bonding: provide a net pointer to __skb_flow_dissect()

bonding: provide a net pointer to __skb_flow_dissect()

After 3cbf4ffba5ee ("net: plumb network namespace into __skb_flow_dissect")
we have to provide a net pointer to __skb_flow_dissect(),
either via skb->dev, skb->sk, or a user provided pointer.

In the following case, syzbot was able to cook a bare skb.

WARNING: net/core/flow_dissector.c:1131 at __skb_flow_dissect+0xb57/0x68b0 net/core/flow_dissector.c:1131, CPU#1: syz.2.1418/11053
Call Trace:
 <TASK>
  bond_flow_dissect drivers/net/bonding/bond_main.c:4093 [inline]
  __bond_xmit_hash+0x2d7/0xba0 drivers/net/bonding/bond_main.c:4157
  bond_xmit_hash_xdp drivers/net/bonding/bond_main.c:4208 [inline]
  bond_xdp_xmit_3ad_xor_slave_get drivers/net/bonding/bond_main.c:5139 [inline]
  bond_xdp_get_xmit_slave+0x1fd/0x710 drivers/net/bonding/bond_main.c:5515
  xdp_master_redirect+0x13f/0x2c0 net/core/filter.c:4388
  bpf_prog_run_xdp include/net/xdp.h:700 [inline]
  bpf_test_run+0x6b2/0x7d0 net/bpf/test_run.c:421
  bpf_prog_test_run_xdp+0x795/0x10e0 net/bpf/test_run.c:1390
  bpf_prog_test_run+0x2c7/0x340 kernel/bpf/syscall.c:4703
  __sys_bpf+0x562/0x860 kernel/bpf/syscall.c:6182
  __do_sys_bpf kernel/bpf/syscall.c:6274 [inline]
  __se_sys_bpf kernel/bpf/syscall.c:6272 [inline]
  __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:6272
  do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
  do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94

Fixes: 58deb77cc52d ("bonding: balance ICMP echoes in layer3+4 mode")
Reported-by: syzbot+c46409299c70a221415e@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/netdev/696faa23.050a0220.4cb9c.001f.GAE@google.com/T/#u
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Matteo Croce <mcroce@redhat.com>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20260120161744.1893263-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>