commit 0b1ad230708636516064a6af14cb111fb3b5d10d
author Tianjie Xu <xunchang@google.com> Tue Apr 11 19:55:28 2017 +0000
committer android-build-merger <android-build-merger@google.com> Tue Apr 11 19:55:28 2017 +0000
tree fb05e74e6a631650673667b12361ccfb0f2be29a
parent c740d0b56c1ceea761a84044dab86c2d681cf275
parent afddaba0cced573381b8310ac9b6f40a93f22703

Fix out of bound read in libziparchive am: d9fd1863f4 am: 6908996434 am: 25c0d68d29 am: ed33065bfc am: bc8c8e4b56
am: afddaba0cc

Change-Id: Ie8f3874506403c092719f595fa7fb2402c6ecf36

libziparchive/zip_archive.cc

diff --git a/libziparchive/zip_archive.cc b/libziparchive/zip_archive.cc
index 986ee72..49097ce 100644
--- a/libziparchive/zip_archive.cc
+++ b/libziparchive/zip_archive.cc
@@ -386,6 +386,14 @@
   const uint8_t* const cd_end = cd_ptr + cd_length;
   const uint8_t* ptr = cd_ptr;
   for (uint16_t i = 0; i < num_entries; i++) {
+    if (ptr > cd_end - sizeof(CentralDirectoryRecord)) {
+      ALOGW("Zip: ran off the end (at %" PRIu16 ")", i);
+#if defined(__ANDROID__)
+      android_errorWriteLog(0x534e4554, "36392138");
+#endif
+      return -1;
+    }
+
     const CentralDirectoryRecord* cdr =
         reinterpret_cast<const CentralDirectoryRecord*>(ptr);
     if (cdr->record_signature != CentralDirectoryRecord::kSignature) {
@@ -393,11 +401,6 @@
       return -1;
     }
 
-    if (ptr + sizeof(CentralDirectoryRecord) > cd_end) {
-      ALOGW("Zip: ran off the end (at %" PRIu16 ")", i);
-      return -1;
-    }
-
     const off64_t local_header_offset = cdr->local_file_header_offset;
     if (local_header_offset >= archive->directory_offset) {
       ALOGW("Zip: bad LFH offset %" PRId64 " at entry %" PRIu16,