Re: [PATCH bpf-next v2 3/4] bpf: add bpf_icmp_send_unreach cgroup_skb kfunc

[kernel test robot <lkp@intel.com>]

Hi Mahe,

kernel test robot noticed the following build errors:

[auto build test ERROR on bpf-next/master]

url:    https://github.com/intel-lab-lkp/linux/commits/Mahe-Tardy/net-move-netfilter-nf_reject_fill_skb_dst-to-core-ipv4/20250726-030109
base:   https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git master
patch link:    https://lore.kernel.org/r/20250725185342.262067-4-mahe.tardy%40gmail.com
patch subject: [PATCH bpf-next v2 3/4] bpf: add bpf_icmp_send_unreach cgroup_skb kfunc
config: arm64-defconfig (https://download.01.org/0day-ci/archive/20250727/202507270940.kXGmRbg5-lkp@intel.com/config)
compiler: aarch64-linux-gcc (GCC) 15.1.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250727/202507270940.kXGmRbg5-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202507270940.kXGmRbg5-lkp@intel.com/

All errors (new ones prefixed by >>):

   aarch64-linux-ld: Unexpected GOT/PLT entries detected!
   aarch64-linux-ld: Unexpected run-time procedure linkages detected!
   aarch64-linux-ld: net/core/filter.o: in function `bpf_icmp_send_unreach':
>> net/core/filter.c:12184:(.text+0x14574): undefined reference to `ip6_route_reply_fetch_dst'


vim +12184 net/core/filter.c

 12152	
 12153	__bpf_kfunc int bpf_icmp_send_unreach(struct __sk_buff *__skb, int code)
 12154	{
 12155		struct sk_buff *skb = (struct sk_buff *)__skb;
 12156		struct sk_buff *nskb;
 12157	
 12158		switch (skb->protocol) {
 12159		case htons(ETH_P_IP):
 12160			if (code < 0 || code > NR_ICMP_UNREACH)
 12161				return -EINVAL;
 12162	
 12163			nskb = skb_clone(skb, GFP_ATOMIC);
 12164			if (!nskb)
 12165				return -ENOMEM;
 12166	
 12167			if (ip_route_reply_fetch_dst(nskb) < 0) {
 12168				kfree_skb(nskb);
 12169				return -EHOSTUNREACH;
 12170			}
 12171	
 12172			icmp_send(nskb, ICMP_DEST_UNREACH, code, 0);
 12173			kfree_skb(nskb);
 12174			break;
 12175	#if IS_ENABLED(CONFIG_IPV6)
 12176		case htons(ETH_P_IPV6):
 12177			if (code < 0 || code > ICMPV6_REJECT_ROUTE)
 12178				return -EINVAL;
 12179	
 12180			nskb = skb_clone(skb, GFP_ATOMIC);
 12181			if (!nskb)
 12182				return -ENOMEM;
 12183	
 12184			if (ip6_route_reply_fetch_dst(nskb) < 0) {
 12185				kfree_skb(nskb);
 12186				return -EHOSTUNREACH;
 12187			}
 12188	
 12189			icmpv6_send(nskb, ICMPV6_DEST_UNREACH, code, 0);
 12190			kfree_skb(nskb);
 12191			break;
 12192	#endif
 12193		default:
 12194			return -EPROTONOSUPPORT;
 12195		}
 12196	
 12197		return SK_DROP;
 12198	}
 12199	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki