[PATCH] btrfs-progs: volumes: check stripe end against device boundary

[Qu Wenruo <wqu@suse.com>]

There is a report of kernel generationg READ bio access beyond device
boundary.

To make sure it's not caused by on-disk chunk items, add extra stripe
check against device total_bytes so that btrfs check can detect such
problem early on.

Signed-off-by: Qu Wenruo <wqu@suse.com>
---
 volumes.c | 29 +++++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)

diff --git a/volumes.c b/volumes.c
index 538f799e7211..0467dd63d5cb 100644
--- a/volumes.c
+++ b/volumes.c
@@ -1843,6 +1843,7 @@ int btrfs_check_chunk_valid(struct btrfs_fs_info *fs_info,
 	u64 type;
 	u32 chunk_ondisk_size;
 	u32 sectorsize = fs_info->sectorsize;
+	int i;
 
 	/*
 	 * Basic chunk item size check.  Note that btrfs_chunk already contains
@@ -1953,6 +1954,34 @@ int btrfs_check_chunk_valid(struct btrfs_fs_info *fs_info,
 		return -EIO;
 	}
 
+	/*
+	 * Stripe check against device boundary
+	 */
+	for (i = 0; i < num_stripes; i++) {
+		struct btrfs_device *dev;
+		u64 physical;
+		u64 devid;
+		u64 stripe_len;
+
+		devid = btrfs_stripe_devid_nr(leaf, chunk, i);
+		physical = btrfs_stripe_offset_nr(leaf, chunk, i);
+		stripe_len = calc_stripe_length(type, length, num_stripes);
+		dev = btrfs_find_device(fs_info, devid, NULL, NULL);
+		/*
+		 * Device not found? Then we may be in the bootstrap process for
+		 * system chunks. Skip.
+		 */
+		if (!dev)
+			continue;
+		if (physical + stripe_len > dev->total_bytes) {
+			error(
+"chunk %llu stripe %d is beyond device boundary: devid %llu total_bytes %llu stripe start %llu len %llu",
+				logical, i, devid, dev->total_bytes, physical,
+				stripe_len);
+			return -EUCLEAN;
+		}
+	}
+
 	return 0;
 }
 
-- 
2.28.0