diff --git a/Documentation/gitattributes.txt b/Documentation/gitattributes.txt
index b762bba759c790eb27c5adc0f622a954c76ecb3a..aaa073efc80522a649f17d60127aae8cc85b0b3b 100644
--- a/Documentation/gitattributes.txt
+++ b/Documentation/gitattributes.txt
@@ -297,7 +297,8 @@ for paths.
 
 Then, you would define a "diff.tex.xfuncname" configuration to
 specify a regular expression that matches a line that you would
-want to appear as the hunk header "TEXT", like this:
+want to appear as the hunk header "TEXT". Add a section to your
+`$GIT_DIR/config` file (or `$HOME/.gitconfig` file) like this:
 
 ------------------------
 [diff "tex"]
@@ -345,7 +346,8 @@ split words in a line, by specifying an appropriate regular expression
 in the "diff.*.wordRegex" configuration variable.  For example, in TeX
 a backslash followed by a sequence of letters forms a command, but
 several such commands can be run together without intervening
-whitespace.  To separate them, use a regular expression such as
+whitespace.  To separate them, use a regular expression in your
+`$GIT_DIR/config` file (or `$HOME/.gitconfig` file) like this:
 
 ------------------------
 [diff "tex"]
@@ -373,7 +375,8 @@ resulting text on stdout.
 
 For example, to show the diff of the exif information of a
 file instead of the binary information (assuming you have the
-exif tool installed):
+exif tool installed), add the following section to your
+`$GIT_DIR/config` file (or `$HOME/.gitconfig` file):
 
 ------------------------
 [diff "jpg"]
diff --git a/config.c b/config.c
index b76fe4c6dcc966f8c7c15da44d15f7cf45740f5b..2d70398b1608fa39e665fd25fbd95221b0a62d99 100644
--- a/config.c
+++ b/config.c
@@ -51,7 +51,7 @@ static char *parse_value(void)
 
 	for (;;) {
 		int c = get_next_char();
-		if (len >= sizeof(value))
+		if (len >= sizeof(value) - 1)
 			return NULL;
 		if (c == '\n') {
 			if (quote)
diff --git a/t/t1303-wacky-config.sh b/t/t1303-wacky-config.sh
index 1983076c753ea12a4f69d2a98eda3c1621daed59..080117c6bcbb61078539f36011ecd62780bae305 100755
--- a/t/t1303-wacky-config.sh
+++ b/t/t1303-wacky-config.sh
@@ -10,7 +10,7 @@ setup() {
 
 check() {
 	echo "$2" >expected
-	git config --get "$1" >actual
+	git config --get "$1" >actual 2>&1
 	test_cmp actual expected
 }
 
@@ -40,4 +40,11 @@ test_expect_success 'make sure git config escapes section names properly' '
 	check "$SECTION" bar
 '
 
+LONG_VALUE=$(printf "x%01021dx a" 7)
+test_expect_success 'do not crash on special long config line' '
+	setup &&
+	git config section.key "$LONG_VALUE" &&
+	check section.key "fatal: bad config file line 2 in .git/config"
+'
+
 test_done