GNU bug report logs - #24118
25.1; [PATCH] Fix a possible crash caused by mapcar1

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Package: emacs;

Reported by: Chris Feng <chris.w.feng <at> gmail.com>

Date: Sun, 31 Jul 2016 12:48:01 UTC

Severity: normal

Tags: patch

Found in version 25.1

Done: Paul Eggert <eggert <at> cs.ucla.edu>

Bug is archived. No further changes may be made.

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From: Andreas Schwab <schwab <at> linux-m68k.org>
To: Chris Feng <chris.w.feng <at> gmail.com>
Cc: 24118 <at> debbugs.gnu.org
Subject: bug#24118: 25.1; [PATCH] Fix a possible crash caused by mapcar1
Date: Sun, 31 Jul 2016 15:18:09 +0200

Chris Feng <chris.w.feng <at> gmail.com> writes:

> diff --git a/src/fns.c b/src/fns.c
> index d5a1f74..1804bce 100644
> --- a/src/fns.c
> +++ b/src/fns.c
> @@ -2524,6 +2524,10 @@ mapcar1 (EMACS_INT leni, Lisp_Object *vals, Lisp_Object fn, Lisp_Object seq)
>  	    vals[i] = dummy;
>  	  tail = XCDR (tail);
>  	}
> +
> +      /* In case the list was tampered and the loop terminated early. */
> +      if (i < leni)
> +        memclear (vals + i, (leni - i) * word_size);

That should not depend on the representation of Qnil.

Andreas.

-- 
Andreas Schwab, schwab <at> linux-m68k.org
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This bug report was last modified 8 years and 290 days ago.

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