Improve log_buffer_get_* exceptional conditions

We now handle the case in which the struct lacks the ending '\0'.
This would mean that one could read past the end of the struct while
using the result.

Change-Id: Ie70ffd57181dd351ab94db27550b8f967235648f

diff --git a/src/shared/logprint.c b/src/shared/logprint.c
index f822aad..8782b6d 100644 (file)
--- a/src/shared/logprint.c
+++ b/src/shared/logprint.c
@@ -539,10 +539,14 @@ int log_add_filter_tid(log_filter *p_filter, pthread_t tid)
  */
 const char* log_buffer_get_tag(const struct dlogutil_entry *entry)
 {
+       assert(entry);
+
        if (entry->len - (int) sizeof(struct dlogutil_entry) < 2)
                return NULL;
+       if (((const char *)entry)[entry->len - 1] != '\0')
+               return NULL;
 
-       return (char*)entry->msg;
+       return entry->msg;
 }
 
 /**
@@ -553,10 +557,14 @@ const char* log_buffer_get_tag(const struct dlogutil_entry *entry)
  */
 const char* log_buffer_get_message(const struct dlogutil_entry *entry)
 {
+       assert(entry);
+
        if (entry->len - (int) sizeof(struct dlogutil_entry) < 2)
                return NULL;
+       if (((const char *)entry)[entry->len - 1] != '\0')
+               return NULL;
 
-       return (char*)entry->msg + entry->tag_len + 1 /* NULL delimiter */;
+       return entry->msg + entry->tag_len + 1 /* NULL delimiter */;
 }
 
 enum dlogutil_sorting_order get_format_sorting(log_print_format format)