From: Nikolay Borisov nborisov@suse.com
[ Upstream commit ff37c89f94be14b0e22a532d1e6d57187bfd5bb8 ]
This simplifies the code flow in read_one_chunk and makes error handling when handling missing devices a bit simpler by reducing it to a single check if something went wrong. No functional changes.
Reviewed-by: Su Yue l@damenly.su Signed-off-by: Nikolay Borisov nborisov@suse.com Reviewed-by: David Sterba dsterba@suse.com Signed-off-by: David Sterba dsterba@suse.com Stable-dep-of: 1742e1c90c3d ("btrfs: fix extent map use-after-free when handling missing device in read_one_chunk") Signed-off-by: Sasha Levin sashal@kernel.org --- fs/btrfs/volumes.c | 38 ++++++++++++++++++++++++-------------- 1 file changed, 24 insertions(+), 14 deletions(-)
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index c886ec81c5d0..c773ecba7c2d 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -7043,6 +7043,27 @@ static void warn_32bit_meta_chunk(struct btrfs_fs_info *fs_info, } #endif
+static struct btrfs_device *handle_missing_device(struct btrfs_fs_info *fs_info, + u64 devid, u8 *uuid) +{ + struct btrfs_device *dev; + + if (!btrfs_test_opt(fs_info, DEGRADED)) { + btrfs_report_missing_device(fs_info, devid, uuid, true); + return ERR_PTR(-ENOENT); + } + + dev = add_missing_dev(fs_info->fs_devices, devid, uuid); + if (IS_ERR(dev)) { + btrfs_err(fs_info, "failed to init missing device %llu: %ld", + devid, PTR_ERR(dev)); + return dev; + } + btrfs_report_missing_device(fs_info, devid, uuid, false); + + return dev; +} + static int read_one_chunk(struct btrfs_key *key, struct extent_buffer *leaf, struct btrfs_chunk *chunk) { @@ -7130,28 +7151,17 @@ static int read_one_chunk(struct btrfs_key *key, struct extent_buffer *leaf, BTRFS_UUID_SIZE); args.uuid = uuid; map->stripes[i].dev = btrfs_find_device(fs_info->fs_devices, &args); - if (!map->stripes[i].dev && - !btrfs_test_opt(fs_info, DEGRADED)) { - free_extent_map(em); - btrfs_report_missing_device(fs_info, devid, uuid, true); - return -ENOENT; - } if (!map->stripes[i].dev) { - map->stripes[i].dev = - add_missing_dev(fs_info->fs_devices, devid, - uuid); + map->stripes[i].dev = handle_missing_device(fs_info, + devid, uuid); if (IS_ERR(map->stripes[i].dev)) { free_extent_map(em); - btrfs_err(fs_info, - "failed to init missing dev %llu: %ld", - devid, PTR_ERR(map->stripes[i].dev)); return PTR_ERR(map->stripes[i].dev); } - btrfs_report_missing_device(fs_info, devid, uuid, false); } + set_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &(map->stripes[i].dev->dev_state)); - }
write_lock(&map_tree->lock);