Issue Report: Runtime Error with slice bounds out of range in 0g-storage-client

[Josephtran102]

I encountered a runtime error when attempting to download a file using the 0g-storage-client with RPC endpoint STORAGE_RPC2 from VPS1. Here are the details:

1. Setup:
VPS 1 with RPC: STORAGE_RPC1="https://storage-node1.0gchain.josephtran.xyz/"
VPS 2 with RPC: STORAGE_RPC2="https://storage-node2.0gchain.josephtran.xyz/"

2. Run download:
On VPS 1, use the following command:

./0g-storage-client download --node $STORAGE_RPC2 --root 0xd5235f0ffe9c20d5eed863959ad7e7570437f6d6bb7a36b7a1574afe946457b4 --file /root/0g-storage-client/out3.test.txt

The following error occurs:

panic: runtime error: slice bounds out of range [:-243]

goroutine 16 [running]:
github.com/0glabs/0g-storage-client/transfer.(*SegmentDownloader).ParallelDo(0xc000521740, 0xc000521708, 0x0)
        /root/0g-storage-client/transfer/download_parallel.go:107 +0x905
github.com/0glabs/0g-storage-client/common/parallel.work({0xdfe300, 0xc0003f1860}, 0x0, {0xdfac20, 0xc000512f00}, 0xc0002659d0, 0xc000512f60, 0xc00036e2f1)
        /root/0g-storage-client/common/parallel/serial.go:59 +0x131
created by github.com/0glabs/0g-storage-client/common/parallel.Serial in goroutine 1
        /root/0g-storage-client/common/parallel/serial.go:37 +0x1bf

3. Additional Information:
Using RPC endpoint STORAGE_RPC1 on VPS 1 works as expected without any errors.

RPC endpoint STORAGE_RPC2 has been tested independently using curl and download function correctly.

root@vmi1810073:~/0g-storage-client# curl -X POST $STORAGE_RPC2 -H "Content-Type: application/json" -d '{"jsonrpc":"2.0","method":"zgs_getStatus","params":[],"id":1}'  | jq
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100   223  100   162  100    61    197     74 --:--:-- --:--:-- --:--:--   274

Result:

{
  "jsonrpc": "2.0",
  "result": {
    "connectedPeers": 46,
    "logSyncHeight": 125836,
    "logSyncBlock": "0x8a528b56863e30c50333c23dea5db82e91bee2f2ed1028d5945669cedd364809"
  },
  "id": 1
}

4. Further Testing:
I tested using STORAGE_RPC1 on VPS 2 and encountered no issues. The file downloaded successfully without errors.

*Environment:

Operating System: Linux (Ubuntu 22.04.4 LTS)
Go version: go1.22.0 linux/amd64

This issue seems to be specific to how 0g-storage-client interacts with data from RPC endpoint STORAGE_RPC2 on VPS 1. Please investigate and provide guidance on resolving this issue.

[MiniFrenchBread]

Hi @Josephtran102 , Thanks for reporting this!

The data you are querying for is missing on the storage node behind STORAGE_RPC2, meanwhile the client did not handle the returned empty data properly. This issue will be fixed in an upcoming PR.

[MiniFrenchBread]

added checks for downloaded data in #16

[Josephtran102]

Thanks @MiniFrenchBread