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

[GNU bug Tracking System]

Your message dated Sun, 03 Jul 2022 19:11:09 +0300
with message-id <83czem9nxe.fsf@gnu.org>
and subject line Re: bug#56369: 29.0.50; abort-redisplay: Crash after 'recenter'
has caused the debbugs.gnu.org bug report #56369,
regarding 29.0.50; abort-redisplay: Crash after 'recenter'
to be marked as done.

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56369: https://debbugs.gnu.org/cgi/bugreport.cgi?bug=56369
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--- Begin Message --- Subject: 29.0.50; abort-redisplay: Crash after 'recenter' Date: Sun, 03 Jul 2022 17:55:50 +0200 User-agent: Evolution 3.44.2

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

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> Subject: 
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> Re: bug#56369: 29.0.50; abort-redisplay: Crash after 'recenter'
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> Date: 
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> Sun, 03 Jul 2022 19:11:09 +0300
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> Closing.
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