** Description changed:

+ [ Impact ]
+ 
+  * Escape sequences or tab characters at agetty's login prompt are handled 
incorrectly.
+  On Noble:
+    - Escape sequences are not escaped at all. Using the arrow keys can move 
around the login prompt and erase any text on screen.
+    - Using the arrow keys at all causes the subsequent login attempt to hang 
before the flow restarts regardless of the correctness of provided credentials.
+  On Questing:
+    - Escape sequences are escaped correctly but leave extra characters that 
are impossible to erase from the login prompt.
+    - The login flow is unaffected by any leftover characters at the prompt.
+ 
+  The bug is not present if an unsuccessful login attempt is made first,
+ as further login prompts are actually served by login instead of agetty.
+ 
+ [ Test Plan ]
+ 
+  * At the agetty login prompt, press escape sequences including arrow keys, 
tab, and escape.
+  * Verify that the escape sequences only cause strings to be printed at the 
prompt without performing any other action.
+  * Verify that the printed strings (and only the printed strings) can be 
erased in their entirety.
+  * Verify that the login flow otherwise works as expected.
+ 
+ [ Where problems could occur ]
+ 
+  * The changes for this fix are limited to how escape sequences are
+ printed at the agetty login prompt but normal logins should be verified
+ regardless.
+ 
+ [ Other Info ]
+ 
+  * Link to upstream issue: 
https://github.com/util-linux/util-linux/issues/3624
+  * Link to upstream fix: 
https://github.com/util-linux/util-linux/commit/b462fdefe74836c22cb02039dca419a512dc6c88
+ 
+ [ Original Description ]
+ 
  On Ubuntu Server 24.04.2 LTS, using the arrow key and backspace at the
  `tty1` login prompt breaks the prompt, preventing login.
  
  ## Steps to reproduce:
  1. Boot into Ubuntu Server (no GUI).
  2. Wait for the `tty1` login prompt.
  3. Press an arrow key (← or →).
  4. Press backspace to delete part of the line.
  5. Attempt to type a username and press Enter.
  
  ## Result:
  - The login prompt no longer accepts input or proceeds.
  - You cannot log in until the system is restarted.
  
  ## Expected behavior:
  - Arrow key and backspace input should be handled cleanly.
  - Login should still be possible.
  
  ## Notes:
  - This bug occurs on the text-based terminal (`tty1`) launched by 
`[email protected]`, managed by systemd.
  - Kernel version: 6.8.0-60-generic
  - Affected version: Ubuntu Server 24.04.2 LTS

** Summary changed:

- TTY1 login prompt becomes unresponsive after arrow key and backspace input
+ [SRU] TTY1 login prompt becomes unresponsive after arrow key and backspace 
input

** Merge proposal linked:
   
https://code.launchpad.net/~uralt/ubuntu/+source/util-linux/+git/util-linux/+merge/501016

** Merge proposal linked:
   
https://code.launchpad.net/~uralt/ubuntu/+source/util-linux/+git/util-linux/+merge/501017

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https://bugs.launchpad.net/bugs/2111126

Title:
  [SRU] TTY1 login prompt becomes unresponsive after arrow key and
  backspace input

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