grub: fix an error check

This patch fixes an error check in grub's zfsinfo. 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: ec842684b572e5fe940762e1b5b4339e6ef6a0ba)

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, 36 insertions, 0 deletions

diff --git a/meta/recipes-bsp/grub/files/0024-zfsinfo-Correct-a-check-for-error-allocating-memory.patch b/meta/recipes-bsp/grub/files/0024-zfsinfo-Correct-a-check-for-error-allocating-memory.patch
new file mode 100644
index 0000000000..555dc19168
--- /dev/null
+++ b/meta/recipes-bsp/grub/files/0024-zfsinfo-Correct-a-check-for-error-allocating-memory.patch
@@ -0,0 +1,35 @@
+From b085da8efda9b81f94aa197ee045226563554fdf Mon Sep 17 00:00:00 2001
+From: Darren Kenny <darren.kenny@oracle.com>
+Date: Thu, 26 Nov 2020 10:56:45 +0000
+Subject: [PATCH] zfsinfo: Correct a check for error allocating memory
+
+While arguably the check for grub_errno is correct, we should really be
+checking the return value from the function since it is always possible
+that grub_errno was set elsewhere, making this code behave incorrectly.
+
+Fixes: CID 73668
+
+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=7aab03418ec6a9b991aa44416cb2585aff4e7972]
+Signed-off-by: Marta Rybczynska <marta.rybczynska@huawei.com>
+---
+ grub-core/fs/zfs/zfsinfo.c | 4 ++--
+ 1 file changed, 2 insertions(+), 2 deletions(-)
+
+diff --git a/grub-core/fs/zfs/zfsinfo.c b/grub-core/fs/zfs/zfsinfo.c
+index c8a28ac..bf29180 100644
+--- a/grub-core/fs/zfs/zfsinfo.c
++++ b/grub-core/fs/zfs/zfsinfo.c
+@@ -358,8 +358,8 @@ grub_cmd_zfs_bootfs (grub_command_t cmd __attribute__ ((unused)), int argc,
+     return grub_error (GRUB_ERR_BAD_ARGUMENT, N_("one argument expected"));
+ 
+   devname = grub_file_get_device_name (args[0]);
+-  if (grub_errno)
+-    return grub_errno;
++  if (devname == NULL)
++    return GRUB_ERR_OUT_OF_MEMORY;
+ 
+   dev = grub_device_open (devname);
+   grub_free (devname);
diff --git a/meta/recipes-bsp/grub/grub2.inc b/meta/recipes-bsp/grub/grub2.inc
index 9158fc7f50..a660c069db 100644
--- a/meta/recipes-bsp/grub/grub2.inc
+++ b/meta/recipes-bsp/grub/grub2.inc
@@ -70,6 +70,7 @@ SRC_URI = "${GNU_MIRROR}/grub/grub-${PV}.tar.gz \
            file://0021-zfs-Fix-possible-negative-shift-operation.patch \
            file://0022-zfs-Fix-resource-leaks-while-constructing-path.patch \
            file://0023-zfs-Fix-possible-integer-overflows.patch \
+           file://0024-zfsinfo-Correct-a-check-for-error-allocating-memory.patch \
            "
 SRC_URI[md5sum] = "5ce674ca6b2612d8939b9e6abed32934"
 SRC_URI[sha256sum] = "f10c85ae3e204dbaec39ae22fa3c5e99f0665417e91c2cb49b7e5031658ba6ea"