Panic in eth_callMany RPC method due to nil pointer dereference

[harshsingh-cs]

System information

Erigon version: erigon version 1.4.3-dev-b00927fe

OS & Version: Linux/

Commit hash: b00927fe

Erigon Command (with flags/config):

- erigon
        - --chain=bsc
        - --datadir=/home/erigon/persistence/data
        - --http.addr=0.0.0.0
        - --rpc.accessList=/home/erigon/acl-config/acl.json
        - --rpc.batch.limit=1000
        - --rpc.txfeecap=100
        - --http.api=eth,erigon,web3,net,debug,txpool,trace
        - --http.vhosts=*
        - --http.corsdomain=null
        - --http
        - --ws
        - --db.pagesize=16384
        - --ethash.dagdir=/home/erigon/persistence/dag
        - --maxpeers=32
        - --identity=nd-786-726-458
        - --private.api.addr=0.0.0.0:9090
        - --private.api.ratelimit=31872
        - --rpc.returndata.limit=1100000
        - --metrics
        - --metrics.addr=0.0.0.0
        - --healthcheck
        - --port=30303
        - --db.size.limit=5TB
        - --p2p.protocol=67,68
        - --rpc.batch.limit=1000
        - --rpc.returndata.limit=1100000
        - --http.timeouts.read=300s
        - --bsc.blobSidecars.no-pruning=true
        - --prune.mode=archive
        - --no-downloader
        - --bootnodes=...
        - --staticpeers=...
        image: ghcr.io/node-real/bsc-erigon:v1.4.3

Chain/Network: BSC Mainnet

Expected behaviour

Return a proper error message when the block cannot be found

Actual behaviour

Panic occurs because block is nil

The eth_callMany RPC method crashes with a nil pointer dereference panic when attempting to call on a block that doesn't exist.

Error Log

[EROR] [12-27|11:42:03.803] RPC method eth_callMany crashed: runtime error: invalid memory address or nil pointer dereference
[service.go:222 panic.go:792 panic.go:262 signal_unix.go:925 block.go:1327 eth_callMany.go:144 value.go:584 value.go:368 service.go:227 handler.go:529 handler.go:479 handler.go:420 handler.go:240 handler.go:333 asm_amd64.s:1700]

Likely Root Cause

In rpc/jsonrpc/eth_callMany.go, the api.blockWithSenders() method can return a nil block without returning an error when the requested block is not found. The code only checks for errors but doesn't validate that the block pointer is non-nil before attempting to access it

Problematic code (lines 130-144):

block, err := api.blockWithSenders(ctx, tx, hash, blockNum)
if err != nil {
    return nil, err
}
// Missing nil check here!
if transactionIndex == -1 {
    transactionIndex = len(block.Transactions()) // Panic occurs here
}

When block.Transactions() is called on a nil pointer, it triggers a panic in execution/types/block.go:1327

Impact

RPC service crashes instead of returning a proper error response
Affects any customer calling eth_callMany with a non-existent block number

Proposed Fix

Add a nil check after retrieving the block:

block, err := api.blockWithSenders(ctx, tx, hash, blockNum)
if err != nil {
    return nil, err
}
if block == nil {
    return nil, fmt.Errorf("block not found for number %d", blockNum)
}