From: Philipp Stephani <phst@google.com>
Date: Sat, 11 Dec 2021 12:51:34 +0000 (+0100)
Subject: Avoid undefined behavior in 'send-process-region' (Bug#52369).
X-Git-Tag: emacs-28.0.91~55
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=8a0734329a4faf0b45627763af74222bdd0ec143;p=emacs.git

Avoid undefined behavior in 'send-process-region' (Bug#52369).

* src/process.c (send_process): Signal an error if the file descriptor
has already been closed.
---

diff --git a/src/process.c b/src/process.c
index 75ba191fa10..1d307d5242c 100644
--- a/src/process.c
+++ b/src/process.c
@@ -6520,6 +6520,9 @@ send_process (Lisp_Object proc, const char *buf, ptrdiff_t len,
 	  /* Send this batch, using one or more write calls.  */
 	  ptrdiff_t written = 0;
 	  int outfd = p->outfd;
+          if (outfd < 0)
+            error ("Output file descriptor of %s is closed",
+                   SDATA (p->name));
 	  eassert (0 <= outfd && outfd < FD_SETSIZE);
 #ifdef DATAGRAM_SOCKETS
 	  if (DATAGRAM_CHAN_P (outfd))