diff mbox series

[v3,3/6] btrfs-progs: original check: Add ability to detect bad dev extents

Message ID 20181008123044.13413-4-wqu@suse.com (mailing list archive)
State New, archived
Headers show
Series btrfs-progs: check: Detect invalid dev extents and device items | expand

Commit Message

Qu Wenruo Oct. 8, 2018, 12:30 p.m. UTC 
Unlike lowmem mode check, we don't have good place for original mode to
check overlap dev extents.

So this patch introduces a new function, btrfs_check_dev_extents(), to
handle possible bad dev extents.

Reported-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
---
 check/main.c | 99 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 99 insertions(+)

Comments

Su Yue Oct. 9, 2018, 2:01 a.m. UTC | #1 
On 10/8/18 8:30 PM, Qu Wenruo wrote:
> Unlike lowmem mode check, we don't have good place for original mode to
> check overlap dev extents.
> 
> So this patch introduces a new function, btrfs_check_dev_extents(), to
> handle possible bad dev extents.
> 
> Reported-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com>
> Signed-off-by: Qu Wenruo <wqu@suse.com>

Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
> ---
>   check/main.c | 99 ++++++++++++++++++++++++++++++++++++++++++++++++++++
>   1 file changed, 99 insertions(+)
> 
> diff --git a/check/main.c b/check/main.c
> index bc2ee22f7943..ff9a785ce555 100644
> --- a/check/main.c
> +++ b/check/main.c
> @@ -8224,6 +8224,99 @@ out:
>   	return ret;
>   }
>   
> +/*
> + * Check if all dev extents are valid (not overlap nor beyond device
> + * boundary).
> + *
> + * Dev extents <-> chunk cross checking is already done in check_chunks().
> + */
> +static int check_dev_extents(struct btrfs_fs_info *fs_info)
> +{
> +	struct btrfs_path path;
> +	struct btrfs_key key;
> +	struct btrfs_root *dev_root = fs_info->dev_root;
> +	int ret;
> +	u64 prev_devid = 0;
> +	u64 prev_dev_ext_end = 0;
> +
> +	btrfs_init_path(&path);
> +
> +	key.objectid = 1;
> +	key.type = BTRFS_DEV_EXTENT_KEY;
> +	key.offset = 0;
> +
> +	ret = btrfs_search_slot(NULL, dev_root, &key, &path, 0, 0);
> +	if (ret < 0) {
> +		error("failed to search device tree: %s", strerror(-ret));
> +		goto out;
> +	}
> +	if (path.slots[0] >= btrfs_header_nritems(path.nodes[0])) {
> +		ret = btrfs_next_leaf(dev_root, &path);
> +		if (ret < 0) {
> +			error("failed to find next leaf: %s", strerror(-ret));
> +			goto out;
> +		}
> +		if (ret > 0) {
> +			ret = 0;
> +			goto out;
> +		}
> +	}
> +
> +	while (1) {
> +		struct btrfs_dev_extent *dev_ext;
> +		struct btrfs_device *dev;
> +		u64 devid;
> +		u64 physical_offset;
> +		u64 physical_len;
> +
> +		btrfs_item_key_to_cpu(path.nodes[0], &key, path.slots[0]);
> +		if (key.type != BTRFS_DEV_EXTENT_KEY)
> +			break;
> +		dev_ext = btrfs_item_ptr(path.nodes[0], path.slots[0],
> +					 struct btrfs_dev_extent);
> +		devid = key.objectid;
> +		physical_offset = key.offset;
> +		physical_len = btrfs_dev_extent_length(path.nodes[0], dev_ext);
> +
> +		dev = btrfs_find_device(fs_info, devid, NULL, NULL);
> +		if (!dev) {
> +			error("failed to find device with devid %llu", devid);
> +			ret = -EUCLEAN;
> +			goto out;
> +		}
> +		if (prev_devid == devid && prev_dev_ext_end > physical_offset) {
> +			error(
> +"dev extent devid %llu physical offset %llu overlap with previous dev extent end %llu",
> +			      devid, physical_offset, prev_dev_ext_end);
> +			ret = -EUCLEAN;
> +			goto out;
> +		}
> +		if (physical_offset + physical_len > dev->total_bytes) {
> +			error(
> +"dev extent devid %llu physical offset %llu len %llu is beyond device boudnary %llu",
> +			      devid, physical_offset, physical_len,
> +			      dev->total_bytes);
> +			ret = -EUCLEAN;
> +			goto out;
> +		}
> +		prev_devid = devid;
> +		prev_dev_ext_end = physical_offset + physical_len;
> +
> +		ret = btrfs_next_item(dev_root, &path);
> +		if (ret < 0) {
> +			error("failed to find next leaf: %s", strerror(-ret));
> +			goto out;
> +		}
> +		if (ret > 0) {
> +			ret = 0;
> +			break;
> +		}
> +	}
> +out:
> +	btrfs_release_path(&path);
> +	return ret;
> +}
> +
>   static int check_chunks_and_extents(struct btrfs_fs_info *fs_info)
>   {
>   	struct rb_root dev_cache;
> @@ -8318,6 +8411,12 @@ again:
>   		goto out;
>   	}
>   
> +	ret = check_dev_extents(fs_info);
> +	if (ret < 0) {
> +		err = ret;
> +		goto out;
> +	}
> +
>   	ret = check_chunks(&chunk_cache, &block_group_cache,
>   			   &dev_extent_cache, NULL, NULL, NULL, 0);
>   	if (ret) {
>
diff mbox series

Patch

diff --git a/check/main.c b/check/main.c
index bc2ee22f7943..ff9a785ce555 100644
--- a/check/main.c
+++ b/check/main.c
@@ -8224,6 +8224,99 @@  out:
 	return ret;
 }
 
+/*
+ * Check if all dev extents are valid (not overlap nor beyond device
+ * boundary).
+ *
+ * Dev extents <-> chunk cross checking is already done in check_chunks().
+ */
+static int check_dev_extents(struct btrfs_fs_info *fs_info)
+{
+	struct btrfs_path path;
+	struct btrfs_key key;
+	struct btrfs_root *dev_root = fs_info->dev_root;
+	int ret;
+	u64 prev_devid = 0;
+	u64 prev_dev_ext_end = 0;
+
+	btrfs_init_path(&path);
+
+	key.objectid = 1;
+	key.type = BTRFS_DEV_EXTENT_KEY;
+	key.offset = 0;
+
+	ret = btrfs_search_slot(NULL, dev_root, &key, &path, 0, 0);
+	if (ret < 0) {
+		error("failed to search device tree: %s", strerror(-ret));
+		goto out;
+	}
+	if (path.slots[0] >= btrfs_header_nritems(path.nodes[0])) {
+		ret = btrfs_next_leaf(dev_root, &path);
+		if (ret < 0) {
+			error("failed to find next leaf: %s", strerror(-ret));
+			goto out;
+		}
+		if (ret > 0) {
+			ret = 0;
+			goto out;
+		}
+	}
+
+	while (1) {
+		struct btrfs_dev_extent *dev_ext;
+		struct btrfs_device *dev;
+		u64 devid;
+		u64 physical_offset;
+		u64 physical_len;
+
+		btrfs_item_key_to_cpu(path.nodes[0], &key, path.slots[0]);
+		if (key.type != BTRFS_DEV_EXTENT_KEY)
+			break;
+		dev_ext = btrfs_item_ptr(path.nodes[0], path.slots[0],
+					 struct btrfs_dev_extent);
+		devid = key.objectid;
+		physical_offset = key.offset;
+		physical_len = btrfs_dev_extent_length(path.nodes[0], dev_ext);
+
+		dev = btrfs_find_device(fs_info, devid, NULL, NULL);
+		if (!dev) {
+			error("failed to find device with devid %llu", devid);
+			ret = -EUCLEAN;
+			goto out;
+		}
+		if (prev_devid == devid && prev_dev_ext_end > physical_offset) {
+			error(
+"dev extent devid %llu physical offset %llu overlap with previous dev extent end %llu",
+			      devid, physical_offset, prev_dev_ext_end);
+			ret = -EUCLEAN;
+			goto out;
+		}
+		if (physical_offset + physical_len > dev->total_bytes) {
+			error(
+"dev extent devid %llu physical offset %llu len %llu is beyond device boudnary %llu",
+			      devid, physical_offset, physical_len,
+			      dev->total_bytes);
+			ret = -EUCLEAN;
+			goto out;
+		}
+		prev_devid = devid;
+		prev_dev_ext_end = physical_offset + physical_len;
+
+		ret = btrfs_next_item(dev_root, &path);
+		if (ret < 0) {
+			error("failed to find next leaf: %s", strerror(-ret));
+			goto out;
+		}
+		if (ret > 0) {
+			ret = 0;
+			break;
+		}
+	}
+out:
+	btrfs_release_path(&path);
+	return ret;
+}
+
 static int check_chunks_and_extents(struct btrfs_fs_info *fs_info)
 {
 	struct rb_root dev_cache;
@@ -8318,6 +8411,12 @@  again:
 		goto out;
 	}
 
+	ret = check_dev_extents(fs_info);
+	if (ret < 0) {
+		err = ret;
+		goto out;
+	}
+
 	ret = check_chunks(&chunk_cache, &block_group_cache,
 			   &dev_extent_cache, NULL, NULL, NULL, 0);
 	if (ret) {