36 lines
1.2 KiB
Diff
36 lines
1.2 KiB
Diff
|
From fb52b550be82812b6e9a4eeb0bc80bf1ae67de0b Mon Sep 17 00:00:00 2001
|
||
|
|
From: Daniel Axtens <dja@axtens.net>
|
||
|
|
Date: Mon, 18 Jan 2021 14:51:11 +1100
|
||
|
|
Subject: [PATCH] fs/jfs: Do not move to leaf level if name length is negative
|
||
|
|
|
||
|
|
Fuzzing JFS revealed crashes where a negative number would be passed
|
||
|
|
to le_to_cpu16_copy(). There it would be cast to a large positive number
|
||
|
|
and the copy would read and write off the end of the respective buffers.
|
||
|
|
|
||
|
|
Catch this at the top as well as the bottom of the loop.
|
||
|
|
|
||
|
|
Reference: http://git.savannah.gnu.org/cgit/grub.git/commit/?id=ffd5a46f68710e2781899d0be4d701429a5a817d
|
||
|
|
|
||
|
|
Signed-off-by: Daniel Axtens <dja@axtens.net>
|
||
|
|
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
|
||
|
|
---
|
||
|
|
grub-core/fs/jfs.c | 2 +-
|
||
|
|
1 file changed, 1 insertion(+), 1 deletion(-)
|
||
|
|
|
||
|
|
diff --git a/grub-core/fs/jfs.c b/grub-core/fs/jfs.c
|
||
|
|
index d5a6d65..e5bbda6 100644
|
||
|
|
--- a/grub-core/fs/jfs.c
|
||
|
|
+++ b/grub-core/fs/jfs.c
|
||
|
|
@@ -567,7 +567,7 @@ grub_jfs_getent (struct grub_jfs_diropen *diro)
|
||
|
|
|
||
|
|
/* Move down to the leaf level. */
|
||
|
|
nextent = leaf->next;
|
||
|
|
- if (leaf->next != 255)
|
||
|
|
+ if (leaf->next != 255 && len > 0)
|
||
|
|
do
|
||
|
|
{
|
||
|
|
next_leaf = &diro->next_leaf[nextent];
|
||
|
|
--
|
||
|
|
2.19.1
|
||
|
|
|