From 6c204270db815d639582c3be16f7797017dcde81 Mon Sep 17 00:00:00 2001
From: Philippe Antoine <pantoine@oisf.net>
Date: Thu, 23 Jul 2026 16:07:06 +0200
Subject: [PATCH] rfb: keep failure_reason as Vec<u8>

And log it with from_utf8_lossy

Since we may now cut a too big failure_reason breaking a valid
utf-8 string

Ticket: 8731
(cherry picked from commit c608165c043ba9a4f96a2679d5bae5de1ef1d6cb)
---
 rust/src/rfb/logger.rs | 5 ++++-
 rust/src/rfb/parser.rs | 6 +++---
 2 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/rust/src/rfb/logger.rs b/rust/src/rfb/logger.rs
index 9934aae057..d677bef694 100644
--- a/rust/src/rfb/logger.rs
+++ b/rust/src/rfb/logger.rs
@@ -81,7 +81,10 @@ fn log_rfb(tx: &RFBTransaction, js: &mut JsonBuilder) -> Result<(), JsonError> {
     js.close()?; // Close authentication.
 
     if let Some(ref reason) = tx.tc_failure_reason {
-        js.set_string("server_security_failure_reason", &reason.reason_string)?;
+        js.set_string(
+            "server_security_failure_reason",
+            &String::from_utf8_lossy(&reason.reason_string),
+        )?;
     }
 
     // Client/Server init
diff --git a/rust/src/rfb/parser.rs b/rust/src/rfb/parser.rs
index 210571fd1b..2f8cbb52dd 100644
--- a/rust/src/rfb/parser.rs
+++ b/rust/src/rfb/parser.rs
@@ -93,7 +93,7 @@ pub struct SecurityResult {
 }
 
 pub struct FailureReason {
-    pub reason_string: String,
+    pub reason_string: Vec<u8>,
     pub to_skip: u32,
 }
 
@@ -182,11 +182,11 @@ pub fn parse_security_result(i: &[u8]) -> IResult<&[u8], SecurityResult> {
 pub fn parse_failure_reason(i: &[u8], max_len: u32) -> IResult<&[u8], FailureReason> {
     let (i, reason_length) = be_u32(i)?;
     let to_skip = reason_length.saturating_sub(max_len);
-    let (i, reason_string) = map_res(take((reason_length - to_skip) as usize), str::from_utf8)(i)?;
+    let (i, reason_string) = take((reason_length - to_skip) as usize)(i)?;
     Ok((
         i,
         FailureReason {
-            reason_string: reason_string.to_string(),
+            reason_string: reason_string.to_vec(),
             to_skip,
         },
     ))