in_winevtlog: Handle capped values

Signed-off-by: Hiroshi Hatake <hiroshi@chronosphere.io>

Author: cosmo0920

plugins/in_winevtlog/in_winevtlog.c

@@ -200,15 +200,21 @@ static int in_winevtlog_init(struct flb_input_instance *in,
     ctx->backoff.multiplier_x1000 = (DWORD)(mult * 1000.0);
 
     /* normalize base/max/jitter/retries to sane ranges */
-    if (ctx->backoff.base_ms == 0) {
+    if (ctx->backoff.base_ms <= 0) {
         ctx->backoff.base_ms = 500;
     }
-    if (ctx->backoff.max_ms  == 0) {
+    if (ctx->backoff.max_ms  <= 0) {
         ctx->backoff.max_ms  = 30000;
     }
+    if (ctx->backoff.jitter_pct < 0) {
+        ctx->backoff.jitter_pct = 0;
+    }
     if (ctx->backoff.jitter_pct == 0) {
         ctx->backoff.jitter_pct = 20;
     }
+    if (ctx->backoff.max_retries < 0) {
+        ctx->backoff.max_retries = 0;
+    }
     if (ctx->backoff.max_retries == 0) {
         ctx->backoff.max_retries = 8;
     }
@@ -223,6 +229,9 @@ static int in_winevtlog_init(struct flb_input_instance *in,
     if (ctx->backoff.jitter_pct > 100U) {  /* jitter as percentage */
         ctx->backoff.jitter_pct = 100U;
     }
+    if ((unsigned) ctx->backoff.max_retries > 100U) { /* cap retries */
+        ctx->backoff.max_retries = 100;
+    }
     /* ensure ordering */
     if (ctx->backoff.max_ms < ctx->backoff.base_ms) {
         flb_plg_warn(in, "reconnect.max_ms < reconnect.base_ms, swapping values");