Segmentation Fault During PIRProcessDatabase Execution

[alexlin-gogolook]

Environment

• macOS 15.0
• Xcode 16.0
• SwiftProtobuf 1.28.1

Description

I followed the steps outlined in the TestingInstructions.md. When I executed the command:

ConstructDatabase --icon-directory icons input.txtpb block.binpb identity.binpb

I encountered an error. It seems that there is an EXC_BAD_ACCESS happening on line 61 of ConstructDatabase.swift at the call to example.textFormatString().

To troubleshoot, I commented out the exampleIdentities and directly initialized inputIdentities instead of decoding it from textFormatString. After this change, I was able to generate block.binpb and identity.binpb.

However, when I followed the instructions further and executed:

PIRProcessDatabase block-config.json

I encountered the following error:

2024-09-30T18:03:26+0800 info PIRProcessDatabase : [PIRProcessDatabase] Processing database with configuration: {
  "algorithm" : "mulPir",
  "cuckooTableConfig" : {
    "bucketCount" : {
      "allowExpansion" : {
        "expansionFactor" : 1.1,
        "targetLoadFactor" : 0.9
      }
    },
    "hashFunctionCount" : 2,
    "maxEvictionCount" : 100,
    "maxSerializedBucketSize" : 1024,
    "multipleTables" : true,
    "slotCount" : 255
  },
  "inputDatabase" : "block.binpb",
  "keyCompression" : "noCompression",
  "outputDatabase" : "block-SHARD_ID.bin",
  "outputPirParameters" : "block-SHARD_ID.params.txtpb",
  "rlweParameters" : "n_4096_logq_27_28_28_logt_5",
  "sharding" : {
    "entryCountPerShard" : 1000
  },
  "trialsPerShard" : 5,
  "useMaxSerializedBucketSize" : false
}
2024-09-30T18:03:26+0800 info PIRProcessDatabase : [PIRProcessDatabase] Sharded database into 1 shards
2024-09-30T18:03:26+0800 info PIRProcessDatabase : [PIRProcessDatabase] Processing shard 0 with 3 rows
2024-09-30T18:03:26+0800 info PIRProcessDatabase : [PIRProcessDatabase] Created cuckoo table CuckooTableInformation(entryCount: 3, bucketCount: 2, emptyBucketCount: 1, loadFactor: 0.017089844)
2024-09-30T18:03:26+0800 info PIRProcessDatabase : [PIRProcessDatabase] Validating shard 0
zsh: segmentation fault  PIRProcessDatabase block-config.json

Any insight into what might be causing the segmentation fault or the initial EXC_BAD_ACCESS would be greatly appreciated!

[fboemer]

Any insight into what might be causing the segmentation fault or the initial EXC_BAD_ACCESS would be greatly appreciated!

Can you run this command with lldb? I.e., run

lldb PIRProcessDatabase block-config.json

Then, in the (lldb) prompt, enter run,

(lldb) run

Hopefully, you'll see the crash, and be able to enter backtrace.

(lldb) backtrace

which will return a backtrace of the issue.
If you can post the backtrace here, this will help us diagnose what the issue is.

[alexlin-gogolook]

Thank you for your reply.

Backtrace:

* thread #1, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x10)
  * frame #0: 0x000000019473975c libswiftCore.dylib`swift_getAssociatedTypeWitness + 28
    frame #1: 0x000000010025bd44 PIRProcessDatabase`BinaryEncodingSizeVisitor.visitMapField<SwiftProtobuf.ProtobufUInt64, HomomorphicEncryptionProtobuf.Apple_SwiftHomomorphicEncryption_V1_SerializedKeySwitchKey>(fieldType=SwiftProtobuf._ProtobufMessageMap<τ_0_0, τ_0_1>, value=Swift.Dictionary<Swift.UInt64, HomomorphicEncryptionProtobuf.Apple_SwiftHomomorphicEncryption_V1_SerializedKeySwitchKey> @ 0x0000000115e04300, fieldNumber=1) at <stdin>:0 [opt]
    frame #2: 0x000000010025ca38 PIRProcessDatabase`protocol witness for Visitor.visitMapField<A, B>(fieldType:value:fieldNumber:) in conformance BinaryEncodingSizeVisitor at <compiler-generated>:0 [opt]
    frame #3: 0x000000010017cb24 PIRProcessDatabase`Apple_SwiftHomomorphicEncryption_V1_SerializedGaloisKey.traverse<SwiftProtobuf.BinaryEncodingSizeVisitor>(visitor=(serializedSize = 0)) at apple_swift_homomorphic_encryption_v1_he.pb.swift:694:19 [opt]
    frame #4: 0x000000010017cd50 PIRProcessDatabase`protocol witness for Message.traverse<A>(visitor:) in conformance Apple_SwiftHomomorphicEncryption_V1_SerializedGaloisKey at <compiler-generated>:0 [opt]
    frame #5: 0x000000010028cabc PIRProcessDatabase`Message.serializedDataSize() at Message+BinaryAdditions.swift:74:9 [opt]
    frame #6: 0x000000010025a550 PIRProcessDatabase`BinaryEncodingSizeVisitor.visitSingularMessageField<τ_0_0>(value=<unavailable>, fieldNumber=<unavailable>) at BinaryEncodingSizeVisitor.swift:351:33 [opt]
    frame #7: 0x000000010025c768 PIRProcessDatabase`protocol witness for Visitor.visitSingularMessageField<A>(value:fieldNumber:) in conformance BinaryEncodingSizeVisitor at <compiler-generated>:0 [opt]
    frame #8: 0x000000010017e0fc PIRProcessDatabase`closure #1 in Apple_SwiftHomomorphicEncryption_V1_SerializedEvaluationKey.traverse<SwiftProtobuf.BinaryEncodingSizeVisitor>(, visitor=(serializedSize = 0)) at apple_swift_homomorphic_encryption_v1_he.pb.swift:800:19 [opt]
    frame #9: 0x000000010017e028 PIRProcessDatabase`Apple_SwiftHomomorphicEncryption_V1_SerializedEvaluationKey.traverse<SwiftProtobuf.BinaryEncodingSizeVisitor>(visitor=(serializedSize = 0)) at apple_swift_homomorphic_encryption_v1_he.pb.swift:799:9 [opt]
    frame #10: 0x000000010017e354 PIRProcessDatabase`protocol witness for Message.traverse<A>(visitor:) in conformance Apple_SwiftHomomorphicEncryption_V1_SerializedEvaluationKey at <compiler-generated>:0 [opt]
    frame #11: 0x000000010028c810 PIRProcessDatabase`Message.serializedBytes<HomomorphicEncryptionProtobuf.Apple_SwiftHomomorphicEncryption_V1_SerializedEvaluationKey>(partial:options:) at Message+BinaryAdditions.swift:74:9 [opt]
    frame #12: 0x000000010028c7e0 PIRProcessDatabase`Message.serializedBytes<HomomorphicEncryptionProtobuf.Apple_SwiftHomomorphicEncryption_V1_SerializedEvaluationKey>(partial=<unavailable>, options=(useDeterministicOrdering = false)) at Message+BinaryAdditions.swift:41:28 [opt]
    frame #13: 0x0000000100217b08 PIRProcessDatabase`EvaluationKey.size() [inlined] generic specialization <HomomorphicEncryptionProtobuf.Apple_SwiftHomomorphicEncryption_V1_SerializedEvaluationKey> of SwiftProtobuf.Message.serializedData(partial: Swift.Bool) throws -> Foundation.Data at <compiler-generated>:0 [opt]
    frame #14: 0x0000000100217ab8 PIRProcessDatabase`EvaluationKey.size() at ConversionPir.swift:230:33 [opt]
    frame #15: 0x00000001001a0fbc PIRProcessDatabase`merged generic specialization <HomomorphicEncryption.Bfv<Swift.UInt64>> of PrivateInformationRetrieval.ProcessKeywordDatabase.ShardValidationResult.description() throws -> Swift.String + 504
    frame #16: 0x000000010019d764 PIRProcessDatabase`specialized ProcessDatabase.process<A>(config=<unavailable>) at ProcessDatabase.swift:386:57 [opt]
    frame #17: 0x00000001001a2cd0 PIRProcessDatabase`ProcessDatabase.run() at ProcessDatabase.swift:419:17 [opt]
    frame #18: 0x00000001001a2f98 PIRProcessDatabase`protocol witness for ParsableCommand.run() in conformance ProcessDatabase at <compiler-generated>:0 [opt]
    frame #19: 0x00000001001da6c8 PIRProcessDatabase`specialized static ProcessDatabase.$main() [inlined] generic specialization <PIRProcessDatabase.ProcessDatabase> of static ArgumentParser.ParsableCommand.main(Swift.Optional<Swift.Array<Swift.String>>) -> () at <compiler-generated>:0 [opt]
    frame #20: 0x00000001001da67c PIRProcessDatabase`specialized static ProcessDatabase.$main() [inlined] generic specialization <PIRProcessDatabase.ProcessDatabase> of static ArgumentParser.ParsableCommand.main() -> () at <compiler-generated>:0 [opt]
    frame #21: 0x00000001001da67c PIRProcessDatabase`specialized static ProcessDatabase.$main() at <compiler-generated>:299:1 [opt]
    frame #22: 0x00000001001a3140 PIRProcessDatabase`PIRProcessDatabase_main [inlined] static PIRProcessDatabase.ProcessDatabase.$main() -> () at ProcessDatabase.swift:0 [opt]
    frame #23: 0x00000001001a313c PIRProcessDatabase`PIRProcessDatabase_main at ProcessDatabase.swift:0 [opt]
    frame #24: 0x00000001833bc274 dyld`start + 2840