From 37b47b8e47d9d5ad878244ba79cbd4401921f15d Mon Sep 17 00:00:00 2001
From: negativekelvin <negativekelvin@github.com>
Date: Wed, 27 Mar 2019 20:14:56 +0530
Subject: [PATCH] nvs_flash: Multi-page blob erased using nvs_erase_key should
 be cleaned properly

Earlier eraseItem function in Storage class would do lazy cleanup of
multi-page blobs if called using type "ANY" instead of "BLOB". It used to
just delete BLOB data and index would remain as is. Any subsequent read
would delete index entry as well. This however would return a valid
length without error if nvs_get_blob API was just used for finding
length and not reading the complete blob. This change fixes this issue.

Closes https://github.com/espressif/esp-idf/issues/3255
---
 components/nvs_flash/src/nvs_storage.cpp        |  6 ++++++
 components/nvs_flash/test_nvs_host/test_nvs.cpp | 16 ++++++++++++++++
 2 files changed, 22 insertions(+)

diff --git a/components/nvs_flash/src/nvs_storage.cpp b/components/nvs_flash/src/nvs_storage.cpp
index 5cb34b27a..d1b4b01be 100644
--- a/components/nvs_flash/src/nvs_storage.cpp
+++ b/components/nvs_flash/src/nvs_storage.cpp
@@ -593,6 +593,12 @@ esp_err_t Storage::eraseItem(uint8_t nsIndex, ItemType datatype, const char* key
         return err;
     }
 
+#ifdef CONFIG_MP_BLOB_SUPPORT
+    if (item.datatype == ItemType::BLOB_DATA || item.datatype == ItemType::BLOB_IDX) {
+        return eraseMultiPageBlob(nsIndex, key);
+    }
+#endif 
+
     return findPage->eraseItem(nsIndex, datatype, key);
 }
 
diff --git a/components/nvs_flash/test_nvs_host/test_nvs.cpp b/components/nvs_flash/test_nvs_host/test_nvs.cpp
index cbdd3daaf..287c8cb97 100644
--- a/components/nvs_flash/test_nvs_host/test_nvs.cpp
+++ b/components/nvs_flash/test_nvs_host/test_nvs.cpp
@@ -1776,6 +1776,22 @@ TEST_CASE("Modification from  multi-page to single page", "[nvs]")
     nvs_close(handle);
 }
 
+TEST_CASE("Multi-page blob erased using nvs_erase_key should not be found when probed for just length", "[nvs]")
+{
+    const size_t blob_size = Page::CHUNK_MAX_SIZE *3;
+    uint8_t blob[blob_size] = {0};
+    size_t read_size = blob_size;
+    SpiFlashEmulator emu(5);
+    TEST_ESP_OK(nvs_flash_init_custom(NVS_DEFAULT_PART_NAME, 0, 5));
+    nvs_handle handle;
+    TEST_ESP_OK(nvs_open("Test", NVS_READWRITE, &handle));
+    TEST_ESP_OK(nvs_set_blob(handle, "abc", blob, blob_size));
+    TEST_ESP_OK(nvs_erase_key(handle, "abc"));
+    TEST_ESP_ERR(nvs_get_blob(handle, "abc", NULL, &read_size), ESP_ERR_NVS_NOT_FOUND); 
+    TEST_ESP_OK(nvs_commit(handle));
+    nvs_close(handle);
+}
+
 
 TEST_CASE("Check that orphaned blobs are erased during init", "[nvs]")
 {