added AFL_IGNORE_UNKNOWN_ENVS

docs/Changelog.md

@@ -61,7 +61,8 @@ sending a mail to <afl-users+subscribe@googlegroups.com>.
     - Added a new example harness to compare python, c, and rust bindings
   - afl-cmin and afl-showmap now support the -f option
   - changed default: no memory limit for afl-cmin and afl-cmin.bash
-  - warn on any _AFL and __AFL env vars
+  - warn on any _AFL and __AFL env vars.
+  - set AFL_IGNORE_UNKNOWN_ENVS to not warn on unknown AFL_... env vars.
   - added dummy Makefile to instrumentation/
   - Updated utils/afl_frida to be 5% faster, 7% on x86_x64
   - Added AFL_KILL_SIGNAL env variable (thanks @v-p-b)

docs/env_variables.md

@@ -5,6 +5,10 @@
   users or for some types of custom fuzzing setups. See [README.md](README.md) for the general
   instruction manual.
 
+  Note that most tools will warn on any unknown AFL environment variables.
+  This is for warning on typos that can happen. If you want to disable this
+  check then set the `AFL_IGNORE_UNKNOWN_ENVS` environment variable.
+
 ## 1) Settings for all compilers
 
 Starting with afl++ 3.0 there is only one compiler: afl-cc
@@ -18,7 +22,6 @@ To select the different instrumentation modes this can be done by
 `MODE` can be one of `LTO` (afl-clang-lto*), `LLVM` (afl-clang-fast*), `GCC_PLUGIN`
 (afl-g*-fast) or `GCC` (afl-gcc/afl-g++).
 
-
 Because (with the exception of the --afl-MODE command line option) the
 compile-time tools do not accept afl specific command-line options, they
 make fairly broad use of environmental variables instead: