Thank you for filling out a Git bug report!
Please answer the following questions to help us understand your issue.

What did you do before the bug happened? (Steps to reproduce your issue)
I tried to create a patch file of a commit in another directory using the following command:
[josi@localhost typescript]$ git format-patch -1 236a9 --output=/home/josi/tmp/patches/txt-6117.patch

What did you expect to happen? (Expected behavior)
I expected a patch file at the location specified in --output

What happened instead? (Actual behavior)
git crashed:
0001-Txture-Core-Implemented-whitelisting-for-groovy-scri.patch
free(): invalid pointer
Aborted (core dumped)

What's different between what you expected and what actually happened?
I didn't expect the crash :D

Anything else you want to add:
I do have a full core dump recorded by ABRT (Fedora). Please let me know at johannes.postler@txture.io if you need thaThe following is the backtrace according to ABRT:
{   "signal": 6
,   "executable": "/usr/bin/git"
,   "stacktrace":
      [ {   "crash_thread": true
        ,   "frames":
              [ {   "address": 139721002875845
                ,   "build_id": "2602cd2de6dc672a5ec4378ace0b4a68ea5b13ea"
                ,   "build_id_offset": 252869
                ,   "function_name": "raise"
                ,   "file_name": "/lib64/libc.so.6"
                }
              , {   "address": 139721002780836
                ,   "build_id": "2602cd2de6dc672a5ec4378ace0b4a68ea5b13ea"
                ,   "build_id_offset": 157860
                ,   "function_name": "abort"
                ,   "file_name": "/lib64/libc.so.6"
                }
              , {   "address": 139721003147559
                ,   "build_id": "2602cd2de6dc672a5ec4378ace0b4a68ea5b13ea"
                ,   "build_id_offset": 524583
                ,   "function_name": "__libc_message"
                ,   "file_name": "/lib64/libc.so.6"
                }
              , {   "address": 139721003179548
                ,   "build_id": "2602cd2de6dc672a5ec4378ace0b4a68ea5b13ea"
                ,   "build_id_offset": 556572
                ,   "function_name": ".annobin_top_check.start"
                ,   "file_name": "/lib64/libc.so.6"
                }
              , {   "address": 139721003186412
                ,   "build_id": "2602cd2de6dc672a5ec4378ace0b4a68ea5b13ea"
                ,   "build_id_offset": 563436
                ,   "function_name": "_int_free"
                ,   "file_name": "/lib64/libc.so.6"
                }
              , {   "address": 139721003104931
                ,   "build_id": "2602cd2de6dc672a5ec4378ace0b4a68ea5b13ea"
                ,   "build_id_offset": 481955
                ,   "function_name": "fclose@@GLIBC_2.2.5"
                ,   "file_name": "/lib64/libc.so.6"
                }
              , {   "address": 94420595460270
                ,   "build_id": "ba2b8ad417de884d751cd7503b17e9ce357b2dcf"
                ,   "build_id_offset": 538798
                ,   "function_name": "cmd_format_patch"
                ,   "file_name": "/usr/bin/git"
                }
              , {   "address": 94420595060875
                ,   "build_id": "ba2b8ad417de884d751cd7503b17e9ce357b2dcf"
                ,   "build_id_offset": 139403
                ,   "function_name": "handle_builtin.lto_priv.0"
                ,   "file_name": "/usr/bin/git"
                }
              , {   "address": 94420595041051
                ,   "build_id": "ba2b8ad417de884d751cd7503b17e9ce357b2dcf"
                ,   "build_id_offset": 119579
                ,   "function_name": "main"
                ,   "file_name": "/usr/bin/git"
                } ]
        } ]
}

Please review the rest of the bug report below.
You can delete any lines you don't wish to share.


[System Info]
git version:
git version 2.28.0
cpu: x86_64
no commit associated with this build
sizeof-long: 8
sizeof-size_t: 8
shell-path: /bin/sh
uname: Linux 5.8.16-300.fc33.x86_64 #1 SMP Mon Oct 19 13:18:33 UTC 2020 x86_64
compiler info: gnuc: 10.2
libc info: glibc: 2.32
$SHELL (typically, interactive shell): /bin/bash


[Enabled Hooks]
applypatch-msg
pre-applypatch
post-applypatch
pre-commit
pre-merge-commit
prepare-commit-msg
commit-msg
post-commit
pre-rebase
post-checkout
post-merge
pre-push
pre-receive
update
post-receive
post-update
push-to-checkout
pre-auto-gc
post-rewrite
sendemail-validate