session: Handle invalid strings in keyboard prompt

alexcrichton · Nov 5, 2024 · 1868c37 · 1868c37
1 parent 38f989c
commit 1868c37
Showing 1 changed file with 15 additions and 6 deletions.
diff --git a/src/session.rs b/src/session.rs
@@ -392,14 +392,23 @@ impl Session {
 
                 let prompter = unsafe { &mut **(abstrakt as *mut *mut P) };
 
-                let username =
-                    unsafe { slice::from_raw_parts(username as *const u8, username_len as usize) };
-                let username = String::from_utf8_lossy(username);
+                let username = if !username.is_null() && username_len >= 0 {
+                    let username = unsafe {
+                        slice::from_raw_parts(username as *const u8, username_len as usize)
+                    };
+                    String::from_utf8_lossy(username)
+                } else {
+                    Cow::Borrowed("")
+                };
 
-                let instruction = unsafe {
-                    slice::from_raw_parts(instruction as *const u8, instruction_len as usize)
+                let instruction = if !instruction.is_null() && instruction_len >= 0 {
+                    let instruction = unsafe {
+                        slice::from_raw_parts(instruction as *const u8, instruction_len as usize)
+                    };
+                    String::from_utf8_lossy(instruction)
+                } else {
+                    Cow::Borrowed("")
                 };
-                let instruction = String::from_utf8_lossy(instruction);
 
                 let prompts = unsafe { slice::from_raw_parts(prompts, num_prompts as usize) };
                 let responses =