diff mbox series

btrfs: Transpose btrfs_close_devices/btrfs_mapping_tree_free in close_ctree

Message ID 20190212141314.9169-1-nborisov@suse.com (mailing list archive)
State New, archived
Headers show
Series btrfs: Transpose btrfs_close_devices/btrfs_mapping_tree_free in close_ctree | expand

Commit Message

Nikolay Borisov Feb. 12, 2019, 2:13 p.m. UTC
Following the introduction of the alloc_state tree, some of the callees
of btrfs_mapping_tree_free will have to interact with the btrfs_device
of the constituent devices. Enable this by moving the code responsible
for freeing devices after the last user (btrfs_mapping_tree_free).
Otherwise the kernel could crash due to UAF.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
---

Hello David, 

The following patch either needs to come before "btrfs: replace pending/pinned
chunks lists with io tree" or has to be squashed in said commit. I'd prefer it 
to be a separate patch to have the explanation of the order of functions in 
the commit log. 


 fs/btrfs/disk-io.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index f1c42d242d48..4f74942f1d97 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -4041,8 +4041,8 @@  void close_ctree(struct btrfs_fs_info *fs_info)
 		btrfsic_unmount(fs_info->fs_devices);
 #endif
 
-	btrfs_close_devices(fs_info->fs_devices);
 	btrfs_mapping_tree_free(&fs_info->mapping_tree);
+	btrfs_close_devices(fs_info->fs_devices);
 
 	percpu_counter_destroy(&fs_info->dirty_metadata_bytes);
 	percpu_counter_destroy(&fs_info->delalloc_bytes);