Pull request #4880: decompress: Fixed VBA decompression unhandled mem alloc exception

Merge in SNORT/snort3 from ~ASHUGUP3/snort3:bug_CSCwq23369 to master

Squashed commit of the following:

commit 8030f6c95bc15dad06a4b52d71f7a2b37f9d9603
Author: ashutosh <ashugup3@cisco.com>
Date:   Tue Aug 26 12:28:53 2025 +0530

    decompress: Fixed VBA decompression unhandled mem alloc exception

diff --git a/src/decompress/file_olefile.cc b/src/decompress/file_olefile.cc
index 53a19620b8723a9d3bdab22696dd9a9386dbe55d..b4659491bcfd193966c52a3da9e01f4bb46c2b24 100644 (file)
--- a/src/decompress/file_olefile.cc
+++ b/src/decompress/file_olefile.cc
@@ -301,7 +301,19 @@ void OleFile :: get_file_data(FileProperty* node, uint8_t*& file_data, uint32_t&
         starting_sector = node->get_starting_sector();
         stream_size = node->get_stream_size();
 
-        file_data = new uint8_t[stream_size];
+        if (stream_size == 0 || stream_size > MAX_STREAM_SIZE) {
+            VBA_DEBUG(vba_data_trace, DEFAULT_TRACE_OPTION_ID, TRACE_ERROR_LEVEL, CURRENT_PACKET,
+                "Requested stream_size %u is invalid or too large (max %u). Allocation aborted.\n", stream_size, MAX_STREAM_SIZE);
+            file_data = nullptr;
+            return;
+        }
+
+        file_data = new (std::nothrow) uint8_t[stream_size];
+        if (!file_data) {
+            VBA_DEBUG(vba_data_trace, DEFAULT_TRACE_OPTION_ID, TRACE_ERROR_LEVEL, CURRENT_PACKET,
+                "Memory allocation failed for stream_size %u.\n", stream_size);
+            return;
+        }
         temp_data = file_data;
         if (stream_size <= header->get_minifat_cutoff())
             is_fat = MINIFAT_SECTOR;
@@ -381,16 +393,23 @@ void OleFile :: populate_fat_list()
     VBA_DEBUG(vba_data_trace, DEFAULT_TRACE_OPTION_ID, TRACE_INFO_LEVEL, CURRENT_PACKET,
         "Reading the FAT list array.\n");
     fat_list_len = ( header->get_fat_sector_count() * header->get_sector_size() ) / 4;
-    if (fat_list_len < 1)
+
+    if (fat_list_len < 1 || fat_list_len > MAX_STREAM_SIZE)
     {
-        VBA_DEBUG(vba_data_trace, DEFAULT_TRACE_OPTION_ID, TRACE_INFO_LEVEL, CURRENT_PACKET,
-            "FAT list array is empty.\n");
+        VBA_DEBUG(vba_data_trace, DEFAULT_TRACE_OPTION_ID, TRACE_ERROR_LEVEL, CURRENT_PACKET,
+            "FAT list length %d is invalid or too large (max %d). Allocation aborted.\n", fat_list_len, MAX_STREAM_SIZE);
+        fat_list = nullptr;
         return;
     }
 
-    fat_list = new int32_t[fat_list_len];
+    fat_list = new (std::nothrow) int32_t[fat_list_len];
+    if (!fat_list) {
+        VBA_DEBUG(vba_data_trace, DEFAULT_TRACE_OPTION_ID, TRACE_ERROR_LEVEL, CURRENT_PACKET,
+            "Memory allocation failed for FAT list length %d.\n", fat_list_len);
+        return;
+    }
 
-    memset(fat_list, -1, fat_list_len);
+    memset(fat_list, -1, fat_list_len * sizeof(int32_t));
 
     current_sector = fat_sector;
     while (current_sector > INVALID_SECTOR)
@@ -444,16 +463,23 @@ void OleFile :: populate_mini_fat_list()
     VBA_DEBUG(vba_data_trace, DEFAULT_TRACE_OPTION_ID, TRACE_INFO_LEVEL, CURRENT_PACKET,
         "Reading the Mini-FAT list array.\n");
     mini_fat_list_len = ( header->get_minifat_count() * header->get_sector_size() )  / 4;
-    if (mini_fat_list_len < 1)
+
+    if (mini_fat_list_len < 1 || mini_fat_list_len > MAX_STREAM_SIZE)
     {
-        VBA_DEBUG(vba_data_trace, DEFAULT_TRACE_OPTION_ID, TRACE_INFO_LEVEL, CURRENT_PACKET,
-            "Mini-FAT list array is empty.\n");
+        VBA_DEBUG(vba_data_trace, DEFAULT_TRACE_OPTION_ID, TRACE_ERROR_LEVEL, CURRENT_PACKET,
+            "Mini-FAT list length %d is invalid or too large (max %d). Allocation aborted.\n", mini_fat_list_len, MAX_STREAM_SIZE);
+        mini_fat_list = nullptr;
         return;
     }
 
-    mini_fat_list = new int32_t[mini_fat_list_len];
+    mini_fat_list = new (std::nothrow) int32_t[mini_fat_list_len];
+    if (!mini_fat_list) {
+        VBA_DEBUG(vba_data_trace, DEFAULT_TRACE_OPTION_ID, TRACE_ERROR_LEVEL, CURRENT_PACKET,
+            "Memory allocation failed for Mini-FAT list length %d.\n", mini_fat_list_len);
+        return;
+    }
 
-    memset(mini_fat_list, -1, mini_fat_list_len);
+    memset(mini_fat_list, -1, mini_fat_list_len * sizeof(int32_t));
 
     current_sector = minifat_sector;
     int32_t minfat_curr_cnt = 0;

diff --git a/src/decompress/file_olefile.h b/src/decompress/file_olefile.h
index 452068f98439a49d90c90eb751573a2c106c04d3..f69a5dbf8da79776c94427a647611aa14ff50449 100644 (file)
--- a/src/decompress/file_olefile.h
+++ b/src/decompress/file_olefile.h
@@ -55,6 +55,7 @@
 #define DIR_STARTING_SEC_OFFSET    116
 #define DIR_STREAM_SIZE_OFFSET     120
 #define DIR_NEXT_ENTR_OFFSET       128
+#define MAX_STREAM_SIZE            838860
 
 #define CURRENT_PACKET snort::DetectionEngine::get_current_packet()