Changeset 91091 in vbox

Timestamp:

Sep 2, 2021 1:06:51 PM (3 years ago)

Author:

vboxsync

Message:

Runtime/vfs/vfsmemory.cpp: Fix a bug causing the extent lookup to fail if the file starts with zeroes and the offset for the lookup falls into that area, fix a second bug in the write code where the zeros in the source buffer are not skipped leading to data corruption

File:

• trunk/src/VBox/Runtime/common/vfs/vfsmemory.cpp (modified) (2 diffs)

trunk/src/VBox/Runtime/common/vfs/vfsmemory.cpp

@@ -172 +172 @@
     if (!pExtent || off < pExtent->off)
     {
+        /* Check whether the offset is before the first extent first. */
+        pExtent = RTListGetFirst(&pThis->ExtentHead, RTVFSMEMEXTENT, Entry);
+        if (   pExtent
+            && off < pExtent->off)
+        {
+            *pfHit = false;
+            return pExtent;
+        }
+
         /* Consider the last entry first (for writes). */
         pExtent = RTListGetLast(&pThis->ExtentHead, RTVFSMEMEXTENT, Entry);
@@ -484 +493 @@
                 if (!cbLeftToWrite)
                     break;
+                pbSrc += cbZeros;
 
                 Assert(!pExtent || offUnsigned <= pExtent->off);