target])
+
+            return prefix == abs_directory
+
+        def safe_extract(tar, path=".", members=None, *, numeric_owner=False):
+
+            for member in tar.getmembers():
+                member_path = os.path.join(path, member.name)
+                if not is_within_directory(path, member_path):
+                    raise Exception("Attempted Path Traversal in Tar File")
+
+            tar.extractall(path, members, numeric_owner=numeric_owner) 
+
+
+        safe_extract(t, container_root, members=members)
 
     return container_root
 

levels/04_overlay/rd.py

@@ -45,7 +45,26 @@ def create_container_root(image_name, image_dir, container_id, container_dir):
             # Fun fact: tar files may contain *nix devices! *facepalm*
             members = [m for m in t.getmembers()
                        if m.type not in (tarfile.CHRTYPE, tarfile.BLKTYPE)]
-            t.extractall(container_root, members=members)
+            def is_within_directory(directory, target):
+
+                abs_directory = os.path.abspath(directory)
+                abs_target = os.path.abspath(target)
+
+                prefix = os.path.commonprefix([abs_directory, abs_target])
+
+                return prefix == abs_directory
+
+            def safe_extract(tar, path=".", members=None, *, numeric_owner=False):
+
+                for member in tar.getmembers():
+                    member_path = os.path.join(path, member.name)
+                    if not is_within_directory(path, member_path):
+                        raise Exception("Attempted Path Traversal in Tar File")
+
+                tar.extractall(path, members, numeric_owner=numeric_owner) 
+
+
+            safe_extract(t, container_root, members=members)
 
     # TODO: create directories for copy-on-write (uppperdir), overlay workdir,
     #       and a mount point

levels/05_uts_namespace/rd.py

@@ -36,7 +36,26 @@ def create_container_root(image_name, image_dir, container_id, container_dir):
             # Fun fact: tar files may contain *nix devices! *facepalm*
             members = [m for m in t.getmembers()
                        if m.type not in (tarfile.CHRTYPE, tarfile.BLKTYPE)]
-            t.extractall(image_root, members=members)
+            def is_within_directory(directory, target):
+
+                abs_directory = os.path.abspath(directory)
+                abs_target = os.path.abspath(target)
+
+                prefix = os.path.commonprefix([abs_directory, abs_target])
+
+                return prefix == abs_directory
+
+            def safe_extract(tar, path=".", members=None, *, numeric_owner=False):
+
+                for member in tar.getmembers():
+                    member_path = os.path.join(path, member.name)
+                    if not is_within_directory(path, member_path):
+                        raise Exception("Attempted Path Traversal in Tar File")
+
+                tar.extractall(path, members, numeric_owner=numeric_owner) 
+
+
+            safe_extract(t, image_root, members=members)
 
     # Create directories for copy-on-write (uppperdir), overlay workdir,
     # and a mount point

levels/06_pid_namespace/rd.py

@@ -36,7 +36,26 @@ def create_container_root(image_name, image_dir, container_id, container_dir):
             # Fun fact: tar files may contain *nix devices! *facepalm*
             members = [m for m in t.getmembers()
                        if m.type not in (tarfile.CHRTYPE, tarfile.BLKTYPE)]
-            t.extractall(image_root, members=members)
+            def is_within_directory(directory, target):
+
+                abs_directory = os.path.abspath(directory)
+                abs_target = os.path.abspath(target)
+
+                prefix = os.path.commonprefix([abs_directory, abs_target])
+
+                return prefix == abs_directory
+
+            def safe_extract(tar, path=".", members=None, *, numeric_owner=False):
+
+                for member in tar.getmembers():
+                    member_path = os.path.join(path, member.name)
+                    if not is_within_directory(path, member_path):
+                        raise Exception("Attempted Path Traversal in Tar File")
+
+                tar.extractall(path, members, numeric_owner=numeric_owner) 
+
+
+            safe_extract(t, image_root, members=members)
 
     # Create directories for copy-on-write (uppperdir), overlay workdir,
     # and a mount point

levels/07_net_namespace/rd.py

@@ -35,7 +35,26 @@ def create_container_root(image_name, image_dir, container_id, container_dir):
             # Fun fact: tar files may contain *nix devices! *facepalm*
             members = [m for m in t.getmembers()
                        if m.type not in (tarfile.CHRTYPE, tarfile.BLKTYPE)]
-            t.extractall(image_root, members=members)
+            def is_within_directory(directory, target):
+
+                abs_directory = os.path.abspath(directory)
+                abs_target = os.path.abspath(target)
+
+                prefix = os.path.commonprefix([abs_directory, abs_target])
+
+                return prefix == abs_directory
+
+            def safe_extract(tar, path=".", members=None, *, numeric_owner=False):
+
+                for member in tar.getmembers():
+                    member_path = os.path.join(path, member.name)
+                    if not is_within_directory(path, member_path):
+                        raise Exception("Attempted Path Traversal in Tar File")
+
+                tar.extractall(path, members, numeric_owner=numeric_owner) 
+
+
+            safe_extract(t, image_root, members=members)
 
     # Create directories for copy-on-write (uppperdir), overlay workdir,
     # and a mount point

levels/08_cpu_cgroup/rd.py

@@ -35,7 +35,26 @@ def create_container_root(image_name, image_dir, container_id, container_dir):
             # Fun fact: tar files may contain *nix devices! *facepalm*
             members = [m for m in t.getmembers()
                        if m.type not in (tarfile.CHRTYPE, tarfile.BLKTYPE)]
-            t.extractall(image_root, members=members)
+            def is_within_directory(directory, target):
+
+                abs_directory = os.path.abspath(directory)
+                abs_target = os.path.abspath(target)
+
+                prefix = os.path.commonprefix([abs_directory, abs_target])
+
+                return prefix == abs_directory
+
+            def safe_extract(tar, path=".", members=None, *, numeric_owner=False):
+
+                for member in tar.getmembers():
+                    member_path = os.path.join(path, member.name)
+                    if not is_within_directory(path, member_path):
+                        raise Exception("Attempted Path Traversal in Tar File")
+
+                tar.extractall(path, members, numeric_owner=numeric_owner) 
+
+
+            safe_extract(t, image_root, members=members)
 
     # Create directories for copy-on-write (uppperdir), overlay workdir,
     # and a mount point

levels/09_memory_cgorup/rd.py

@@ -35,7 +35,26 @@ def create_container_root(image_name, image_dir, container_id, container_dir):
             # Fun fact: tar files may contain *nix devices! *facepalm*
             members = [m for m in t.getmembers()
                        if m.type not in (tarfile.CHRTYPE, tarfile.BLKTYPE)]
-            t.extractall(image_root, members=members)
+            def is_within_directory(directory, target):
+
+                abs_directory = os.path.abspath(directory)
+                abs_target = os.path.abspath(target)
+
+                prefix = os.path.commonprefix([abs_directory, abs_target])
+
+                return prefix == abs_directory
+
+            def safe_extract(tar, path=".", members=None, *, numeric_owner=False):
+
+                for member in tar.getmembers():
+                    member_path = os.path.join(path, member.name)
+                    if not is_within_directory(path, member_path):
+                        raise Exception("Attempted Path Traversal in Tar File")
+
+                tar.extractall(path, members, numeric_owner=numeric_owner) 
+
+
+            safe_extract(t, image_root, members=members)
 
     # Create directories for copy-on-write (uppperdir), overlay workdir,
     # and a mount point

levels/10_setuid/rd.py

@@ -36,7 +36,26 @@ def create_container_root(image_name, image_dir, container_id, container_dir):
             # Fun fact: tar files may contain *nix devices! *facepalm*
             members = [m for m in t.getmembers()
                        if m.type not in (tarfile.CHRTYPE, tarfile.BLKTYPE)]
-            t.extractall(image_root, members=members)
+            def is_within_directory(directory, target):
+
+                abs_directory = os.path.abspath(directory)
+                abs_target = os.path.abspath(target)
+
+                prefix = os.path.commonprefix([abs_directory, abs_target])
+
+                return prefix == abs_directory
+
+            def safe_extract(tar, path=".", members=None, *, numeric_owner=False):
+
+                for member in tar.getmembers():
+                    member_path = os.path.join(path, member.name)
+                    if not is_within_directory(path, member_path):
+                        raise Exception("Attempted Path Traversal in Tar File")
+
+                tar.extractall(path, members, numeric_owner=numeric_owner) 
+
+
+            safe_extract(t, image_root, members=members)
 
     # Create directories for copy-on-write (uppperdir), overlay workdir,
     # and a mount point