| From 20ab8cb44bc140a1dedda82a3fccdd45e9bc6929 Mon Sep 17 00:00:00 2001 |
| From: Daniel Axtens <dja@axtens.net> |
| Date: Mon, 18 Jan 2021 16:49:09 +1100 |
| Subject: [PATCH] fs/nilfs2: Reject too-large keys |
| |
| NILFS2 has up to 7 keys, per the data structure. Do not permit array |
| indices in excess of that. |
| |
| This catches some OOB reads. I don't know how controllable the invalidly |
| read data is or if that could be used later in the program. |
| |
| Signed-off-by: Daniel Axtens <dja@axtens.net> |
| Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com> |
| Signed-off-by: Stefan Sørensen <stefan.sorensen@spectralink.com> |
| --- |
| grub-core/fs/nilfs2.c | 7 ++++++- |
| 1 file changed, 6 insertions(+), 1 deletion(-) |
| |
| diff --git a/grub-core/fs/nilfs2.c b/grub-core/fs/nilfs2.c |
| index 7ed148d..fee2242 100644 |
| --- a/grub-core/fs/nilfs2.c |
| +++ b/grub-core/fs/nilfs2.c |
| @@ -569,6 +569,11 @@ grub_nilfs2_btree_lookup (struct grub_nilfs2_data *data, |
| static inline grub_uint64_t |
| grub_nilfs2_direct_lookup (struct grub_nilfs2_inode *inode, grub_uint64_t key) |
| { |
| + if (1 + key > 6) |
| + { |
| + grub_error (GRUB_ERR_BAD_FS, "key is too large"); |
| + return 0xffffffffffffffff; |
| + } |
| return grub_le_to_cpu64 (inode->i_bmap[1 + key]); |
| } |
| |
| @@ -584,7 +589,7 @@ grub_nilfs2_bmap_lookup (struct grub_nilfs2_data *data, |
| { |
| grub_uint64_t ptr; |
| ptr = grub_nilfs2_direct_lookup (inode, key); |
| - if (need_translate) |
| + if (ptr != ((grub_uint64_t) 0xffffffffffffffff) && need_translate) |
| ptr = grub_nilfs2_dat_translate (data, ptr); |
| return ptr; |
| } |
| -- |
| 2.14.2 |
| |