Fix NameError in submit_flag and Kernel.enable_uart (#2798)

* Fix NameError in submit_flag and Kernel.enable_uart

* Add changelog entry for #2798

CHANGELOG.md

@@ -75,6 +75,7 @@ The table below shows which release corresponds to each branch, and what date th
 
 ## 5.0.0 (`dev`)
 
+- [#2798][2798] fix(flag, adb): NameError in `submit_flag` with a flag file and in `Kernel.enable_uart`
 - [#2780][2780] fix(encoders): handle unavailable xor encodings and fallback
 - [#2789][2789] feat(errno): support `-c/--context` to look up errno values for other architectures
 - [#2784][2784] docs: put plain doctest blocks in the default group for Sphinx 9
@@ -239,6 +240,7 @@ The table below shows which release corresponds to each branch, and what date th
 [2761]: https://github.com/Gallopsled/pwntools/pull/2761
 [2727]: https://github.com/Gallopsled/pwntools/pull/2727
 [2792]: https://github.com/Gallopsled/pwntools/pull/2792
+[2798]: https://github.com/Gallopsled/pwntools/pull/2798
 
 ## 4.15.1
 

pwnlib/adb/adb.py

@@ -1192,7 +1192,7 @@ class Kernel:
             'Nexus 7': 'oem uart-on',
         }
 
-        with log.waitfor('Enabling kernel UART'):
+        with log.waitfor('Enabling kernel UART') as w:
 
             if model not in known_commands:
                 log.error("Device UART is unsupported.")

pwnlib/flag/flag.py

@@ -5,6 +5,7 @@ import os
 from pwnlib.args import args
 from pwnlib.log import getLogger
 from pwnlib.tubes.remote import remote
+from pwnlib.util.misc import write
 
 env_server  = args.get('FLAG_HOST', 'flag-submission-server').strip()
 env_port    = args.get('FLAG_PORT', '31337').strip()