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From 54e3d1414e1a031d6f635f8fcbe273eecfd65560 Mon Sep 17 00:00:00 2001
From: Karel Zak <kzak@redhat.com>
Date: Tue, 5 Feb 2019 12:06:00 +0100
Subject: [PATCH 39/40] col: make flush_line() a little bit robust

The code is horrible. The core of the problem are signed integers
and no check for the limits.

This patch fixes c->c_column = cur_col; where c_column is "short"
and "cur_col" is int. Let's use "int" for all the variables. It's
really not perfect as for bigger lines it can segfault again...

The patch also removes some unnecessary static variables.

Upstream: http://github.com/karelzak/util-linux/commit/004356f05018e3bfcaddd2652846659a4d8481f3
Addresses: https://bugzilla.redhat.com/show_bug.cgi?id=1803753
Addresses: https://github.com/karelzak/util-linux/issues/749
Signed-off-by: Karel Zak <kzak@redhat.com>
---
 text-utils/col.c | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/text-utils/col.c b/text-utils/col.c
index 3d9e15d26..c2f8db64d 100644
--- a/text-utils/col.c
+++ b/text-utils/col.c
@@ -88,7 +88,7 @@ typedef char CSET;
 typedef struct char_str {
 #define	CS_NORMAL	1
 #define	CS_ALTERNATE	2
-	short		c_column;	/* column character is in */
+	int		c_column;	/* column character is in */
 	CSET		c_set;		/* character set (currently only 2) */
 	wchar_t		c_char;		/* character in question */
 	int		c_width;	/* character width */
@@ -476,8 +476,9 @@ void flush_line(LINE *l)
 	nchars = l->l_line_len;
 
 	if (l->l_needs_sort) {
-		static CHAR *sorted;
-		static int count_size, *count, i, save, sorted_size, tot;
+		static CHAR *sorted = NULL;
+		static int count_size = 0, *count = NULL, sorted_size = 0;
+		int i, tot;
 
 		/*
 		 * Do an O(n) sort on l->l_line by column being careful to
@@ -494,7 +495,7 @@ void flush_line(LINE *l)
 			    (unsigned)sizeof(int) * count_size);
 		}
 		memset(count, 0, sizeof(int) * l->l_max_col + 1);
-		for (i = nchars, c = l->l_line; --i >= 0; c++)
+		for (i = nchars, c = l->l_line; c && --i >= 0; c++)
 			count[c->c_column]++;
 
 		/*
@@ -502,7 +503,7 @@ void flush_line(LINE *l)
 		 * indices into new line.
 		 */
 		for (tot = 0, i = 0; i <= l->l_max_col; i++) {
-			save = count[i];
+			int save = count[i];
 			count[i] = tot;
 			tot += save;
 		}
-- 
2.25.4