From a2cdf73fa34cf196b08932841d107a82c5bc16e5 Mon Sep 17 00:00:00 2001
From: Matej Habrnal <mhabrnal@redhat.com>
Date: Mon, 14 Aug 2017 13:34:59 +0200
Subject: [PATCH] koops: add suspicious strings blacklist

Some strings were accidentally considered suspicious.
In this concrete case strings containing "DEBUG" substring.
Since "BUG" and "DEBUG" overlaps and "BUG" is
listed in suspicious string list, kernel DEBUG messages were
recognized as "BUG"s which are kernel oops-es.

Added "DEBUG" string into mentioned new blacklist.

Related to rhbz#1228344

Signed-off-by: Matej Habrnal <mhabrnal@redhat.com>
---
 src/include/libabrt.h |  2 ++
 src/lib/kernel.c      | 60 ++++++++++++++++++++++++++++++++++-----------------
 2 files changed, 42 insertions(+), 20 deletions(-)

diff --git a/src/include/libabrt.h b/src/include/libabrt.h
index 2510a77..5346328 100644
--- a/src/include/libabrt.h
+++ b/src/include/libabrt.h
@@ -125,6 +125,8 @@ char *kernel_tainted_long(const char *tainted_short);
 int koops_hash_str(char hash_str[SHA1_RESULT_LEN*2 + 1], const char *oops_buf);
 #define koops_extract_oopses abrt_koops_extract_oopses
 void koops_extract_oopses(GList **oops_list, char *buffer, size_t buflen);
+#define koops_suspicious_strings_blacklist abrt_koops_suspicious_strings_blacklist
+GList *koops_suspicious_strings_blacklist(void);
 #define koops_print_suspicious_strings abrt_koops_print_suspicious_strings
 void koops_print_suspicious_strings(void);
 /**
diff --git a/src/lib/kernel.c b/src/lib/kernel.c
index 1a9d327..79e7424 100644
--- a/src/lib/kernel.c
+++ b/src/lib/kernel.c
@@ -158,11 +158,46 @@ static const char *const s_koops_suspicious_strings[] = {
     NULL
 };
 
+static const char *const s_koops_suspicious_strings_blacklist[] = {
+    /* "BUG:" and "DEBUG:" overlaps, we don't want to recognize DEBUG messages as BUG */
+    "DEBUG:",
+
+    /* Termination */
+    NULL
+};
+
+static bool suspicious_line(const char *line)
+{
+    const char *const *str = s_koops_suspicious_strings;
+    for ( ; *str; ++str)
+        if (strstr(line, *str))
+            break;
+
+    if (!*str)
+        return false;
+
+    str = s_koops_suspicious_strings_blacklist;
+    for ( ; *str; ++str)
+        if (strstr(line, *str))
+           break;
+
+    return !*str;
+}
+
 void koops_print_suspicious_strings(void)
 {
     koops_print_suspicious_strings_filtered(NULL);
 }
 
+GList *koops_suspicious_strings_blacklist(void)
+{
+    GList *strings = NULL;
+    for (const char *const *str = s_koops_suspicious_strings_blacklist; *str; ++str)
+        strings = g_list_prepend(strings, (gpointer)*str);
+
+    return strings;
+}
+
 static bool match_any(const regex_t **res, const char *str)
 {
     for (const regex_t **r = res; *r != NULL; ++r)
@@ -312,14 +347,8 @@ next_line:
         if (oopsstart < 0)
         {
             /* Find start-of-oops markers */
-            for (const char *const *str = s_koops_suspicious_strings; *str; ++str)
-            {
-                if (strstr(curline, *str))
-                {
-                    oopsstart = i;
-                    break;
-                }
-            }
+            if (suspicious_line(curline))
+                oopsstart = i;
 
             if (oopsstart >= 0)
             {
@@ -407,18 +436,9 @@ next_line:
             /* kernel end-of-oops marker (not including marker itself) */
             else if (strstr(curline, "---[ end trace"))
                 oopsend = i-1;
-            else
-            {
-                /* if a new oops starts, this one has ended */
-                for (const char *const *str = s_koops_suspicious_strings; *str; ++str)
-                {
-                    if (strstr(curline, *str))
-                    {
-                        oopsend = i-1;
-                        break;
-                    }
-                }
-            }
+            /* if a new oops starts, this one has ended */
+            else if (suspicious_line(curline))
+                oopsend = i-1;
 
             if (oopsend <= i)
             {
-- 
1.8.3.1