diff mbox series

[v5,2/4] generic/574: corrupt btrfs merkle tree data

Message ID ce1febfd4247357e89bf18c15115ad08bf1870d7.1631558495.git.boris@bur.io (mailing list archive)
State New
Headers show
Series tests for btrfs fsverity | expand

Commit Message

Boris Burkov Sept. 13, 2021, 6:44 p.m. UTC
generic/574 has tests for corrupting the merkle tree data stored by the
filesystem. Since btrfs uses a different scheme for storing this data,
the existing logic for corrupting it doesn't work out of the box. Adapt
it to properly corrupt btrfs merkle items.

This test relies on the btrfs implementation of fsverity in the patch:
btrfs: initial fsverity support

and on btrfs-corrupt-block for corruption in the patches titled:
btrfs-progs: corrupt generic item data with btrfs-corrupt-block
btrfs-progs: expand corrupt_file_extent in btrfs-corrupt-block

Signed-off-by: Boris Burkov <boris@bur.io>
---
 common/verity | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)
diff mbox series

Patch

diff --git a/common/verity b/common/verity
index 7eb8d9b9..74163987 100644
--- a/common/verity
+++ b/common/verity
@@ -317,6 +317,24 @@  _fsv_scratch_corrupt_merkle_tree()
 		(( offset += ($(_get_filesize $file) + 65535) & ~65535 ))
 		_fsv_scratch_corrupt_bytes $file $offset
 		;;
+	btrfs)
+		local ino=$(stat -c '%i' $file)
+		_scratch_unmount
+		local byte=""
+		while read -n 1 byte; do
+			if [ -z $byte ]; then
+				break
+			fi
+			local ascii=$(printf "%d" "'$byte'")
+			# This command will find a Merkle tree item for the inode (-I $ino,37,0)
+			# in the default filesystem tree (-r 5) and corrupt one byte (-b 1) at
+			# $offset (-o $offset) with the ascii representation of the byte we read
+			# (-v $ascii)
+			$BTRFS_CORRUPT_BLOCK_PROG -r 5 -I $ino,37,0 -v $ascii -o $offset -b 1 $SCRATCH_DEV
+			(( offset += 1 ))
+		done
+		_scratch_mount
+		;;
 	*)
 		_fail "_fsv_scratch_corrupt_merkle_tree() unimplemented on $FSTYP"
 		;;