From 7417505e1d93cc95ec648b74e3c801bc67aacb9f Mon Sep 17 00:00:00 2001
From: Jakub Filak <jfilak@redhat.com>
Date: Thu, 7 May 2015 11:07:12 +0200
Subject: [ABRT PATCH] daemon, dbus: allow only root to create CCpp, Koops,
 vmcore and xorg
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Florian Weimer <fweimer@redhat.com>:
    This prevents users from feeding things that are not actually
    coredumps and excerpts from /proc to these analyzers.

    For example, it should not be possible to trigger a rule with
    “EVENT=post-create analyzer=CCpp” using NewProblem

Related: #1212861

Signed-off-by: Jakub Filak <jfilak@redhat.com>
---
 src/daemon/abrt-server.c |  2 +-
 src/dbus/abrt-dbus.c     | 10 +++++++++-
 src/include/libabrt.h    |  2 ++
 src/lib/hooklib.c        | 24 ++++++++++++++++++++++++
 4 files changed, 36 insertions(+), 2 deletions(-)

diff --git a/src/daemon/abrt-server.c b/src/daemon/abrt-server.c
index d3fa1b5..afd9fd3 100644
--- a/src/daemon/abrt-server.c
+++ b/src/daemon/abrt-server.c
@@ -487,7 +487,7 @@ static gboolean key_value_ok(gchar *key, gchar *value)
         }
     }
 
-    return TRUE;
+    return allowed_new_user_problem_entry(client_uid, key, value);
 }
 
 /* Handles a message received from client over socket. */
diff --git a/src/dbus/abrt-dbus.c b/src/dbus/abrt-dbus.c
index 6de15e9..bef95bd 100644
--- a/src/dbus/abrt-dbus.c
+++ b/src/dbus/abrt-dbus.c
@@ -168,6 +168,7 @@ bool allowed_problem_dir(const char *dir_name)
 
 static char *handle_new_problem(GVariant *problem_info, uid_t caller_uid, char **error)
 {
+    char *problem_id = NULL;
     problem_data_t *pd = problem_data_new();
 
     GVariantIter *iter;
@@ -175,6 +176,12 @@ static char *handle_new_problem(GVariant *problem_info, uid_t caller_uid, char *
     gchar *key, *value;
     while (g_variant_iter_loop(iter, "{ss}", &key, &value))
     {
+        if (allowed_new_user_problem_entry(caller_uid, key, value) == false)
+        {
+            *error = xasprintf("You are not allowed to create element '%s' containing '%s'", key, value);
+            goto finito;
+        }
+
         problem_data_add_text_editable(pd, key, value);
     }
 
@@ -189,12 +196,13 @@ static char *handle_new_problem(GVariant *problem_info, uid_t caller_uid, char *
     /* At least it should generate local problem identifier UUID */
     problem_data_add_basics(pd);
 
-    char *problem_id = problem_data_save(pd);
+    problem_id = problem_data_save(pd);
     if (problem_id)
         notify_new_path(problem_id);
     else if (error)
         *error = xasprintf("Cannot create a new problem");
 
+finito:
     problem_data_free(pd);
     return problem_id;
 }
diff --git a/src/include/libabrt.h b/src/include/libabrt.h
index 5bf2397..3749a31 100644
--- a/src/include/libabrt.h
+++ b/src/include/libabrt.h
@@ -51,6 +51,8 @@ char *get_backtrace(const char *dump_dir_name, unsigned timeout_sec, const char
 bool dir_is_in_dump_location(const char *dir_name);
 #define dir_has_correct_permissions abrt_dir_has_correct_permissions
 bool dir_has_correct_permissions(const char *dir_name);
+#define allowed_new_user_problem_entry abrt_allowed_new_user_problem_entry
+bool allowed_new_user_problem_entry(uid_t uid, const char *name, const char *value);
 
 #define g_settings_nMaxCrashReportsSize abrt_g_settings_nMaxCrashReportsSize
 extern unsigned int  g_settings_nMaxCrashReportsSize;
diff --git a/src/lib/hooklib.c b/src/lib/hooklib.c
index 4b20025..8e93663 100644
--- a/src/lib/hooklib.c
+++ b/src/lib/hooklib.c
@@ -483,3 +483,27 @@ bool dir_has_correct_permissions(const char *dir_name)
     }
     return true;
 }
+
+bool allowed_new_user_problem_entry(uid_t uid, const char *name, const char *value)
+{
+    /* Allow root to create everything */
+    if (uid == 0)
+        return true;
+
+    /* Permit non-root users to create everything except: analyzer and type */
+    if (strcmp(name, FILENAME_ANALYZER) != 0
+     && strcmp(name, FILENAME_TYPE) != 0
+     /* compatibility value used in abrt-server */
+     && strcmp(name, "basename") != 0)
+        return true;
+
+    /* Permit non-root users to create all types except: C/C++, Koops, vmcore and xorg */
+     if (strcmp(value, "CCpp") != 0
+      && strcmp(value, "Kerneloops") != 0
+      && strcmp(value, "vmcore") != 0
+      && strcmp(value, "xorg") != 0)
+        return true;
+
+    error_msg("Only root is permitted to create element '%s' containing '%s'", name, value);
+    return false;
+}
-- 
1.8.3.1

