From ef677309f49f6c82e98a685105160fb0dc7ebf8d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Rafa=C5=82=20Wojdy=C5=82a?= <omeg@invisiblethingslab.com>
Date: Mon, 2 Dec 2019 11:58:14 +0100
Subject: [PATCH] PF mmap: disallow 0 size

---
 Pal/src/host/Linux-SGX/db_files.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/Pal/src/host/Linux-SGX/db_files.c b/Pal/src/host/Linux-SGX/db_files.c
index 4d18cfba..8d2e4227 100644
--- a/Pal/src/host/Linux-SGX/db_files.c
+++ b/Pal/src/host/Linux-SGX/db_files.c
@@ -349,6 +349,10 @@ static int file_delete(PAL_HANDLE handle, int access) {
 static int pf_file_map(struct protected_file* pf, PAL_HANDLE handle, void** addr, int prot,
                        uint64_t offset, uint64_t size) {
     int fd = handle->file.fd;
+
+    if (size == 0)
+        return -PAL_ERROR_INVAL;
+
     if ((prot & PAL_PROT_READ) && (prot & PAL_PROT_WRITE)) {
         SGX_DBG(DBG_E, "file_map(PF fd %d): trying to map with R+W access\n", fd);
         return -PAL_ERROR_NOTSUPPORT;