From 846189b62c9640c29049c51e56d502131af7f165 Mon Sep 17 00:00:00 2001
From: Philippe Teuwen <yobibe@gmail.com>
Date: Sun, 22 Sep 2013 19:32:37 +0200
Subject: [PATCH] Check data from getenv("LIBNFC_LOG_LEVEL") and config file

Problem reported by Coverity:
CID 1090344 (#1 of 1): Use of untrusted string value (TAINTED_STRING)
. tainted_string: Passing tainted string "res->log_level" to "log_init(nfc_context const *)", which cannot accept tainted data.[show details]
---
 libnfc/conf.c         | 5 ++++-
 libnfc/log.c          | 5 ++++-
 libnfc/nfc-internal.c | 5 ++++-
 3 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/libnfc/conf.c b/libnfc/conf.c
index 7bda47d..307467f 100644
--- a/libnfc/conf.c
+++ b/libnfc/conf.c
@@ -125,7 +125,10 @@ conf_keyvalue_context(void *data, const char *key, const char *value)
   } else if (strcmp(key, "allow_intrusive_scan") == 0) {
     string_as_boolean(value, &(context->allow_intrusive_scan));
   } else if (strcmp(key, "log_level") == 0) {
-    context->log_level = atoi(value);
+    int i = atoi(value);
+    if (i < 0) i = 0;
+    if (i > 3) i = 3;
+    context->log_level = i;
   } else if (strcmp(key, "device.name") == 0) {
     if ((context->user_defined_device_count == 0) || strcmp(context->user_defined_devices[context->user_defined_device_count - 1].name, "") != 0) {
       if (context->user_defined_device_count >= MAX_USER_DEFINED_DEVICES) {
diff --git a/libnfc/log.c b/libnfc/log.c
index 0144167..83615b3 100644
--- a/libnfc/log.c
+++ b/libnfc/log.c
@@ -87,7 +87,10 @@ log_put(const uint8_t group, const char *category, const uint8_t priority, const
     log_level = 1;
 #endif
   } else {
-    log_level = atoi(env_log_level);
+    int i = atoi(env_log_level);
+    if (i < 0) i = 0;
+    if (i > 3) i = 3;
+    log_level = i;
   }
 
   //  printf("log_level = %"PRIu32" group = %"PRIu8" priority = %"PRIu8"\n", log_level, group, priority);
diff --git a/libnfc/nfc-internal.c b/libnfc/nfc-internal.c
index 031483e..37512b4 100644
--- a/libnfc/nfc-internal.c
+++ b/libnfc/nfc-internal.c
@@ -121,7 +121,10 @@ nfc_context_new(void)
   // log level
   envvar = getenv("LIBNFC_LOG_LEVEL");
   if (envvar) {
-    res->log_level = atoi(envvar);
+    int i = atoi(envvar);
+    if (i < 0) i = 0;
+    if (i > 3) i = 3;
+    res->log_level = i;
   }
 #endif // ENVVARS