grub: add a fix for a length check

This patch adds a fix for a volume name length check in grub's
hfsplus. It is a part of a security series [1].

[1] https://lists.gnu.org/archive/html/grub-devel/2021-03/msg00007.html

(From OE-Core rev: 29470a74b944921641cd5d84b88c359acba26ad4)

Signed-off-by: Marta Rybczynska <marta.rybczynska@huawei.com>
Signed-off-by: Steve Sakoman <steve@sakoman.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

2 files changed, 44 insertions, 0 deletions

diff --git a/meta/recipes-bsp/grub/files/0020-hfsplus-Check-that-the-volume-name-length-is-valid.patch b/meta/recipes-bsp/grub/files/0020-hfsplus-Check-that-the-volume-name-length-is-valid.patch
new file mode 100644
index 0000000000..eb459c547f
--- /dev/null
+++ b/meta/recipes-bsp/grub/files/0020-hfsplus-Check-that-the-volume-name-length-is-valid.patch
@@ -0,0 +1,43 @@
+From 7c1813eeec78892fa651046cc224ae4e80d0c94d Mon Sep 17 00:00:00 2001
+From: Darren Kenny <darren.kenny@oracle.com>
+Date: Fri, 23 Oct 2020 17:09:31 +0000
+Subject: [PATCH] hfsplus: Check that the volume name length is valid
+
+HFS+ documentation suggests that the maximum filename and volume name is
+255 Unicode characters in length.
+
+So, when converting from big-endian to little-endian, we should ensure
+that the name of the volume has a length that is between 0 and 255,
+inclusive.
+
+Fixes: CID 73641
+
+Signed-off-by: Darren Kenny <darren.kenny@oracle.com>
+Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
+
+Upstream-Status: Backport [https://git.savannah.gnu.org/cgit/grub.git/commit/?id=2298f6e0d951251bb9ca97d891d1bc8b74515f8c]
+Signed-off-by: Marta Rybczynska <marta.rybczynska@huawei.com>
+---
+ grub-core/fs/hfsplus.c | 9 +++++++++
+ 1 file changed, 9 insertions(+)
+
+diff --git a/grub-core/fs/hfsplus.c b/grub-core/fs/hfsplus.c
+index dae43be..03c3c4c 100644
+--- a/grub-core/fs/hfsplus.c
++++ b/grub-core/fs/hfsplus.c
+@@ -1007,6 +1007,15 @@ grub_hfsplus_label (grub_device_t device, char **label)
+     grub_hfsplus_btree_recptr (&data->catalog_tree, node, ptr);
+ 
+   label_len = grub_be_to_cpu16 (catkey->namelen);
++
++  /* Ensure that the length is >= 0. */
++  if (label_len < 0)
++    label_len = 0;
++
++  /* Ensure label length is at most 255 Unicode characters. */
++  if (label_len > 255)
++    label_len = 255;
++
+   label_name = grub_calloc (label_len, sizeof (*label_name));
+   if (!label_name)
+     {
diff --git a/meta/recipes-bsp/grub/grub2.inc b/meta/recipes-bsp/grub/grub2.inc
index 130f32551b..3c5274fd96 100644
--- a/meta/recipes-bsp/grub/grub2.inc
+++ b/meta/recipes-bsp/grub/grub2.inc
@@ -66,6 +66,7 @@ SRC_URI = "${GNU_MIRROR}/grub/grub-${PV}.tar.gz \
            file://0017-disk-ldm-If-failed-then-free-vg-variable-too.patch \
            file://0018-disk-ldm-Fix-memory-leak-on-uninserted-lv-references.patch \
            file://0019-disk-cryptodisk-Fix-potential-integer-overflow.patch \
+           file://0020-hfsplus-Check-that-the-volume-name-length-is-valid.patch \
            "
 SRC_URI[md5sum] = "5ce674ca6b2612d8939b9e6abed32934"
 SRC_URI[sha256sum] = "f10c85ae3e204dbaec39ae22fa3c5e99f0665417e91c2cb49b7e5031658ba6ea"