util-linux: backport a patch to address mkswap hangs

(From OE-Core rev: 4d50d6f708477da0a5314a3749275d87101374d9)

Signed-off-by: Alexander Kanavin <alex.kanavin@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/recipes-core/util-linux/util-linux.inc

@@ -35,5 +35,6 @@ SRC_URI = "${KERNELORG_MIRROR}/linux/utils/util-linux/v${MAJOR_VERSION}/util-lin
            file://run-ptest \
            file://display_testname_for_subtest.patch \
            file://avoid_parallel_tests.patch \
+           file://8a3a74160b96498d672e3652827aa7e6d7f3a120.patch \
            "
 SRC_URI[sha256sum] = "bd07b7e98839e0359842110525a3032fdb8eaf3a90bedde3dd1652d32d15cce5"

meta/recipes-core/util-linux/util-linux/8a3a74160b96498d672e3652827aa7e6d7f3a120.patch

@@ -0,0 +1,29 @@
+From 8a3a74160b96498d672e3652827aa7e6d7f3a120 Mon Sep 17 00:00:00 2001
+From: Karel Zak <kzak@redhat.com>
+Date: Tue, 15 Jun 2021 12:04:43 +0200
+Subject: [PATCH] mkswap: fix holes detection (infinite loop and/or
+ stack-buffer-underflow)
+
+Reported-by: Brian Lane <bcl@redhat.com>
+Addresses: https://bugzilla.redhat.com/show_bug.cgi?id=1971877
+Fix: https://github.com/karelzak/util-linux/issues/1348
+Signed-off-by: Karel Zak <kzak@redhat.com>
+Upstream-Status: Backport
+Signed-off-by: Alexander Kanavin <alex.kanavin@gmail.com>
+---
+ disk-utils/mkswap.c | 2 ++
+ 1 file changed, 2 insertions(+)
+
+diff --git a/disk-utils/mkswap.c b/disk-utils/mkswap.c
+index 27374fd72..c45a3a317 100644
+--- a/disk-utils/mkswap.c
++++ b/disk-utils/mkswap.c
+@@ -267,6 +267,8 @@ static void check_extents(struct mkswap_control *ctl)
+ 			return;
+ 
+ 		n = fiemap->fm_mapped_extents;
++		if (n == 0)
++			break;
+ 
+ 		for (i = 0; i < n; i++) {
+ 			struct fiemap_extent *e = &fiemap->fm_extents[i];