Disk Cache: Discard entries from ReadData if something is clearly wrong.

BUG=107457
TEST=net_unittests

Review URL: http://codereview.chromium.org/8913013

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@114740 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 38 insertions, 2 deletions

diff --git a/net/disk_cache/entry_impl.cc b/net/disk_cache/entry_impl.cc
index 7e13029..b0226a7 100644
--- a/net/disk_cache/entry_impl.cc
+++ b/net/disk_cache/entry_impl.cc
@@ -974,12 +974,16 @@ int EntryImpl::InternalReadData(int index, int offset, net::IOBuffer* buf,
 
   address.set_value(entry_.Data()->data_addr[index]);
   DCHECK(address.is_initialized());
-  if (!address.is_initialized())
+  if (!address.is_initialized()) {
+    DoomImpl();
     return net::ERR_FAILED;
+  }
 
   File* file = GetBackingFile(address, index);
-  if (!file)
+  if (!file) {
+    DoomImpl();
     return net::ERR_FAILED;
+  }
 
   size_t file_offset = offset;
   if (address.is_block_file()) {
@@ -1000,6 +1004,7 @@ int EntryImpl::InternalReadData(int index, int offset, net::IOBuffer* buf,
   if (!file->Read(buf->data(), buf_len, file_offset, io_callback, &completed)) {
     if (io_callback)
       io_callback->Discard();
+    DoomImpl();
     return net::ERR_FAILED;
   }
 
diff --git a/net/disk_cache/entry_unittest.cc b/net/disk_cache/entry_unittest.cc
index a763dbb..c537ef1 100644
--- a/net/disk_cache/entry_unittest.cc
+++ b/net/disk_cache/entry_unittest.cc
@@ -3,6 +3,7 @@
 // found in the LICENSE file.
 
 #include "base/basictypes.h"
+#include "base/file_util.h"
 #include "base/threading/platform_thread.h"
 #include "base/timer.h"
 #include "base/string_util.h"
@@ -1244,6 +1245,36 @@ TEST_F(DiskCacheEntryTest, MemoryOnlyDoomedEntry) {
   DoomedEntry();
 }
 
+// Tests that we discard entries if the data is missing.
+TEST_F(DiskCacheEntryTest, MissingData) {
+  SetDirectMode();
+  InitCache();
+
+  std::string key("the first key");
+  disk_cache::Entry* entry;
+  ASSERT_EQ(net::OK, CreateEntry(key, &entry));
+
+  // Write to an external file.
+  const int kSize = 20000;
+  scoped_refptr<net::IOBuffer> buffer(new net::IOBuffer(kSize));
+  CacheTestFillBuffer(buffer->data(), kSize, false);
+  EXPECT_EQ(kSize, WriteData(entry, 0, 0, buffer, kSize, false));
+  entry->Close();
+  FlushQueueForTest();
+
+  disk_cache::Addr address(0x80000001);
+  FilePath name = cache_impl_->GetFileName(address);
+  EXPECT_TRUE(file_util::Delete(name, false));
+
+  // Attempt to read the data.
+  ASSERT_EQ(net::OK, OpenEntry(key, &entry));
+  EXPECT_EQ(net::ERR_FAILED, ReadData(entry, 0, 0, buffer, kSize));
+  entry->Close();
+
+  // The entry should be gone.
+  ASSERT_NE(net::OK, OpenEntry(key, &entry));
+}
+
 // Test that child entries in a memory cache backend are not visible from
 // enumerations.
 TEST_F(DiskCacheEntryTest, MemoryOnlyEnumerationWithSparseEntries) {