diff --git a/lib/finchfs.c b/lib/finchfs.c
index 02d12df..43ac048 100644
--- a/lib/finchfs.c
+++ b/lib/finchfs.c
@@ -299,6 +299,9 @@ finchfs_create_chunk_size(const char *path, int32_t flags, mode_t mode,
 	log_debug("finchfs_create_chunk_size() called path=%s chunk_size=%zu",
 		  path, chunk_size);
 	char *p = canonical_path(path);
+	if (p == NULL) {
+		return (-1);
+	}
 	int ret;
 	int fd;
 	struct finch_file *file;
@@ -352,7 +355,13 @@ int
 finchfs_open(const char *path, int32_t flags)
 {
 	log_debug("finchfs_open() called path=%s", path);
-	char *p = canonical_path(path);
+	char *p = NULL;
+	if (path != NULL) {
+		p = canonical_path(path);
+		if (p == NULL) {
+			return -1;
+		}
+	}
 	int ret;
 	int fd;
 	struct finch_file *file;
@@ -377,6 +386,9 @@ finchfs_open(const char *path, int32_t flags)
 	file->access = flags & 0b11;
 	file->pos = 0;
 	fs_stat_t st;
+	if (path == NULL) {
+		return (fd);
+	}
 	if (flags & __O_DIRECTORY) {
 		ret = fs_rpc_inode_open_dir(NULL, p, file->eid, &st, 1 << 4);
 		if (ret) {
@@ -430,7 +442,8 @@ finchfs_close(int fd)
 		return (-1);
 	}
 	int ret = 0;
-	if (!S_ISDIR(fd_table[fd].file->mode)) {
+	if (fd_table[fd].file->path != NULL &&
+	    !S_ISDIR(fd_table[fd].file->mode)) {
 		ret = fs_rpc_inode_close(
 		    fd_table[fd].file->path, fd_table[fd].file->eid[0],
 		    fd_table[fd].file->access, fd_table[fd].file->size);
@@ -470,6 +483,9 @@ finchfs_pwrite(int fd, const void *buf, size_t size, off_t offset)
 	if (size == 0) {
 		return (0);
 	}
+	if (fd_table[fd].file->path == NULL) {
+		return (size);
+	}
 	log_debug("finchfs_pwrite() called ino=%zu size=%zu offset=%ld",
 		  fd_table[fd].file->i_ino, size, offset);
 	chunk_size = fd_table[fd].file->chunk_size;
@@ -557,6 +573,9 @@ finchfs_pread(int fd, void *buf, size_t size, off_t offset)
 		errno = EINVAL;
 		return (-1);
 	}
+	if (fd_table[fd].file->path == NULL) {
+		return (0);
+	}
 	if (fd_table[fd].file->access == O_WRONLY) {
 		errno = EPERM;
 		return (-1);
@@ -623,7 +642,7 @@ finchfs_read(int fd, void *buf, size_t size)
 {
 	log_debug("finchfs_read() called fd=%d size=%zu", fd, size);
 	ssize_t ret;
-	if (fd < 0 || fd >= fd_table_size || fd_table[fd].file->path == NULL) {
+	if (fd < 0 || fd >= fd_table_size || fd_table[fd].file == NULL) {
 		errno = EBADF;
 		return (-1);
 	}
@@ -668,6 +687,9 @@ finchfs_fsync(int fd)
 		errno = EBADF;
 		return (-1);
 	}
+	if (fd_table[fd].file->path == NULL) {
+		return (0);
+	}
 	int ret;
 	ret = fs_rpc_inode_fsync(fd_table[fd].file->i_ino,
 				 fd_table[fd].file->eid[0],
@@ -681,6 +703,9 @@ finchfs_unlink(const char *path)
 	log_debug("finchfs_unlink() called path=%s", path);
 	int ret;
 	char *p = canonical_path(path);
+	if (p == NULL) {
+		return (-1);
+	}
 	ret = fs_rpc_inode_unlink(NULL, p);
 	free(p);
 	return (ret);
@@ -692,6 +717,9 @@ finchfs_mkdir(const char *path, mode_t mode)
 	log_debug("finchfs_mkdir() called path=%s", path);
 	int ret;
 	char *p = canonical_path(path);
+	if (p == NULL) {
+		return (-1);
+	}
 	mode |= S_IFDIR;
 	ret = fs_rpc_mkdir(NULL, p, mode);
 	free(p);
@@ -704,6 +732,9 @@ finchfs_rmdir(const char *path)
 	log_debug("finchfs_rmdir() called path=%s", path);
 	int ret;
 	char *p = canonical_path(path);
+	if (p == NULL) {
+		return (-1);
+	}
 	ret = fs_rpc_inode_unlink_all(NULL, p);
 	free(p);
 	return (ret);
@@ -714,6 +745,9 @@ finchfs_stat(const char *path, struct stat *st)
 {
 	log_debug("finchfs_stat() called path=%s", path);
 	char *p = canonical_path(path);
+	if (p == NULL) {
+		return (-1);
+	}
 	fs_stat_t fst;
 	int ret;
 	ret = fs_rpc_inode_stat(NULL, p, &fst, 0);
@@ -743,6 +777,10 @@ finchfs_fstat(int fd, struct stat *st)
 		errno = EBADF;
 		return (-1);
 	}
+	if (fd_table[fd].file->path == NULL) {
+		errno = EIO;
+		return (-1);
+	}
 	st->st_mode = fd_table[fd].file->mode;
 	st->st_uid = getuid();
 	st->st_gid = getgid();
@@ -763,6 +801,9 @@ finchfs_readdir(const char *path, void *buf,
 	log_debug("finchfs_readdir() called path=%s", path);
 	int ret;
 	char *p = canonical_path(path);
+	if (p == NULL) {
+		return (-1);
+	}
 	ret = fs_rpc_readdir(p, buf, filler);
 	free(p);
 	return (ret);
@@ -776,6 +817,9 @@ finchfs_rename(const char *oldpath, const char *newpath)
 	int ret;
 	char *oldp = canonical_path(oldpath);
 	char *newp = canonical_path(newpath);
+	if (oldp == NULL || newp == NULL) {
+		return (-1);
+	}
 	fs_stat_t st;
 	ret = fs_rpc_inode_stat(NULL, oldp, &st, 0);
 	if (ret) {
@@ -804,6 +848,9 @@ finchfs_find(const char *path, const char *query,
 	log_debug("finchfs_find() called path=%s query=%s", path, query);
 	int ret;
 	char *p = canonical_path(path);
+	if (p == NULL) {
+		return (-1);
+	}
 	ret = fs_rpc_find(p, query, param, buf, filler);
 	free(p);
 	return (ret);
@@ -836,6 +883,9 @@ finchfs_createat_chunk_size(int dirfd, const char *pathname, int flags,
 		eid = fd_table[dirfd].file->eid;
 	}
 	char *p = canonical_path(pathname);
+	if (p == NULL) {
+		return (-1);
+	}
 	int ret;
 	int fd;
 	struct finch_file *file;
@@ -898,6 +948,9 @@ finchfs_openat(int dirfd, const char *pathname, int flags)
 		eid = fd_table[dirfd].file->eid;
 	}
 	char *p = canonical_path(pathname);
+	if (p == NULL) {
+		return (-1);
+	}
 	int ret;
 	int fd;
 	struct finch_file *file;
@@ -981,6 +1034,9 @@ finchfs_fstatat(int dirfd, const char *pathname, struct stat *st, int flags)
 		eid = fd_table[dirfd].file->eid;
 	}
 	char *p = canonical_path(pathname);
+	if (p == NULL) {
+		return (-1);
+	}
 	fs_stat_t fst;
 	int ret;
 	ret = fs_rpc_inode_stat(eid, p, &fst, 0);
@@ -1018,6 +1074,9 @@ finchfs_mkdirat(int dirfd, const char *pathname, mode_t mode)
 	}
 	int ret;
 	char *p = canonical_path(pathname);
+	if (p == NULL) {
+		return (-1);
+	}
 	mode |= S_IFDIR;
 	ret = fs_rpc_mkdir(eid, p, mode);
 	free(p);
@@ -1041,6 +1100,9 @@ finchfs_unlinkat(int dirfd, const char *pathname, int flags)
 	}
 	int ret;
 	char *p = canonical_path(pathname);
+	if (p == NULL) {
+		return (-1);
+	}
 	if (flags & AT_REMOVEDIR) {
 		ret = fs_rpc_inode_unlink_all(eid, p);
 	} else {
@@ -1080,6 +1142,9 @@ finchfs_renameat(int olddirfd, const char *oldpath, int newdirfd,
 	int ret;
 	char *oldp = canonical_path(oldpath);
 	char *newp = canonical_path(newpath);
+	if (oldp == NULL || newp == NULL) {
+		return (-1);
+	}
 	fs_stat_t st;
 	ret = fs_rpc_inode_stat(oldeid, oldp, &st, 0);
 	if (ret) {
@@ -1108,6 +1173,10 @@ finchfs_getdents(int fd, void *dirp, size_t count)
 		errno = EBADF;
 		return (-1);
 	}
+	if (fd_table[fd].file->path == NULL) {
+		errno = ENOTDIR;
+		return (-1);
+	}
 	if (!S_ISDIR(fd_table[fd].file->mode)) {
 		errno = ENOTDIR;
 		return (-1);
diff --git a/lib/path.c b/lib/path.c
index 477122a..af54558 100644
--- a/lib/path.c
+++ b/lib/path.c
@@ -46,6 +46,11 @@ canonical_path(const char *path)
 	const char *p = path;
 	char *pp;
 
+	if (path == NULL) {
+		errno = EINVAL;
+		return (NULL);
+	}
+
 	p = skip_slash(p);
 	while (*p) {
 		if (depth >= MAX_DEPTH) {
diff --git a/tests/finchfs_test.cc b/tests/finchfs_test.cc
index 92c6b4f..65f681e 100644
--- a/tests/finchfs_test.cc
+++ b/tests/finchfs_test.cc
@@ -1080,6 +1080,19 @@ TEST(FinchfsTest, Dup2)
 	EXPECT_EQ(finchfs_term(), 0);
 }
 
+TEST(FinchfsTest, DEV_NULL)
+{
+	EXPECT_EQ(finchfs_init(NULL), 0);
+	int fd;
+	fd = finchfs_open(NULL, O_RDWR);
+	EXPECT_EQ(fd, 0);
+	char buf[1024];
+	EXPECT_EQ(finchfs_write(fd, buf, 1024), 1024);
+	EXPECT_EQ(finchfs_read(fd, buf, 1024), 0);
+	EXPECT_EQ(finchfs_close(fd), 0);
+	EXPECT_EQ(finchfs_term(), 0);
+}
+
 static int
 path_to_target_hash(const char *path, int div)
 {