Possible to add corrupted data to DB which crash the server when trying to query it

[felixfbecker]

If you suspect this could be a bug, follow the template.

• What version of Dgraph are you using?

Dgraph version : v1.0.16
Commit SHA-1 : 0590ee9
Commit timestamp : 2019-07-11 11:52:54 -0700
Branch : HEAD
Go version : go1.12.5

• Have you tried reproducing the issue with latest release?

should be latest

• What is the hardware spec (RAM, OS)?

macOS

• Steps to reproduce the issue (command/config used to run Dgraph).

I tried to figure out how to use the geo type. The API takes either a Base64 string or a UInt8Array. I wasn't sure how to encode coordinate in that, so I tried

value.setGeoVal(Buffer.from(JSON.stringify({ type: 'Point', coordinates: [0, 1] }).toString('base64'))

The mutation succeeded, but when I then queried for the UID, the server crashed with

2019/07/31 16:12:59 Error while interpreting appropriate type from binary error: wkb: unknown byte order: 1111011

• Expected behaviour and actual result.

This seems like it should not happen, the server should validate data before inserting so that corrupted data cannot crash the server.

[campoy]

Hi @felixfbecker,

Thanks for the report! Can you reproduce the issue on v1.1.0?

[campoy]

In the meantime, could you have a look @prashant-shahi?
Also, could you confirm whether this is a dgraph-js issue or something that could happen in other clients / curl?

[prashant-shahi]

@campoy I had looked into the issue and was able to reproduce it in v1.0.x, v1.1.0, and master with the dgraph-js. Even when a valid geojson is passed to Value#setGeoVal, this issue can be seen. Here is the complete code to reproduce the issue.
I wasn't able to reproduce the steps using the pydgraph.

When I used @index(geo) for the predicate in the schema, during the mutation itself, we get to see the error that used to crash the server while querying.

Nevertheless, we can make use of Mutation#setSetJson or Mutation#setSetNquads to perform the mutation and later query back successfully.

@danielmai and I discussed the same.

[mangalaman93]

I am able to reproduce this issue using Go code. Looking into it to figure out what is going on.