bug#56369: 29.0.50; abort-redisplay: Crash after 'recenter'

[Florian Rommel]

Tags: patch

I get a crash caused by a failed free() [see attached backtrace] when
running vterm [1] which calls 'recenter' from a loaded module.
With gdb, in 'safe_free' I see that the address of the to-be-freed
arguments array (allocated in 'module_funcall') is off by one word.

I don't know the details of the specpdl stack but I assume that there
is a missing 'ubind_to' in 'recenter' before an early return.  When I
add it (see the attached patch) the problem is gone.

[1] https://github.com/akermu/emacs-libvterm

backtrace.txt
Description: Text document

0001-abort-redisplay-Add-missing-unbind_to-in-recenter.patch
Description: Text Data