From e7024fb5b4d2eaa9a287dc58bc68467f9d979893 Mon Sep 17 00:00:00 2001
From: Ivan Grokhotkov <igrokhotkov@gmail.com>
Date: Thu, 10 Dec 2015 23:25:54 +0300
Subject: [PATCH] SPIFFS: check if path length is valid (#1089)

---
 cores/esp8266/spiffs_api.cpp | 39 +++++++++++++++++++++++++++++++++---
 1 file changed, 36 insertions(+), 3 deletions(-)

diff --git a/cores/esp8266/spiffs_api.cpp b/cores/esp8266/spiffs_api.cpp
index f1689cbfe..f189b4d4e 100644
--- a/cores/esp8266/spiffs_api.cpp
+++ b/cores/esp8266/spiffs_api.cpp
@@ -41,11 +41,13 @@ extern int32_t spiffs_hal_write(uint32_t addr, uint32_t size, uint8_t *src);
 extern int32_t spiffs_hal_erase(uint32_t addr, uint32_t size);
 extern int32_t spiffs_hal_read(uint32_t addr, uint32_t size, uint8_t *dst);
 
-int getSpiffsMode(OpenMode openMode, AccessMode accessMode);
+static int getSpiffsMode(OpenMode openMode, AccessMode accessMode);
+static bool isSpiffsFilenameValid(const char* name);
 
 class SPIFFSFileImpl;
 class SPIFFSDirImpl;
 
+
 class SPIFFSImpl : public FSImpl {
 public:
     SPIFFSImpl(uint32_t start, uint32_t size, uint32_t pageSize, uint32_t blockSize, uint32_t maxOpenFds)
@@ -63,6 +65,14 @@ public:
     DirImplPtr openDir(const char* path) override;
 
     bool rename(const char* pathFrom, const char* pathTo) override {
+        if (!isSpiffsFilenameValid(pathFrom)) {
+            DEBUGV("SPIFFSImpl::rename: invalid pathFrom=`%s`\r\n", path);
+            return false;
+        }
+        if (!isSpiffsFilenameValid(pathTo)) {
+            DEBUGV("SPIFFSImpl::rename: invalid pathTo=`%s` \r\n", path);
+            return false;
+        }
         auto rc = SPIFFS_rename(&_fs, pathFrom, pathTo);
         if (rc != SPIFFS_OK) {
             DEBUGV("SPIFFS_rename: rc=%d, from=`%s`, to=`%s`\r\n", rc,
@@ -86,6 +96,10 @@ public:
     }
 
     bool remove(const char* path) override {
+        if (!isSpiffsFilenameValid(path)) {
+            DEBUGV("SPIFFSImpl::remove: invalid path=`%s`\r\n", path);
+            return false;
+        }
         auto rc = SPIFFS_remove(&_fs, path);
         if (rc != SPIFFS_OK) {
             DEBUGV("SPIFFS_remove: rc=%d path=`%s`\r\n", rc, path);
@@ -229,7 +243,7 @@ protected:
     std::unique_ptr<uint8_t[]> _cacheBuf;
 };
 
-#define CHECKFD() while (_fd == 0) { DEBUGV("SPIFFSFileImpl(%d) _fd == 0\r\n", __LINE__); abort(); }
+#define CHECKFD() while (_fd == 0) { panic(); }
 
 class SPIFFSFileImpl : public FileImpl {
 public:
@@ -408,6 +422,10 @@ protected:
 
 
 FileImplPtr SPIFFSImpl::open(const char* path, OpenMode openMode, AccessMode accessMode) {
+    if (!isSpiffsFilenameValid(path)) {
+        DEBUGV("SPIFFSImpl::open: invalid path=`%s` \r\n", path);
+        return FileImplPtr();
+    }
     int mode = getSpiffsMode(openMode, accessMode);
     int fd = SPIFFS_open(&_fs, path, mode, 0);
     if (fd < 0 && _fs.err_code == SPIFFS_ERR_DELETED && (openMode & OM_CREATE)) {
@@ -430,12 +448,20 @@ FileImplPtr SPIFFSImpl::open(const char* path, OpenMode openMode, AccessMode acc
 }
 
 bool SPIFFSImpl::exists(const char* path) {
+    if (!isSpiffsFilenameValid(path)) {
+        DEBUGV("SPIFFSImpl::exists: invalid path=`%s` \r\n", path);
+        return false;
+    }
     spiffs_stat stat;
     int rc = SPIFFS_stat(&_fs, path, &stat);
     return rc == SPIFFS_OK;
 }
 
 DirImplPtr SPIFFSImpl::openDir(const char* path) {
+    if (!isSpiffsFilenameValid(path)) {
+        DEBUGV("SPIFFSImpl::openDir: invalid path=`%s` \r\n", path);
+        return DirImplPtr();
+    }
     spiffs_DIR dir;
     spiffs_DIR* result = SPIFFS_opendir(&_fs, path, &dir);
     if (!result) {
@@ -445,7 +471,7 @@ DirImplPtr SPIFFSImpl::openDir(const char* path) {
     return std::make_shared<SPIFFSDirImpl>(path, this, dir);
 }
 
-int getSpiffsMode(OpenMode openMode, AccessMode accessMode) {
+static int getSpiffsMode(OpenMode openMode, AccessMode accessMode) {
     int mode = 0;
     if (openMode & OM_CREATE) {
         mode |= SPIFFS_CREAT;
@@ -465,6 +491,13 @@ int getSpiffsMode(OpenMode openMode, AccessMode accessMode) {
     return mode;
 }
 
+static bool isSpiffsFilenameValid(const char* name) {
+    if (name == nullptr)
+        return false;
+    auto len = strlen(name);
+    return len > 0 && len <= SPIFFS_OBJ_NAME_LEN;
+}
+
 // these symbols should be defined in the linker script for each flash layout
 extern "C" uint32_t _SPIFFS_start;
 extern "C" uint32_t _SPIFFS_end;