mirrors/poky
1
0
Fork 0
mirror of https://git.yoctoproject.org/poky synced 2026-06-03 01:40:07 +00:00
Code Issues Projects Releases Wiki Activity

grub: add a fix for a possible negative shift

Browse Source 
This patch adds a fix for a possible negative shift in grub's zfs.
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: d5a93d55b5f3bfd890aa2925869d2a5ba4299801)

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>
This commit is contained in:
Marta Rybczynska
2022-02-18 11:05:29 +01:00
committed by Richard Purdie
parent 3348511b94
commit b461e69025
2 changed files with 43 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files
meta/recipes-bsp/grub/files/0021-zfs-Fix-possible-negative-shift-operation.patch
+42
View File
@@ -0,0 +1,42 @@
From c757779e5d09719666c3b155afd2421978a107bd Mon Sep 17 00:00:00 2001
From: Darren Kenny <darren.kenny@oracle.com>
Date: Tue, 24 Nov 2020 16:41:49 +0000
Subject: [PATCH] zfs: Fix possible negative shift operation
While it is possible for the return value from zfs_log2() to be zero
(0), it is quite unlikely, given that the previous assignment to blksz
is shifted up by SPA_MINBLOCKSHIFT (9) before 9 is subtracted at the
assignment to epbs.
But, while unlikely during a normal operation, it may be that a carefully
crafted ZFS filesystem could result in a zero (0) value to the
dn_datalbkszsec field, which means that the shift left does nothing
and assigns zero (0) to blksz, resulting in a negative epbs value.
Fixes: CID 73608
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=a02091834d3e167320d8a262ff04b8e83c5e616d]
Signed-off-by: Marta Rybczynska <marta.rybczynska@huawei.com>
---
grub-core/fs/zfs/zfs.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/grub-core/fs/zfs/zfs.c b/grub-core/fs/zfs/zfs.c
index 36d0373..0c42cba 100644
--- a/grub-core/fs/zfs/zfs.c
+++ b/grub-core/fs/zfs/zfs.c
@@ -2667,6 +2667,11 @@ dnode_get (dnode_end_t * mdn, grub_uint64_t objnum, grub_uint8_t type,
blksz = grub_zfs_to_cpu16 (mdn->dn.dn_datablkszsec,
mdn->endian) << SPA_MINBLOCKSHIFT;
epbs = zfs_log2 (blksz) - DNODE_SHIFT;
+
+ /* While this should never happen, we should check that epbs is not negative. */
+ if (epbs < 0)
+ epbs = 0;
+
blkid = objnum >> epbs;
idx = objnum & ((1 << epbs) - 1);
meta/recipes-bsp/grub/grub2.inc
+1
View File
@@ -67,6 +67,7 @@ SRC_URI = "${GNU_MIRROR}/grub/grub-${PV}.tar.gz \
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 \
file://0021-zfs-Fix-possible-negative-shift-operation.patch \
"
SRC_URI[md5sum] = "5ce674ca6b2612d8939b9e6abed32934"
SRC_URI[sha256sum] = "f10c85ae3e204dbaec39ae22fa3c5e99f0665417e91c2cb49b7e5031658ba6ea"