| From ffd5a46f68710e2781899d0be4d701429a5a817d 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. |
| |
| Signed-off-by: Daniel Axtens <dja@axtens.net> |
| Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com> |
| Signed-off-by: Stefan SΓΈrensen <stefan.sorensen@spectralink.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]; |
| -- |
| 2.14.2 |
| |