diff --git a/fs_mgr/libsnapshot/snapuserd/dm-snapshot-merge/snapuserd_readahead.cpp b/fs_mgr/libsnapshot/snapuserd/dm-snapshot-merge/snapuserd_readahead.cpp index 3bb7a0a07..c201b23dc 100644 --- a/fs_mgr/libsnapshot/snapuserd/dm-snapshot-merge/snapuserd_readahead.cpp +++ b/fs_mgr/libsnapshot/snapuserd/dm-snapshot-merge/snapuserd_readahead.cpp @@ -246,9 +246,15 @@ bool ReadAheadThread::ReconstructDataFromCow() { int num_ops = 0; int total_blocks_merged = 0; + // This memcpy is important as metadata_buffer_ will be an unaligned address and will fault + // on 32-bit systems + std::unique_ptr metadata_buffer = + std::make_unique(snapuserd_->GetBufferMetadataSize()); + memcpy(metadata_buffer.get(), metadata_buffer_, snapuserd_->GetBufferMetadataSize()); + while (true) { struct ScratchMetadata* bm = reinterpret_cast( - (char*)metadata_buffer_ + metadata_offset); + (char*)metadata_buffer.get() + metadata_offset); // Done reading metadata if (bm->new_block == 0 && bm->file_offset == 0) { diff --git a/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_readahead.cpp b/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_readahead.cpp index 40e7242cd..9e8ccfb1e 100644 --- a/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_readahead.cpp +++ b/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_readahead.cpp @@ -121,9 +121,15 @@ bool ReadAhead::ReconstructDataFromCow() { int num_ops = 0; int total_blocks_merged = 0; + // This memcpy is important as metadata_buffer_ will be an unaligned address and will fault + // on 32-bit systems + std::unique_ptr metadata_buffer = + std::make_unique(snapuserd_->GetBufferMetadataSize()); + memcpy(metadata_buffer.get(), metadata_buffer_, snapuserd_->GetBufferMetadataSize()); + while (true) { struct ScratchMetadata* bm = reinterpret_cast( - (char*)metadata_buffer_ + metadata_offset); + (char*)metadata_buffer.get() + metadata_offset); // Done reading metadata if (bm->new_block == 0 && bm->file_offset == 0) {