Fix out-of-bounds read in c_substitute():

http://seclists.org/oss-sec/2016/q4/612

Patch copied from upstream source repository:

https://github.com/tcsh-org/tcsh/commit/6a542dc4fb2ba26518a47e9b3a9bcd6a91b94596

From 6a542dc4fb2ba26518a47e9b3a9bcd6a91b94596 Mon Sep 17 00:00:00 2001
From: christos <christos>
Date: Fri, 2 Dec 2016 16:59:28 +0000
Subject: [PATCH] Fix out of bounds read (Brooks Davis) (reproduce by starting
 tcsh and hitting tab at the prompt)

---
 ed.chared.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/ed.chared.c b/ed.chared.c
index 1277e53..310393e 100644
--- ed.chared.c
+++ ed.chared.c
@@ -750,7 +750,7 @@ c_substitute(void)
     /*
      * If we found a history character, go expand it.
      */
-    if (HIST != '\0' && *p == HIST)
+    if (p >= InputBuf && HIST != '\0' && *p == HIST)
 	nr_exp = c_excl(p);
     else
         nr_exp = 0;
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<tr><td><span title='2022-06-24 10:21:06 +0200'>2022-06-24</span></td><td><a href='/guix/commit/gnu/build/bootloader.scm?id=62c86c8391ceb8953ca972498fd75ea9298b85ff'>image: Add support for 32bit UEFI.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/bootloader/grub.scm (grub-efi32-bootloader): New variable.
(install-grub-efi32): New variable.
* gnu/build/bootloader.scm (install-efi): Add a 'targets' keyword
argument.
(install-efi-loader): Likewise.
* gnu/build/image.scm (initialize-efi32-partition): New procedure.
* gnu/packages/bootloaders.scm (grub-efi32): New variable.
* gnu/system/image.scm (esp32-partition): New variable
(efi32-disk-image): New variable.
(efi32-raw-image-type): New variable.
(system-disk-image)[partition-image]: Set '#:grub-efi32' when
calling the partition initializer.

Signed-off-by: Mathieu Othacehe &lt;othacehe@gnu.org&gt;
</span></span></td><td>Denis 'GNUtoo' Carikli</td></tr>