Index: head/contrib/netbsd-tests/usr.bin/grep/t_grep.sh
===================================================================
--- head/contrib/netbsd-tests/usr.bin/grep/t_grep.sh
+++ head/contrib/netbsd-tests/usr.bin/grep/t_grep.sh
@@ -430,7 +430,7 @@
 	done
 
 	atf_check -s exit:0 -x '[ $(grep -o x test.in | wc -l) -eq 4096 ]'
-	#atf_check -s exit:1 -x 'grep -on x test.in | grep -v "1:x"'
+	atf_check -s exit:1 -x 'grep -on x test.in | grep -v "1:x"'
 }
 
 atf_test_case fgrep_sanity
@@ -510,6 +510,39 @@
 	atf_check -s exit:1 grep -v -w "x" test2
 }
 
+atf_test_case ocolor_metadata
+ocolor_metadata_head()
+{
+	atf_set "descr" "Check for -n/-b producing per-line metadata output"
+}
+ocolor_metadata_body()
+{
+	grep_type
+	if [ $? -eq $GREP_TYPE_GNU_FREEBSD ]; then
+		atf_expect_fail "this test does not pass with GNU grep in base"
+	fi
+
+	printf "xxx\nyyyy\nzzz\nfoobarbaz\n" > test1
+	check_expr="^[^:]*[0-9][^:]*:[^:]+$"
+
+	atf_check -o inline:"1:1:xx\n" grep -bon "xx$" test1
+
+	atf_check -o inline:"2:4:yyyy\n" grep -bn "yy" test1
+
+	atf_check -o inline:"2:6:yy\n" grep -bon "yy$" test1
+
+	# These checks ensure that grep isn't producing bogus line numbering
+	# in the middle of a line.
+	atf_check -s exit:1 -x \
+	    "grep -Eon 'x|y|z|f' test1 | grep -Ev '${check_expr}'"
+
+	atf_check -s exit:1 -x \
+	    "grep -En 'x|y|z|f' --color=always test1 | grep -Ev '${check_expr}'"
+
+	atf_check -s exit:1 -x \
+	    "grep -Eon 'x|y|z|f' --color=always test1 | grep -Ev '${check_expr}'"
+}
+
 atf_test_case grep_nomatch_flags
 grep_nomatch_flags_head()
 {
@@ -628,6 +661,7 @@
 	atf_add_test_case fgrep_sanity
 	atf_add_test_case egrep_sanity
 	atf_add_test_case grep_sanity
+	atf_add_test_case ocolor_metadata
 	atf_add_test_case grep_nomatch_flags
 	atf_add_test_case binary_flags
 	atf_add_test_case badcontext
Index: head/usr.bin/grep/grep.h
===================================================================
--- head/usr.bin/grep/grep.h
+++ head/usr.bin/grep/grep.h
@@ -90,6 +90,7 @@
 };
 
 struct str {
+	off_t		 boff;
 	off_t		 off;
 	size_t		 len;
 	char		*dat;
Index: head/usr.bin/grep/queue.c
===================================================================
--- head/usr.bin/grep/queue.c
+++ head/usr.bin/grep/queue.c
@@ -65,6 +65,7 @@
 	item->data.dat = grep_malloc(sizeof(char) * x->len);
 	item->data.len = x->len;
 	item->data.line_no = x->line_no;
+	item->data.boff = x->boff;
 	item->data.off = x->off;
 	memcpy(item->data.dat, x->dat, x->len);
 	item->data.file = x->file;
Index: head/usr.bin/grep/util.c
===================================================================
--- head/usr.bin/grep/util.c
+++ head/usr.bin/grep/util.c
@@ -61,11 +61,12 @@
  * other useful bits
  */
 struct parsec {
-	regmatch_t matches[MAX_LINE_MATCHES];	/* Matches made */
-	struct str ln;				/* Current line */
-	size_t lnstart;				/* Start of line processing */
-	size_t matchidx;			/* Latest used match index */
-	bool binary;				/* Binary file? */
+	regmatch_t	matches[MAX_LINE_MATCHES];	/* Matches made */
+	struct str	ln;				/* Current line */
+	size_t		lnstart;			/* Position in line */
+	size_t		matchidx;			/* Latest match index */
+	int		printed;			/* Metadata printed? */
+	bool		binary;				/* Binary file? */
 };
 
 
@@ -233,8 +234,10 @@
 	strcpy(pc.ln.file, fn);
 	pc.ln.line_no = 0;
 	pc.ln.len = 0;
+	pc.ln.boff = 0;
 	pc.ln.off = -1;
 	pc.binary = f->binary;
+	pc.printed = 0;
 	tail = 0;
 	last_outed = 0;
 	same_file = false;
@@ -248,9 +251,11 @@
 	mcount = mlimit;
 
 	for (c = 0;  c == 0 || !(lflag || qflag); ) {
-		/* Reset match count and line start for every line processed */
+		/* Reset per-line statistics */
+		pc.printed = 0;
 		pc.matchidx = 0;
 		pc.lnstart = 0;
+		pc.ln.boff = 0;
 		pc.ln.off += pc.ln.len + 1;
 		if ((pc.ln.dat = grep_fgetln(f, &pc.ln.len)) == NULL ||
 		    pc.ln.len == 0) {
@@ -305,7 +310,7 @@
 		if (t != 0 && doctx) {
 			/* Deal with any -A context */
 			if (tail > 0) {
-				printline(&pc, '-');
+				grep_printline(&pc.ln, '-');
 				tail--;
 				if (Bflag > 0)
 					clearqueue();
@@ -607,7 +612,7 @@
 	if (bflag) {
 		if (printsep)
 			putchar(sep);
-		printf("%lld", (long long)line->off);
+		printf("%lld", (long long)(line->off + line->boff));
 		printsep = true;
 	}
 	if (printsep)
@@ -632,13 +637,22 @@
 
 	/* --color and -o */
 	if ((oflag || color) && matchidx > 0) {
-		printline_metadata(&pc->ln, sep);
+		/* Only print metadata once per line if --color */
+		if (!oflag && pc->printed == 0)
+			printline_metadata(&pc->ln, sep);
 		for (i = 0; i < matchidx; i++) {
 			match = pc->matches[i];
 			/* Don't output zero length matches */
 			if (match.rm_so == match.rm_eo)
 				continue;
-			if (!oflag)
+			/*
+			 * Metadata is printed on a per-line basis, so every
+			 * match gets file metadata with the -o flag.
+			 */
+			if (oflag) {
+				pc->ln.boff = match.rm_so;
+				printline_metadata(&pc->ln, sep);
+			} else
 				fwrite(pc->ln.dat + a, match.rm_so - a, 1,
 				    stdout);
 			if (color)
@@ -659,4 +673,5 @@
 		}
 	} else
 		grep_printline(&pc->ln, sep);
+	pc->printed++;
 }