From: zsugabubus <zsugabubus@national.shitposting.agency>
To: Bart Schaefer <schaefer@brasslantern.com>
Cc: Zsh hackers list <zsh-workers@zsh.org>
Subject: Re: [BUG] malloc inside signal handler
Date: Sat, 31 Jul 2021 22:25:47 +0200 [thread overview]
Message-ID: <20210731202547.yxzvwevxvy22ywm3@localhost> (raw)
In-Reply-To: <CAH+w=7YaKruWbbROqsi09KVNyv38wWgk8c+6wwk4NL4x64n=UQ@mail.gmail.com>
On Fri, Jul 30, 2021 at 06:33:08PM -0700, Bart Schaefer wrote:
> Under what circumstances are you generating this error?
I had the crash with the following command:
zsh -c ". hashes.zsh; print ~dir"
that was being executed inside $TERMINAL -e so that explains SIGWINCH.
(hashes.zsh contains a few hash -d lines.)
Unfortunately, I could not find any way to reproduce this again, even
though I call it a few hundred times a day.
However, looking at the stack trace it seems straightforward (for me)
what's going on:
shingetline() calls winch_unblock() and dont_queue_signals() so fgetc()
can be interrupted at any time.
$ gdb zsh -ex 'b input.c:153' -ex 'r' -ex 'b adjustwinsize' -ex 'signal SIGWINCH' -ex 'bt'
Just to make sure, it confirms that SIGWINCH can be handled around
fgetc(), maybe during a memory allocation inside it so if
adjustwinsize() also uses malloc() that can be fatal.
--
zsugabubus
next prev parent reply other threads:[~2021-07-31 20:26 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-07-24 22:50 zsugabubus
2021-07-31 1:33 ` Bart Schaefer
2021-07-31 20:25 ` zsugabubus [this message]
2021-08-17 4:20 ` Bart Schaefer
2021-08-17 8:21 ` Peter Stephenson
2021-08-18 19:27 ` Peter Stephenson
2021-08-26 15:46 ` Peter Stephenson
2021-08-26 15:51 ` Bart Schaefer
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