commit 305374cf0f8cf28b58a108cf4f45df92fc0dde86
author Mark Salyzyn <salyzyn@google.com> Thu Aug 18 14:59:41 2016 -0700
committer Mark Salyzyn <salyzyn@google.com> Tue Aug 23 14:51:50 2016 -0700
tree 4f7ae56a180ae568508f5da1f4f83e25a054d712
parent 82b67fff06363c8e7a17058cb5ce748f21a27f11

logger: validate hdr_size field in logger entry

- check hdr_size to make sure it is in the expected range
  from sizeof entry_v1 to entry (entry_v4).
- alter msg() method to report NULL on invalid hdr_size
- alter all users of msg() method.

Bug: 30947841
Change-Id: I9bc1740d7aa9f37df5be966c18de1fb9de63d5dd

liblog/tests/liblog_benchmark.cpp

diff --git a/liblog/tests/liblog_benchmark.cpp b/liblog/tests/liblog_benchmark.cpp
index 1b66a56..f4e3089 100644
--- a/liblog/tests/liblog_benchmark.cpp
+++ b/liblog/tests/liblog_benchmark.cpp
@@ -542,7 +542,7 @@
 
             char* eventData = log_msg.msg();
 
-            if (eventData[4] != EVENT_TYPE_LONG) {
+            if (!eventData || (eventData[4] != EVENT_TYPE_LONG)) {
                 continue;
             }
             log_time tx(eventData + 4 + 1);
@@ -622,7 +622,7 @@
 
             char* eventData = log_msg.msg();
 
-            if (eventData[4] != EVENT_TYPE_LONG) {
+            if (!eventData || (eventData[4] != EVENT_TYPE_LONG)) {
                 continue;
             }
             log_time tx(eventData + 4 + 1);

liblog/tests/liblog_test.cpp

diff --git a/liblog/tests/liblog_test.cpp b/liblog/tests/liblog_test.cpp
index df2c766..8f6f07a 100644
--- a/liblog/tests/liblog_test.cpp
+++ b/liblog/tests/liblog_test.cpp
@@ -154,7 +154,7 @@
 
         char *eventData = log_msg.msg();
 
-        if (eventData[4] != EVENT_TYPE_LONG) {
+        if (!eventData || (eventData[4] != EVENT_TYPE_LONG)) {
             continue;
         }
 
@@ -227,7 +227,7 @@
 
         char *eventData = log_msg.msg();
 
-        if (eventData[4] != EVENT_TYPE_STRING) {
+        if (!eventData || (eventData[4] != EVENT_TYPE_STRING)) {
             continue;
         }
 
@@ -506,7 +506,7 @@
 
         char *eventData = log_msg.msg();
 
-        if (eventData[4] != EVENT_TYPE_LONG) {
+        if (!eventData || (eventData[4] != EVENT_TYPE_LONG)) {
             continue;
         }
 
@@ -637,7 +637,7 @@
 
         char *eventData = log_msg.msg();
 
-        if (eventData[4] != EVENT_TYPE_LONG) {
+        if (!eventData || (eventData[4] != EVENT_TYPE_LONG)) {
             continue;
         }
 
@@ -788,7 +788,7 @@
 
         char *eventData = log_msg.msg();
 
-        if (eventData[4] != EVENT_TYPE_LONG) {
+        if (!eventData || (eventData[4] != EVENT_TYPE_LONG)) {
             continue;
         }
 
@@ -990,9 +990,9 @@
             continue;
         }
 
-        char *data = log_msg.msg() + 1;
+        char *data = log_msg.msg();
 
-        if (strcmp(data, tag)) {
+        if (!data || strcmp(++data, tag)) {
             continue;
         }
 
@@ -1107,9 +1107,9 @@
             continue;
         }
 
-        char *data = log_msg.msg() + 1;
+        char *data = log_msg.msg();
 
-        if (strcmp(data, tag)) {
+        if (!data || strcmp(++data, tag)) {
             continue;
         }
 
@@ -1606,6 +1606,9 @@
         }
 
         char *eventData = log_msg.msg();
+        if (!eventData) {
+            continue;
+        }
 
         // Tag
         int tag = get4LE(eventData);
@@ -1687,6 +1690,10 @@
         }
 
         char *eventData = log_msg.msg();
+        if (!eventData) {
+            continue;
+        }
+
         char *original = eventData;
 
         // Tag
@@ -1774,6 +1781,9 @@
         }
 
         char *eventData = log_msg.msg();
+        if (!eventData) {
+            continue;
+        }
 
         // Tag
         int tag = get4LE(eventData);
@@ -1817,6 +1827,9 @@
         }
 
         char *eventData = log_msg.msg();
+        if (!eventData) {
+            continue;
+        }
 
         // Tag
         int tag = get4LE(eventData);
@@ -1904,6 +1917,9 @@
         }
 
         char *eventData = log_msg.msg();
+        if (!eventData) {
+            continue;
+        }
 
         // Tag
         int tag = get4LE(eventData);
@@ -1961,6 +1977,9 @@
         }
 
         char *eventData = log_msg.msg();
+        if (!eventData) {
+            continue;
+        }
 
         // Tag
         int tag = get4LE(eventData);
@@ -2449,16 +2468,19 @@
         android_log_format_free(logformat);
 
         // test buffer reading API
-        snprintf(msgBuf, sizeof(msgBuf), "I/[%d]", get4LE(eventData));
-        print_barrier();
-        fprintf(stderr, "%-10s(%5u): ", msgBuf, pid);
-        memset(msgBuf, 0, sizeof(msgBuf));
-        int buffer_to_string = android_log_buffer_to_string(
-            eventData + sizeof(uint32_t),
-            log_msg.entry.len - sizeof(uint32_t),
-            msgBuf, sizeof(msgBuf));
-        fprintf(stderr, "%s\n", msgBuf);
-        print_barrier();
+        int buffer_to_string = -1;
+        if (eventData) {
+            snprintf(msgBuf, sizeof(msgBuf), "I/[%d]", get4LE(eventData));
+            print_barrier();
+            fprintf(stderr, "%-10s(%5u): ", msgBuf, pid);
+            memset(msgBuf, 0, sizeof(msgBuf));
+            buffer_to_string = android_log_buffer_to_string(
+                eventData + sizeof(uint32_t),
+                log_msg.entry.len - sizeof(uint32_t),
+                msgBuf, sizeof(msgBuf));
+            fprintf(stderr, "%s\n", msgBuf);
+            print_barrier();
+        }
         EXPECT_EQ(0, buffer_to_string);
         EXPECT_EQ(strlen(expected_string), strlen(msgBuf));
         EXPECT_EQ(0, strcmp(expected_string, msgBuf));