diff --git a/CMakeLists.txt b/CMakeLists.txt
index d749c25..2718125 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -87,7 +87,7 @@ ADD_DEPENDENCIES(preload-seccomp syscall-names-h)
 endif()
 
 IF(JAIL_SUPPORT)
-ADD_EXECUTABLE(ujail jail/jail.c jail/elf.c jail/capabilities.c)
+ADD_EXECUTABLE(ujail jail/jail.c jail/elf.c jail/fs.c jail/capabilities.c)
 TARGET_LINK_LIBRARIES(ujail ubox blobmsg_json)
 INSTALL(TARGETS ujail
 	RUNTIME DESTINATION ${CMAKE_INSTALL_SBINDIR}
diff --git a/jail/elf.c b/jail/elf.c
index a26aa0b..c8d1221 100644
--- a/jail/elf.c
+++ b/jail/elf.c
@@ -12,26 +12,25 @@
  */
 
 #define _GNU_SOURCE
-#include <sys/mman.h>
 
-#include <stdlib.h>
-#include <unistd.h>
-#include <stdio.h>
 #include <string.h>
 #include <sys/stat.h>
 #include <fcntl.h>
-#include <libgen.h>
 #include <glob.h>
 #include <elf.h>
+#include <assert.h>
+#include <linux/limits.h>
 
 #include <libubox/utils.h>
 
+#include "fs.h"
 #include "elf.h"
+#include "log.h"
 
 struct avl_tree libraries;
 static LIST_HEAD(library_paths);
 
-void alloc_library_path(const char *path)
+static void alloc_library_path(const char *path)
 {
 	struct stat s;
 	if (stat(path, &s))
@@ -51,7 +50,11 @@ void alloc_library_path(const char *path)
 	DEBUG("adding ld.so path %s\n", path);
 }
 
-static void alloc_library(const char *path, const char *name)
+/*
+ * path = full path
+ * name = soname/avl key
+ */
+void alloc_library(const char *path, const char *name)
 {
 	struct library *l;
 	char *_name, *_path;
@@ -66,52 +69,39 @@ static void alloc_library(const char *path, const char *name)
 	l->path = strcpy(_path, path);
 
 	avl_insert(&libraries, &l->avl);
-	DEBUG("adding library %s/%s\n", path, name);
+	DEBUG("adding library %s (%s)\n", path, name);
 }
 
-static int elf_open(char **dir, const char *file)
+int elf_open(char **fullpath, const char *file)
 {
+	*fullpath = NULL;
+	assert(file[0] != '/');
+
 	struct library_path *p;
-	char path[256];
+	char path[PATH_MAX];
 	int fd = -1;
 
-	*dir = NULL;
-
 	list_for_each_entry(p, &library_paths, list) {
-		if (strlen(p->path))
-			snprintf(path, sizeof(path), "%s/%s", p->path, file);
-		else
-			strncpy(path, file, sizeof(path));
+		snprintf(path, sizeof(path), "%s/%s", p->path, file);
 		fd = open(path, O_RDONLY);
 		if (fd >= 0) {
-			*dir = p->path;
+			*fullpath = strdup(path);
 			break;
 		}
 	}
 
-	if (fd == -1)
-		fd = open(file, O_RDONLY);
-
 	return fd;
 }
 
 char* find_lib(const char *file)
 {
 	struct library *l;
-	static char path[256];
-	const char *p;
 
 	l = avl_find_element(&libraries, file, l, avl);
 	if (!l)
 		return NULL;
 
-	p = l->path;
-	if (strstr(p, "local"))
-		p = "/lib";
-
-	snprintf(path, sizeof(path), "%s/%s", p, file);
-
-	return path;
+	return l->path;
 }
 
 static int elf64_find_section(const char *map, unsigned int type, unsigned int *offset, unsigned int *size, unsigned int *vaddr)
@@ -201,7 +191,7 @@ static int elf32_scan_dynamic(const char *map, int dyn_offset, int dyn_size, int
 		if (curr->d_tag != DT_NEEDED)
 			continue;
 
-		if (elf_load_deps(&strtab[curr->d_un.d_val]))
+		if (add_path_and_deps(&strtab[curr->d_un.d_val], 1, -1, 1) == -1)
 			return -1;
 	}
 
@@ -235,85 +225,48 @@ static int elf64_scan_dynamic(const char *map, int dyn_offset, int dyn_size, int
 		if (curr->d_tag != DT_NEEDED)
 			continue;
 
-		if (elf_load_deps(&strtab[curr->d_un.d_val]))
+		if (add_path_and_deps(&strtab[curr->d_un.d_val], 1, -1, 1) == -1)
 			return -1;
 	}
 
 	return 0;
 }
 
-int elf_load_deps(const char *library)
+int elf_load_deps(const char *path, const char *map)
 {
 	unsigned int dyn_offset, dyn_size;
 	unsigned int load_offset, load_vaddr;
-	struct stat s;
-	char *map = NULL, *dir = NULL;
-	int clazz, fd, ret = -1;
-
-	if (avl_find(&libraries, library))
-		return 0;
-
-	fd = elf_open(&dir, library);
-
-	if (fd < 0) {
-		ERROR("failed to open %s\n", library);
-		return -1;
-	}
-
-	if (fstat(fd, &s) == -1) {
-		ERROR("failed to stat %s\n", library);
-		ret = -1;
-		goto err_out;
-	}
-
-	map = mmap(NULL, s.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
-	if (map == MAP_FAILED) {
-		ERROR("failed to mmap %s\n", library);
-		ret = -1;
-		goto err_out;
-	}
+	unsigned int interp_offset;
 
 	if (elf_find_section(map, PT_LOAD, &load_offset, NULL, &load_vaddr)) {
-		ERROR("failed to load the .load section from %s\n", library);
-		ret = -1;
-		goto err_out;
+		ERROR("failed to load the .load section from %s\n", path);
+		return -1;
 	}
 
 	if (elf_find_section(map, PT_DYNAMIC, &dyn_offset, &dyn_size, NULL)) {
-		ERROR("failed to load the .dynamic section from %s\n", library);
-		ret = -1;
-		goto err_out;
+		ERROR("failed to load the .dynamic section from %s\n", path);
+		return -1;
 	}
 
-	if (dir) {
-		alloc_library(dir, library);
-	} else {
-		char *elf1 = strdup(library);
-		char *elf2 = strdup(library);
-
-		alloc_library(dirname(elf1), basename(elf2));
-		free(elf1);
-		free(elf2);
+	if (elf_find_section(map, PT_INTERP, &interp_offset, NULL, NULL) == 0) {
+		add_path_and_deps(map+interp_offset, 1, -1, 0);
 	}
-	clazz = map[EI_CLASS];
+
+	int clazz = map[EI_CLASS];
 
 	if (clazz == ELFCLASS32)
-		ret = elf32_scan_dynamic(map, dyn_offset, dyn_size, load_vaddr - load_offset);
+		return elf32_scan_dynamic(map, dyn_offset, dyn_size, load_vaddr - load_offset);
 	else if (clazz == ELFCLASS64)
-		ret = elf64_scan_dynamic(map, dyn_offset, dyn_size, load_vaddr - load_offset);
-
-err_out:
-	if (map)
-		munmap(map, s.st_size);
-	close(fd);
+		return elf64_scan_dynamic(map, dyn_offset, dyn_size, load_vaddr - load_offset);
 
-	return ret;
+	ERROR("unknown elf format %d\n", clazz);
+	return -1;
 }
 
-void load_ldso_conf(const char *conf)
+static void load_ldso_conf(const char *conf)
 {
 	FILE* fp = fopen(conf, "r");
-	char line[256];
+	char line[PATH_MAX];
 
 	if (!fp) {
 		DEBUG("failed to open %s\n", conf);
@@ -323,7 +276,7 @@ void load_ldso_conf(const char *conf)
 	while (!feof(fp)) {
 		int len;
 
-		if (!fgets(line, 256, fp))
+		if (!fgets(line, sizeof(line), fp))
 			break;
 		len = strlen(line);
 		if (len < 2)
@@ -355,3 +308,12 @@ void load_ldso_conf(const char *conf)
 
 	fclose(fp);
 }
+
+void init_library_path(void)
+{
+	avl_init(&libraries, avl_strcmp, false, NULL);
+	alloc_library_path("/lib");
+	alloc_library_path("/lib64");
+	alloc_library_path("/usr/lib");
+	load_ldso_conf("/etc/ld.so.conf");
+}
diff --git a/jail/elf.h b/jail/elf.h
index 6c14c39..ea67837 100644
--- a/jail/elf.h
+++ b/jail/elf.h
@@ -15,8 +15,6 @@
 #include <libubox/avl.h>
 #include <libubox/avl-cmp.h>
 
-#include "log.h"
-
 struct library {
 	struct avl_node avl;
 	char *name;
@@ -30,9 +28,10 @@ struct library_path {
 
 struct avl_tree libraries;
 
-void alloc_library_path(const char *path);
-int elf_load_deps(const char *library);
+void alloc_library(const char *path, const char *name);
+int elf_open(char **fullpath, const char *file);
+int elf_load_deps(const char *path, const char *map);
 char* find_lib(const char *file);
-void load_ldso_conf(const char *conf);
+void init_library_path(void);
 
 #endif
diff --git a/jail/fs.c b/jail/fs.c
new file mode 100644
index 0000000..c1ae1da
--- /dev/null
+++ b/jail/fs.c
@@ -0,0 +1,179 @@
+/*
+ * Copyright (C) 2015 John Crispin <blogic@openwrt.org>
+ * Copyright (C) 2015 Etienne Champetier <champetier.etienne@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1
+ * as published by the Free Software Foundation
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#define _GNU_SOURCE
+
+#include <assert.h>
+#include <elf.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <linux/limits.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <sys/mman.h>
+#include <unistd.h>
+
+#include <libubox/avl.h>
+#include <libubox/avl-cmp.h>
+
+#include "elf.h"
+#include "fs.h"
+#include "jail.h"
+#include "log.h"
+
+struct mount {
+        struct avl_node avl;
+        const char *path;
+        int readonly;
+        int error;
+};
+
+struct avl_tree mounts;
+
+static int add_mount(const char *path, int readonly, int error)
+{
+	if (avl_find(&mounts, path))
+		return 1;
+
+	struct mount *m;
+	m = calloc(1, sizeof(struct mount));
+	assert(m != NULL);
+	m->avl.key = m->path = strdup(path);
+	m->readonly = readonly;
+	m->error = error;
+
+	avl_insert(&mounts, &m->avl);
+	DEBUG("adding mount %s ro(%d) err(%d)\n", m->path, m->readonly, m->error != 0);
+	return 0;
+}
+
+int mount_all(const char *jailroot) {
+	struct library *l;
+	struct mount *m;
+
+	avl_for_each_element(&libraries, l, avl)
+		add_mount(l->path, 1, -1);
+
+	avl_for_each_element(&mounts, m, avl)
+		if (mount_bind(jailroot, m->path, m->readonly, m->error))
+			return -1;
+
+	return 0;
+}
+
+void mount_list_init(void) {
+	avl_init(&mounts, avl_strcmp, false, NULL);
+}
+
+static int add_script_interp(const char *path, const char *map, int size)
+{
+	int start = 2;
+	while (start < size && map[start] != '/') {
+		start++;
+	}
+	if (start >= size) {
+		ERROR("bad script interp (%s)", path);
+		return -1;
+	}
+	int stop = start + 1;
+	while (stop < size && map[stop] > 0x20 && map[stop] <= 0x7e) {
+		stop++;
+	}
+	if (stop >= size || (stop-start) > PATH_MAX) {
+		ERROR("bad script interp (%s)", path);
+		return -1;
+	}
+	char buf[PATH_MAX];
+	strncpy(buf, map+start, stop-start);
+	return add_path_and_deps(buf, 1, -1, 0);
+}
+
+int add_path_and_deps(const char *path, int readonly, int error, int lib)
+{
+	assert(path != NULL);
+
+	if (lib == 0 && path[0] != '/') {
+		ERROR("%s is not an absolute path\n", path);
+		return error;
+	}
+
+	char *map = NULL;
+	int fd, ret = -1;
+	if (path[0] == '/') {
+		if (avl_find(&mounts, path))
+			return 0;
+		fd = open(path, O_RDONLY);
+		if (fd == -1)
+			return error;
+		add_mount(path, readonly, error);
+	} else {
+		if (avl_find(&libraries, path))
+			return 0;
+		char *fullpath;
+		fd = elf_open(&fullpath, path);
+		if (fd == -1)
+			return error;
+		if (fullpath) {
+			alloc_library(fullpath, path);
+			free(fullpath);
+		}
+	}
+
+	struct stat s;
+	if (fstat(fd, &s) == -1) {
+		ERROR("fstat(%s) failed: %s\n", path, strerror(errno));
+		ret = error;
+		goto out;
+	}
+
+	if (!S_ISREG(s.st_mode)) {
+		ret = 0;
+		goto out;
+	}
+
+	/* too small to be an ELF or a script */
+	if (s.st_size < 4) {
+		ret = 0;
+		goto out;
+	}
+
+	map = mmap(NULL, s.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
+	if (map == MAP_FAILED) {
+		ERROR("failed to mmap %s\n", path);
+		ret = -1;
+		goto out;
+	}
+
+	if (map[0] == '#' && map[1] == '!') {
+		ret = add_script_interp(path, map, s.st_size);
+		goto out;
+	}
+
+	if (map[0] == ELFMAG0 && map[1] == ELFMAG1 && map[2] == ELFMAG2 && map[3] == ELFMAG3) {
+		ret = elf_load_deps(path, map);
+		goto out;
+	}
+
+	ret = 0;
+
+out:
+	if (fd >= 0)
+		close(fd);
+	if (map)
+		munmap(map, s.st_size);
+
+	return ret;
+}
+
diff --git a/jail/fs.h b/jail/fs.h
new file mode 100644
index 0000000..0839d5c
--- /dev/null
+++ b/jail/fs.h
@@ -0,0 +1,20 @@
+/*
+ * Copyright (C) 2015 Etienne Champetier <champetier.etienne@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1
+ * as published by the Free Software Foundation
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef _FS_H__
+
+int add_path_and_deps(const char *path, int readonly, int error, int lib);
+int mount_all(const char *jailroot);
+void mount_list_init(void);
+
+#endif
diff --git a/jail/jail.c b/jail/jail.c
index 08babde..db74504 100644
--- a/jail/jail.c
+++ b/jail/jail.c
@@ -18,19 +18,20 @@
 
 #include <stdlib.h>
 #include <unistd.h>
-#include <values.h>
 #include <errno.h>
-#include <stdio.h>
 #include <string.h>
 #include <sys/stat.h>
 #include <fcntl.h>
 #include <libgen.h>
 #include <sched.h>
+#include <linux/limits.h>
 
-#include "elf.h"
 #include "capabilities.h"
+#include "elf.h"
+#include "fs.h"
+#include "jail.h"
+#include "log.h"
 
-#include <libubox/list.h>
 #include <libubox/uloop.h>
 
 #define STACK_SIZE	(1024 * 1024)
@@ -48,16 +49,6 @@ static struct {
 	int sysfs;
 } opts;
 
-struct extra {
-	struct list_head list;
-
-	const char *path;
-	const char *name;
-	int readonly;
-};
-
-static LIST_HEAD(extras);
-
 extern int pivot_root(const char *new_root, const char *put_old);
 
 int debug = 0;
@@ -89,32 +80,23 @@ static int mkdir_p(char *dir, mode_t mask)
 	return ret;
 }
 
-static int mount_bind(const char *root, const char *path, const char *name, int readonly, int error)
+int mount_bind(const char *root, const char *path, int readonly, int error)
 {
-	const char *p = path;
 	struct stat s;
-	char old[256];
-	char new[256];
+	char new[PATH_MAX];
 	int fd;
 
-	if (strstr(p, "local"))
-		p = "/lib";
-
-	snprintf(old, sizeof(old), "%s/%s", path, name);
-	snprintf(new, sizeof(new), "%s%s", root, p);
-
-	mkdir_p(new, 0755);
-
-	snprintf(new, sizeof(new), "%s%s/%s", root, p, name);
-
-	if (stat(old, &s)) {
-		ERROR("%s does not exist\n", old);
+	if (stat(path, &s)) {
+		ERROR("%s does not exist\n", path);
 		return error;
 	}
 
+	snprintf(new, sizeof(new), "%s%s", root, path);
 	if (S_ISDIR(s.st_mode)) {
 		mkdir_p(new, 0755);
 	} else {
+		mkdir_p(dirname(new), 0755);
+		snprintf(new, sizeof(new), "%s%s", root, path);
 		fd = creat(new, 0644);
 		if (fd == -1) {
 			ERROR("failed to create %s: %s\n", new, strerror(errno));
@@ -123,8 +105,8 @@ static int mount_bind(const char *root, const char *path, const char *name, int
 		close(fd);
 	}
 
-	if (mount(old, new, NULL, MS_BIND, NULL)) {
-		ERROR("failed to mount -B %s %s: %s\n", old, new, strerror(errno));
+	if (mount(path, new, NULL, MS_BIND, NULL)) {
+		ERROR("failed to mount -B %s %s: %s\n", path, new, strerror(errno));
 		return -1;
 	}
 
@@ -133,16 +115,13 @@ static int mount_bind(const char *root, const char *path, const char *name, int
 		return -1;
 	}
 
-	DEBUG("mount -B %s %s\n", old, new);
+	DEBUG("mount -B %s %s\n", path, new);
 
 	return 0;
 }
 
-static int build_jail_fs()
+static int build_jail_fs(void)
 {
-	struct library *l;
-	struct extra *m;
-
 	if (mount("tmpfs", opts.path, "tmpfs", MS_NOATIME, "mode=0755")) {
 		ERROR("tmpfs mount failed %s\n", strerror(errno));
 		return -1;
@@ -153,29 +132,20 @@ static int build_jail_fs()
 		return -1;
 	}
 
-	avl_init(&libraries, avl_strcmp, false, NULL);
-	alloc_library_path("/lib64");
-	alloc_library_path("/lib");
-	alloc_library_path("/usr/lib");
-	load_ldso_conf("/etc/ld.so.conf");
-
-	if (elf_load_deps(*opts.jail_argv)) {
+	if (add_path_and_deps(*opts.jail_argv, 1, -1, 0)) {
 		ERROR("failed to load dependencies\n");
 		return -1;
 	}
 
-	if (opts.seccomp && elf_load_deps("libpreload-seccomp.so")) {
+	if (opts.seccomp && add_path_and_deps("libpreload-seccomp.so", 1, -1, 1)) {
 		ERROR("failed to load libpreload-seccomp.so\n");
 		return -1;
 	}
 
-	avl_for_each_element(&libraries, l, avl)
-		if (mount_bind(opts.path, l->path, l->name, 1, -1))
-			return -1;
-
-	list_for_each_entry(m, &extras, list)
-		if (mount_bind(opts.path, m->path, m->name, m->readonly, 0))
-			return -1;
+	if (mount_all(opts.path)) {
+		ERROR("mount_all() failed\n");
+		return -1;
+	}
 
 	char *mpoint;
 	if (asprintf(&mpoint, "%s/old", opts.path) < 0) {
@@ -209,8 +179,8 @@ static int build_jail_fs()
 static char** build_envp(const char *seccomp)
 {
 	static char *envp[MAX_ENVP];
-	static char preload_var[64];
-	static char seccomp_var[64];
+	static char preload_var[PATH_MAX];
+	static char seccomp_var[PATH_MAX];
 	static char debug_var[] = "LD_DEBUG=all";
 	char *preload_lib = find_lib("libpreload-seccomp.so");
 	int count = 0;
@@ -256,7 +226,7 @@ ujail will not use namespace/build a jail,\n\
 and will only drop capabilities/apply seccomp filter.\n\n");
 }
 
-static int exec_jail()
+static int exec_jail(void)
 {
 	char **envp = build_envp(opts.seccomp);
 	if (!envp)
@@ -306,24 +276,6 @@ static struct uloop_process jail_process = {
 	.cb = jail_process_handler,
 };
 
-static void add_extra(char *name, int readonly)
-{
-	struct extra *f;
-
-	if (*name != '/') {
-		ERROR("%s is not an absolute path\n", name);
-		return;
-	}
-
-	f = calloc(1, sizeof(struct extra));
-
-	f->name = basename(name);
-	f->path = dirname(strdup(name));
-	f->readonly = readonly;
-
-	list_add_tail(&f->list, &extras);
-}
-
 int main(int argc, char **argv)
 {
 	uid_t uid = getuid();
@@ -338,6 +290,8 @@ int main(int argc, char **argv)
 	}
 
 	umask(022);
+	mount_list_init();
+	init_library_path();
 
 	while ((ch = getopt(argc, argv, OPT_ARGS)) != -1) {
 		switch (ch) {
@@ -358,11 +312,11 @@ int main(int argc, char **argv)
 			break;
 		case 'S':
 			opts.seccomp = optarg;
-			add_extra(optarg, 1);
+			add_path_and_deps(optarg, 1, -1, 0);
 			break;
 		case 'C':
 			opts.capabilities = optarg;
-			add_extra(optarg, 1);
+			add_path_and_deps(optarg, 1, -1, 0);
 			break;
 		case 'P':
 			opts.namespace = 1;
@@ -373,19 +327,19 @@ int main(int argc, char **argv)
 			break;
 		case 'r':
 			opts.namespace = 1;
-			add_extra(optarg, 1);
+			add_path_and_deps(optarg, 1, 0, 0);
 			break;
 		case 'w':
 			opts.namespace = 1;
-			add_extra(optarg, 0);
+			add_path_and_deps(optarg, 0, 0, 0);
 			break;
 		case 'u':
 			opts.namespace = 1;
-			add_extra(ubus, 0);
+			add_path_and_deps(ubus, 0, -1, 0);
 			break;
 		case 'l':
 			opts.namespace = 1;
-			add_extra(log, 0);
+			add_path_and_deps(log, 0, -1, 0);
 			break;
 		}
 	}
diff --git a/jail/jail.h b/jail/jail.h
new file mode 100644
index 0000000..fc69ef6
--- /dev/null
+++ b/jail/jail.h
@@ -0,0 +1,18 @@
+/*
+ * Copyright (C) 2015 Etienne Champetier <champetier.etienne@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1
+ * as published by the Free Software Foundation
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef _JAIL_H__
+
+int mount_bind(const char *root, const char *path, int readonly, int error);
+
+#endif
diff --git a/jail/log.h b/jail/log.h
index b1d201e..e56fc6a 100644
--- a/jail/log.h
+++ b/jail/log.h
@@ -12,6 +12,7 @@
  */
 
 extern int debug;
+#include <stdio.h>
 #include <syslog.h>
 
 #define INFO(fmt, ...) do { \
