From 40a66667f72538b37956f6cabbc09dc0c1dd6cf2 Mon Sep 17 00:00:00 2001
From: amenkov <unknown>
Date: Wed, 15 Apr 2020 13:26:38 -0700
Subject: [PATCH] 8241522: Manifest improved jar headers redux Reviewed-by:
 sspitsyn, jwilhelm, mschoene, rhalade, mbalao, andrew

---
 src/share/instrument/EncodingSupport.c   | 6 +++++-
 src/share/instrument/InvocationAdapter.c | 8 ++++++--
 2 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/src/share/instrument/EncodingSupport.c b/src/share/instrument/EncodingSupport.c
index 2e290b721..8261b92ac 100644
--- a/src/share/instrument/EncodingSupport.c
+++ b/src/share/instrument/EncodingSupport.c
@@ -38,7 +38,11 @@ modifiedUtf8LengthOfUtf8(char* string, int length) {
     int i;
 
     new_length = 0;
-    for ( i = 0 ; i < length ; i++ ) {
+    /*
+     * if length < 0 or new_length becomes < 0 => string is too big
+     * (handled as error after the cycle).
+     */
+    for ( i = 0 ; i < length && new_length >= 0 ; i++ ) {
         unsigned byte;
 
         byte = (unsigned char)string[i];
diff --git a/src/share/instrument/InvocationAdapter.c b/src/share/instrument/InvocationAdapter.c
index 7ea4ed377..5aa189b05 100644
--- a/src/share/instrument/InvocationAdapter.c
+++ b/src/share/instrument/InvocationAdapter.c
@@ -206,8 +206,10 @@ Agent_OnLoad(JavaVM *vm, char *tail, void * reserved) {
         /*
          * According to JVMS class name is represented as CONSTANT_Utf8_info,
          * so its length is u2 (i.e. must be <= 0xFFFF).
+         * Negative oldLen or newLen means we got signed integer overflow
+         * (modifiedUtf8LengthOfUtf8 returns negative value if oldLen is negative).
          */
-        if (newLen > 0xFFFF) {
+        if (oldLen < 0 || newLen < 0 || newLen > 0xFFFF) {
             fprintf(stderr, "-javaagent: Premain-Class value is too big\n");
             free(jarfile);
             if (options != NULL) free(options);
@@ -376,8 +378,10 @@ Agent_OnAttach(JavaVM* vm, char *args, void * reserved) {
         /*
          * According to JVMS class name is represented as CONSTANT_Utf8_info,
          * so its length is u2 (i.e. must be <= 0xFFFF).
+         * Negative oldLen or newLen means we got signed integer overflow
+         * (modifiedUtf8LengthOfUtf8 returns negative value if oldLen is negative).
          */
-        if (newLen > 0xFFFF) {
+        if (oldLen < 0 || newLen < 0 || newLen > 0xFFFF) {
             fprintf(stderr, "Agent-Class value is too big\n");
             free(jarfile);
             if (options != NULL) free(options);
-- 
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