lwIP: constrain ping address resolution to IPv4

[Old-Ding]

Summary

• constrain custom lwIP ping address resolution to IPv4 in all three bundled lwIP versions
• replace pointer memcpy with direct struct sockaddr_in * assignment in the same code path
• fix malformed #endif comments next to the touched code

Root Cause

The custom ping implementation creates an IPv4 raw ICMP socket, but its lwip_getaddrinfo() hint did not explicitly request IPv4 addresses. On dual-stack configurations, address resolution may return an address family that does not match the later IPv4 ICMP path.

Details

The fix sets hint.ai_family = AF_INET immediately after initializing the addrinfo hint. This keeps the responsibility at the address resolution layer and does not add duplicate checks later in the ping flow.

This intentionally does not change netdev ping behavior, does not add IPv6 ping support, and does not restructure the ping command.

Validation

• git diff --check origin/master..HEAD
• rg -n "#endif\\s+/\\s+\\*" components/net/lwip
• rg -n "memcpy\\(&h,\\s*&res->ai_addr|rt_memcpy\\(&h,\\s*&res->ai_addr" components/net/lwip
• tools/ci/file_check.py FormatCheck for the three touched ping.c files

Local BSP build was not run because this Windows environment does not have scons, gcc, arm-none-eabi-gcc, or MSVC cl available.

[github-actions]

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[github-actions]

📌 Code Review Assignment

🏷️ Tag: components

Reviewers: Maihuanyi

Changed Files (Click to expand)

• components/net/lwip/lwip-1.4.1/src/apps/ping/ping.c
• components/net/lwip/lwip-2.0.3/src/apps/ping/ping.c
• components/net/lwip/lwip-2.1.2/src/apps/ping/ping.c
• components/net/lwip/port/ethernetif.c

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📊 Current Review Status (Last Updated: 2026-06-29 11:06 CST)

• ⌛ Maihuanyi Pending Review

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[github-actions]

MemBrowse Memory Report

loongson-ls1cdev

• Code: .text -8 B (-0.0%, 362,496 B)
  No memory changes detected for:
• at32f415-start
• esp32-c3
• gd32105r-start
• hc32f334
• hpmicro-hpm5301evklite
• infineon-psoc6
• k230
• nordic-nrf51822
• nuvoton-m487
• nxp-lpc1114
• qemu-virt64-aarch64
• raspberry-pico-rp2040
• renesas-ra2l1
• simulator
• stm32f407-rt-spark
• stm32l475-atk-pandora-llvm
• wch-ch32v208w-r0
• x86
• xuantie-e901plus

[Rbb666]

https://github.com/RT-Thread/rt-thread/blob/master/components/net/lwip/port/ethernetif.c#L240

Does this part have the same problem?

[Old-Ding]

Good catch, this path has the same IPv4 raw ICMP assumption. I updated lwip_netdev_ping() to constrain getaddrinfo() to AF_INET and replaced the pointer SMEMCPY with a direct sockaddr_in * assignment as well.