2015-02-26 15:58:51

by Quentin Casasnovas

[permalink] [raw]
Subject: [PATCH] Btrfs:__add_inode_ref: out of bounds memory read when looking for extended ref.

Improper arithmetics when calculting the address of the extended ref could
lead to an out of bounds memory read and kernel panic.

Signed-off-by: Quentin Casasnovas <[email protected]>
---
fs/btrfs/tree-log.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git fs/btrfs/tree-log.c fs/btrfs/tree-log.c
index 9a37f8b..c5b8ba3 100644
--- fs/btrfs/tree-log.c
+++ fs/btrfs/tree-log.c
@@ -1012,7 +1012,7 @@ again:
base = btrfs_item_ptr_offset(leaf, path->slots[0]);

while (cur_offset < item_size) {
- extref = (struct btrfs_inode_extref *)base + cur_offset;
+ extref = (struct btrfs_inode_extref *)(base + cur_offset);

victim_name_len = btrfs_inode_extref_name_len(leaf, extref);

--
2.0.5