From 4636007dd4cebca8ee10738a7833f629d8687529 Mon Sep 17 00:00:00 2001
From: Alan Coopersmith <alan.coopersmith@oracle.com>
Date: Sat, 17 Dec 2022 12:23:45 -0800
Subject: Fix CVE-2022-46285: Infinite loop on unclosed  comments

When reading XPM images from a file with libXpm 3.5.14 or older, if a
comment in the file is not closed (i.e. a C-style comment starts with
"/*" and is missing the closing "*/"), the ParseComment() function will
loop forever calling getc() to try to read the rest of the comment,
failing to notice that it has returned EOF, which may cause a denial of
service to the calling program.

Reported-by: Marco Ivaldi <raptor@0xdeadbeef.info>
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>

Origin:
https://gitlab.freedesktop.org/xorg/lib/libxpm/-/commit/a3a7c6dcc3b629d765014816c566c63165c63ca8
---
 lib/Xm/Xpmdata.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/lib/Xm/Xpmdata.c b/lib/Xm/Xpmdata.c
index d65ae57..9c53f90 100644
--- a/lib/Xm/Xpmdata.c
+++ b/lib/Xm/Xpmdata.c
@@ -171,6 +171,10 @@ ParseComment(mdata)
 		notend = 0;
 		ungetc(*s, file);
 	    }
+	    else if (c == EOF) {
+		/* hit end of file before the end of the comment */
+		return XpmFileInvalid;
+	    }
 	}
 	return 0;
     }
-- 
2.46.0

