Btrfs: fix use after free when close_ctree frees the orphan_rsv
Near the end of close_ctree, we're calling btrfs_free_block_rsv
to free up the orphan rsv. The problem is this call updates the
space_info, which has already been freed.
This adds a new __ function that directly calls kfree instead of trying
to update the space infos.
Signed-off-by: Chris Mason <clm@fb.com>
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 83051fa..10b6a75 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -3470,6 +3470,7 @@
unsigned short type);
void btrfs_free_block_rsv(struct btrfs_root *root,
struct btrfs_block_rsv *rsv);
+void __btrfs_free_block_rsv(struct btrfs_block_rsv *rsv);
int btrfs_block_rsv_add(struct btrfs_root *root,
struct btrfs_block_rsv *block_rsv, u64 num_bytes,
enum btrfs_reserve_flush_enum flush);
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index b5e3d5f..62cd3b6 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -3766,7 +3766,7 @@
btrfs_free_stripe_hash_table(fs_info);
- btrfs_free_block_rsv(root, root->orphan_block_rsv);
+ __btrfs_free_block_rsv(root->orphan_block_rsv);
root->orphan_block_rsv = NULL;
lock_chunks(root);
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 02c2b29..875ba51 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -4918,6 +4918,11 @@
kfree(rsv);
}
+void __btrfs_free_block_rsv(struct btrfs_block_rsv *rsv)
+{
+ kfree(rsv);
+}
+
int btrfs_block_rsv_add(struct btrfs_root *root,
struct btrfs_block_rsv *block_rsv, u64 num_bytes,
enum btrfs_reserve_flush_enum flush)