Fix potential buffer overrun. am: 38025bc7fa am: 805b415be6

am: 0e17e18496

* commit '0e17e1849633b07c019daf89c0d2ededc1333f3b':
  Fix potential buffer overrun.

Change-Id: I2d0f7e326f21fd0fd2e8f03b2c7eda302730f4f9

1 files changed, 5 insertions, 5 deletions

diff --git a/libdex/OptInvocation.cpp b/libdex/OptInvocation.cpp
index 031ec9177..a9ea3a2d5 100644
--- a/libdex/OptInvocation.cpp
+++ b/libdex/OptInvocation.cpp
@@ -89,9 +89,9 @@ char* dexOptGenerateCacheFileName(const char* fileName, const char* subFileName)
             ALOGE("Can't get CWD while opening jar file");
             return NULL;
         }
-        strncat(absoluteFile, "/", kBufLen);
+        strncat(absoluteFile, "/", kBufLen - strlen(absoluteFile));
     }
-    strncat(absoluteFile, fileName, kBufLen);
+    strncat(absoluteFile, fileName, kBufLen - strlen(absoluteFile));
 
     /*
      * Append the name of the Jar file entry, if any.  This is not currently
@@ -99,8 +99,8 @@ char* dexOptGenerateCacheFileName(const char* fileName, const char* subFileName)
      * in a Jar.
      */
     if (subFileName != NULL) {
-        strncat(absoluteFile, "/", kBufLen);
-        strncat(absoluteFile, subFileName, kBufLen);
+        strncat(absoluteFile, "/", kBufLen - strlen(absoluteFile));
+        strncat(absoluteFile, subFileName, kBufLen - strlen(absoluteFile));
     }
 
     /* Turn the path into a flat filename by replacing
@@ -138,7 +138,7 @@ char* dexOptGenerateCacheFileName(const char* fileName, const char* subFileName)
 
     /* Tack on the file name for the actual cache file path.
      */
-    strncat(nameBuf, absoluteFile, kBufLen);
+    strncat(nameBuf, absoluteFile, kBufLen - strlen(nameBuf));
 
     ALOGV("Cache file for '%s' '%s' is '%s'", fileName, subFileName, nameBuf);
     return strdup(nameBuf);