diff options
Diffstat (limited to 'fs/verity/open.c')
-rw-r--r-- | fs/verity/open.c | 20 |
1 files changed, 15 insertions, 5 deletions
diff --git a/fs/verity/open.c b/fs/verity/open.c index e0ef1a628394..83ccc3c13736 100644 --- a/fs/verity/open.c +++ b/fs/verity/open.c @@ -34,6 +34,7 @@ int fsverity_init_merkle_tree_params(struct merkle_tree_params *params, struct fsverity_hash_alg *hash_alg; int err; u64 blocks; + u64 blocks_in_level[FS_VERITY_MAX_LEVELS]; u64 offset; int level; @@ -94,17 +95,26 @@ int fsverity_init_merkle_tree_params(struct merkle_tree_params *params, } blocks = (blocks + params->hashes_per_block - 1) >> params->log_arity; - /* temporarily using level_start[] to store blocks in level */ - params->level_start[params->num_levels++] = blocks; + blocks_in_level[params->num_levels++] = blocks; } - params->level0_blocks = params->level_start[0]; + params->level0_blocks = blocks_in_level[0]; /* Compute the starting block of each level */ offset = 0; for (level = (int)params->num_levels - 1; level >= 0; level--) { - blocks = params->level_start[level]; params->level_start[level] = offset; - offset += blocks; + offset += blocks_in_level[level]; + } + + /* + * Since the data, and thus also the Merkle tree, cannot have more than + * ULONG_MAX pages, hash block indices can always fit in an + * 'unsigned long'. To be safe, explicitly check for it too. + */ + if (offset > ULONG_MAX) { + fsverity_err(inode, "Too many blocks in Merkle tree"); + err = -EFBIG; + goto out_err; } params->tree_size = offset << log_blocksize; |