wifi: Clear ring bufffers on detecting buffer corruption

While appending the newly received buffer to ring buffer list,
check the size of the first buffer in the ring buffer list.
If it is invalid(zero size or exceeding the max allowed size),
return failure & clear all the ring buffers.

Bug: 232477451
Test: vts test - 1.6/default/tests/runtests.sh
Test: Manual - Ran basic wifi tests & checked bugreports

Change-Id: Iaa41262f534914b971fe178053f1974248a46e70

3 files changed, 31 insertions, 5 deletions

diff --git a/wifi/1.6/default/ringbuffer.cpp b/wifi/1.6/default/ringbuffer.cpp
index 6d4ed843c3..981bf7bce7 100644
--- a/wifi/1.6/default/ringbuffer.cpp
+++ b/wifi/1.6/default/ringbuffer.cpp
@@ -26,20 +26,26 @@ namespace implementation {
 
 Ringbuffer::Ringbuffer(size_t maxSize) : size_(0), maxSize_(maxSize) {}
 
-void Ringbuffer::append(const std::vector<uint8_t>& input) {
+enum Ringbuffer::AppendStatus Ringbuffer::append(const std::vector<uint8_t>& input) {
     if (input.size() == 0) {
-        return;
+        return AppendStatus::FAIL_IP_BUFFER_ZERO;
     }
     if (input.size() > maxSize_) {
         LOG(INFO) << "Oversized message of " << input.size() << " bytes is dropped";
-        return;
+        return AppendStatus::FAIL_IP_BUFFER_EXCEEDED_MAXSIZE;
     }
     data_.push_back(input);
     size_ += input.size() * sizeof(input[0]);
     while (size_ > maxSize_) {
+        if (data_.front().size() <= 0 || data_.front().size() > maxSize_) {
+            LOG(ERROR) << "First buffer in the ring buffer is Invalid. Size: "
+                       << data_.front().size();
+            return AppendStatus::FAIL_RING_BUFFER_CORRUPTED;
+        }
         size_ -= data_.front().size() * sizeof(data_.front()[0]);
         data_.pop_front();
     }
+    return AppendStatus::SUCCESS;
 }
 
 const std::list<std::vector<uint8_t>>& Ringbuffer::getData() const {
diff --git a/wifi/1.6/default/ringbuffer.h b/wifi/1.6/default/ringbuffer.h
index 8571a9f3d4..c6a1e4c52d 100644
--- a/wifi/1.6/default/ringbuffer.h
+++ b/wifi/1.6/default/ringbuffer.h
@@ -31,11 +31,19 @@ namespace implementation {
  */
 class Ringbuffer {
   public:
+    // Error codes for the append ring buffer operation
+    enum AppendStatus {
+        SUCCESS,
+        FAIL_GENERIC,
+        FAIL_IP_BUFFER_ZERO,
+        FAIL_IP_BUFFER_EXCEEDED_MAXSIZE,
+        FAIL_RING_BUFFER_CORRUPTED
+    };
     explicit Ringbuffer(size_t maxSize);
 
     // Appends the data buffer and deletes from the front until buffer is
     // within |maxSize_|.
-    void append(const std::vector<uint8_t>& input);
+    enum AppendStatus append(const std::vector<uint8_t>& input);
     const std::list<std::vector<uint8_t>>& getData() const;
     void clear();
 
diff --git a/wifi/1.6/default/wifi_chip.cpp b/wifi/1.6/default/wifi_chip.cpp
index f062409d4e..c7c00b17fd 100644
--- a/wifi/1.6/default/wifi_chip.cpp
+++ b/wifi/1.6/default/wifi_chip.cpp
@@ -1613,6 +1613,7 @@ WifiStatus WifiChip::registerDebugRingBufferCallback() {
                     return;
                 }
                 WifiDebugRingBufferStatus hidl_status;
+                Ringbuffer::AppendStatus appendstatus;
                 if (!hidl_struct_util::convertLegacyDebugRingBufferStatusToHidl(status,
                                                                                 &hidl_status)) {
                     LOG(ERROR) << "Error converting ring buffer status";
@@ -1623,13 +1624,19 @@ WifiStatus WifiChip::registerDebugRingBufferCallback() {
                     const auto& target = shared_ptr_this->ringbuffer_map_.find(name);
                     if (target != shared_ptr_this->ringbuffer_map_.end()) {
                         Ringbuffer& cur_buffer = target->second;
-                        cur_buffer.append(data);
+                        appendstatus = cur_buffer.append(data);
                     } else {
                         LOG(ERROR) << "Ringname " << name << " not found";
                         return;
                     }
                     // unique_lock unlocked here
                 }
+                if (appendstatus == Ringbuffer::AppendStatus::FAIL_RING_BUFFER_CORRUPTED) {
+                    LOG(ERROR) << "Ringname " << name << " is corrupted. Clear the ring buffer";
+                    shared_ptr_this->writeRingbufferFilesInternal();
+                    return;
+                }
+
             };
     legacy_hal::wifi_error legacy_status = legacy_hal_.lock()->registerRingBufferCallbackHandler(
             getFirstActiveWlanIfaceName(), on_ring_buffer_data_callback);
@@ -1971,6 +1978,11 @@ bool WifiChip::writeRingbufferFilesInternal() {
             }
             unique_fd file_auto_closer(dump_fd);
             for (const auto& cur_block : cur_buffer.getData()) {
+                if (cur_block.size() <= 0 || cur_block.size() > kMaxBufferSizeBytes) {
+                    PLOG(ERROR) << "Ring buffer: " << item.first
+                                << " is corrupted. Invalid block size: " << cur_block.size();
+                    break;
+                }
                 if (write(dump_fd, cur_block.data(), sizeof(cur_block[0]) * cur_block.size()) ==
                     -1) {
                     PLOG(ERROR) << "Error writing to file";