log: wrap rotation and write in lock

The application log is subject to rotation, so the check for
rotation, the actual rotation and write needs to be done under
lock to ensure the file pointer is in a consisten state
at the time of write().

Fixes issue:
https://redmine.openinfosecfoundation.org/issues/2155

diff --git a/src/util-debug.c b/src/util-debug.c
index 97b1626b2bb6d0ea1686b83dc3b2e63dd35b5cc0..d4ddc14a2dafd9a8d1a7054fa1bd841ff6afeec6 100644 (file)
--- a/src/util-debug.c
+++ b/src/util-debug.c
@@ -577,11 +577,13 @@ SCError SCLogMessage(const SCLogLevel log_level, const char *file,
                                           log_level, file, line, function,
                                           error_code, message) == 0)
                 {
+                    SCMutexLock(&op_iface_ctx->fp_mutex);
                     if (op_iface_ctx->rotation_flag) {
                         SCLogReopen(op_iface_ctx);
                         op_iface_ctx->rotation_flag = 0;
                     }
                     SCLogPrintToStream(op_iface_ctx->file_d, buffer);
+                    SCMutexUnlock(&op_iface_ctx->fp_mutex);
                 }
                 break;
             case SC_LOG_OP_IFACE_SYSLOG:
@@ -714,6 +716,7 @@ static inline SCLogOPIfaceCtx *SCLogInitFileOPIface(const char *file,
         goto error;
     }
 
+    SCMutexInit(&iface_ctx->fp_mutex, NULL);
     OutputRegisterFileRotationFlag(&iface_ctx->rotation_flag);
 
     iface_ctx->log_level = log_level;

diff --git a/src/util-debug.h b/src/util-debug.h
index 5148fe19f60a4ccc658b502b3991c074709c09b3..8cf49beda39cfa17ab3d43c20aa732d7e109295e 100644 (file)
--- a/src/util-debug.h
+++ b/src/util-debug.h
@@ -139,6 +139,9 @@ typedef struct SCLogOPIfaceCtx_ {
     /* override for the global_log_format(currently not used) */
     const char *log_format;
 
+    /* Mutex used for locking around rotate/write to a file. */
+    SCMutex fp_mutex;
+
     struct SCLogOPIfaceCtx_ *next;
 } SCLogOPIfaceCtx;