grub: add structure initialization in zstd

This patch adds initialization of a structure in grub's zstd, which
might be left uninitialized by the compiler. 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: 370ea660d476bda0d4f45520815396036648d87a)

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, 35 insertions, 0 deletions

diff --git a/meta/recipes-bsp/grub/files/0014-zstd-Initialize-seq_t-structure-fully.patch b/meta/recipes-bsp/grub/files/0014-zstd-Initialize-seq_t-structure-fully.patch
new file mode 100644
index 0000000000..19d881c1ca
--- /dev/null
+++ b/meta/recipes-bsp/grub/files/0014-zstd-Initialize-seq_t-structure-fully.patch
@@ -0,0 +1,34 @@
+From f55ffe6bd8b844a8cd9956702f42ac2eb96ad56f Mon Sep 17 00:00:00 2001
+From: Darren Kenny <darren.kenny@oracle.com>
+Date: Thu, 5 Nov 2020 10:29:59 +0000
+Subject: [PATCH] zstd: Initialize seq_t structure fully
+
+While many compilers will initialize this to zero, not all will, so it
+is better to be sure that fields not being explicitly set are at known
+values, and there is code that checks this fields value elsewhere in the
+code.
+
+Fixes: CID 292440
+
+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=2777cf4466719921dbe4b30af358a75e7d76f217]
+Signed-off-by: Marta Rybczynska <marta.rybczynska@huawei.com>
+---
+ grub-core/lib/zstd/zstd_decompress.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/grub-core/lib/zstd/zstd_decompress.c b/grub-core/lib/zstd/zstd_decompress.c
+index 711b5b6..e4b5670 100644
+--- a/grub-core/lib/zstd/zstd_decompress.c
++++ b/grub-core/lib/zstd/zstd_decompress.c
+@@ -1325,7 +1325,7 @@ typedef enum { ZSTD_lo_isRegularOffset, ZSTD_lo_isLongOffset=1 } ZSTD_longOffset
+ FORCE_INLINE_TEMPLATE seq_t
+ ZSTD_decodeSequence(seqState_t* seqState, const ZSTD_longOffset_e longOffsets)
+ {
+-    seq_t seq;
++    seq_t seq = {0};
+     U32 const llBits = seqState->stateLL.table[seqState->stateLL.state].nbAdditionalBits;
+     U32 const mlBits = seqState->stateML.table[seqState->stateML.state].nbAdditionalBits;
+     U32 const ofBits = seqState->stateOffb.table[seqState->stateOffb.state].nbAdditionalBits;
diff --git a/meta/recipes-bsp/grub/grub2.inc b/meta/recipes-bsp/grub/grub2.inc
index 1906a28f30..7cf4d64149 100644
--- a/meta/recipes-bsp/grub/grub2.inc
+++ b/meta/recipes-bsp/grub/grub2.inc
@@ -60,6 +60,7 @@ SRC_URI = "${GNU_MIRROR}/grub/grub-${PV}.tar.gz \
            file://0011-gnulib-regexec-Fix-possible-null-dereference.patch \
            file://0012-gnulib-regcomp-Fix-uninitialized-re_token.patch \
            file://0013-io-lzopio-Resolve-unnecessary-self-assignment-errors.patch \
+           file://0014-zstd-Initialize-seq_t-structure-fully.patch \
            "
 SRC_URI[md5sum] = "5ce674ca6b2612d8939b9e6abed32934"
 SRC_URI[sha256sum] = "f10c85ae3e204dbaec39ae22fa3c5e99f0665417e91c2cb49b7e5031658ba6ea"