From 5c9602bcf2792ae45a657939e718e13be38230bf Mon Sep 17 00:00:00 2001
From: Promise Charles <descencybobby@gmail.com>
Date: Thu, 4 Dec 2025 04:35:26 -0500
Subject: [PATCH] suricata: add error about missing runmode

If a runmode is missing but other params are passed on the commandline,
issue an error.

Ticket: #5711

Signed-off-by: Promise Charles <descencybobby@gmail.com>
---
 examples/lib/cplusplus/main.cpp | 2 +-
 examples/lib/custom/main.c      | 2 +-
 examples/lib/live/main.c        | 2 +-
 examples/lib/simple/main.c      | 2 +-
 src/main.c                      | 2 +-
 src/suricata.c                  | 7 ++++++-
 src/suricata.h                  | 2 +-
 7 files changed, 12 insertions(+), 7 deletions(-)

diff --git a/examples/lib/cplusplus/main.cpp b/examples/lib/cplusplus/main.cpp
index f8bead08c9..2a071a26d6 100644
--- a/examples/lib/cplusplus/main.cpp
+++ b/examples/lib/cplusplus/main.cpp
@@ -26,7 +26,7 @@ int main(int argc, char **argv)
     SCParseCommandLine(argc, argv);
 
     /* Validate/finalize the runmode. */
-    if (SCFinalizeRunMode() != TM_ECODE_OK) {
+    if (SCFinalizeRunMode(argc) != TM_ECODE_OK) {
         exit(EXIT_FAILURE);
     }
 
diff --git a/examples/lib/custom/main.c b/examples/lib/custom/main.c
index 30e99b05fc..b11b6e01d7 100644
--- a/examples/lib/custom/main.c
+++ b/examples/lib/custom/main.c
@@ -204,7 +204,7 @@ int main(int argc, char **argv)
     SCRunmodeSet(RUNMODE_LIB);
 
     /* Validate/finalize the runmode. */
-    if (SCFinalizeRunMode() != TM_ECODE_OK) {
+    if (SCFinalizeRunMode(argc) != TM_ECODE_OK) {
         exit(EXIT_FAILURE);
     }
 
diff --git a/examples/lib/live/main.c b/examples/lib/live/main.c
index ff509f40ef..572a7dde24 100644
--- a/examples/lib/live/main.c
+++ b/examples/lib/live/main.c
@@ -264,7 +264,7 @@ int main(int argc, char **argv)
     SCRunmodeSet(RUNMODE_LIB);
 
     /* Validate/finalize the runmode. */
-    if (SCFinalizeRunMode() != TM_ECODE_OK) {
+    if (SCFinalizeRunMode(suricata_argc) != TM_ECODE_OK) {
         exit(EXIT_FAILURE);
     }
 
diff --git a/examples/lib/simple/main.c b/examples/lib/simple/main.c
index f8bead08c9..2a071a26d6 100644
--- a/examples/lib/simple/main.c
+++ b/examples/lib/simple/main.c
@@ -26,7 +26,7 @@ int main(int argc, char **argv)
     SCParseCommandLine(argc, argv);
 
     /* Validate/finalize the runmode. */
-    if (SCFinalizeRunMode() != TM_ECODE_OK) {
+    if (SCFinalizeRunMode(argc) != TM_ECODE_OK) {
         exit(EXIT_FAILURE);
     }
 
diff --git a/src/main.c b/src/main.c
index 86367c1ef1..77270d7a02 100644
--- a/src/main.c
+++ b/src/main.c
@@ -33,7 +33,7 @@ int main(int argc, char **argv)
         exit(EXIT_FAILURE);
     }
 
-    if (SCFinalizeRunMode() != TM_ECODE_OK) {
+    if (SCFinalizeRunMode(argc) != TM_ECODE_OK) {
         exit(EXIT_FAILURE);
     }
 
diff --git a/src/suricata.c b/src/suricata.c
index 217c9f1382..78b3b34ed0 100644
--- a/src/suricata.c
+++ b/src/suricata.c
@@ -2518,11 +2518,16 @@ int SCStartInternalRunMode(int argc, char **argv)
     return TM_ECODE_OK;
 }
 
-int SCFinalizeRunMode(void)
+int SCFinalizeRunMode(int argc)
 {
     SCInstance *suri = &suricata;
     switch (suri->run_mode) {
         case RUNMODE_UNKNOWN:
+            /* Only warn if user passed arguments */
+            if (argc > 1) {
+                SCLogError("Please specify a runmode or capture option. "
+                           "Use --list-runmodes to see available runmodes.");
+            }
             PrintUsage(suri->progname);
             return TM_ECODE_FAILED;
         default:
diff --git a/src/suricata.h b/src/suricata.h
index 8264851588..a32bf98b74 100644
--- a/src/suricata.h
+++ b/src/suricata.h
@@ -234,7 +234,7 @@ int InitGlobal(void);
 void GlobalsDestroy(void);
 int PostConfLoadedSetup(SCInstance *suri);
 void PostConfLoadedDetectSetup(SCInstance *suri);
-int SCFinalizeRunMode(void);
+int SCFinalizeRunMode(int argc);
 TmEcode SCParseCommandLine(int argc, char **argv);
 int SCStartInternalRunMode(int argc, char **argv);
 TmEcode SCLoadYamlConfig(void);