batman_adv: batadv0: The MTU of interface batadv_slave_1 is too small (1500) to handle the transport of batman-adv packets. Packets going over this interface will be fragmented on layer2 which could impact the performance. Setting the MTU to 1560 would solve the problem. batman_adv: batadv0: Not using interface batadv_slave_1 (retrying later): interface not active Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] CPU: 0 UID: 0 PID: 5426 Comm: syz-executor Not tainted 6.11.0-rc4-next-20240822-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 RIP: 0010:rb_set_parent include/linux/rbtree_augmented.h:185 [inline] RIP: 0010:__rb_erase_augmented include/linux/rbtree_augmented.h:305 [inline] RIP: 0010:rb_erase+0x345/0xe70 lib/rbtree.c:443 Code: cb 44 f6 49 8b 2f 4c 8d 73 10 4c 89 f0 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89 f7 e8 e5 cb 44 f6 49 89 2e 48 89 e8 48 c1 e8 03 <42> 80 3c 28 00 74 08 48 89 ef e8 dc ca 44 f6 4c 89 24 24 48 8b 45 RSP: 0018:ffffc900044a6540 EFLAGS: 00010046 RAX: 0000000000000000 RBX: ffff888021875cc0 RCX: dffffc0000000000 RDX: dffffc0000000000 RSI: ffff8880b913f860 RDI: ffff88801ab2bec8 RBP: 0000000000000000 R08: ffff88801ab2c037 R09: 1ffff11003565806 R10: dffffc0000000000 R11: ffffed1003565807 R12: ffff88801ab2bec0 R13: dffffc0000000000 R14: ffff888021875cd0 R15: ffff88801ab2bed0 FS: 000055555c119500(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc442317a8c CR3: 0000000023e04000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: sched_core_dequeue kernel/sched/core.c:283 [inline] dequeue_task+0x34d/0x550 kernel/sched/core.c:2031 detach_task kernel/sched/fair.c:9368 [inline] detach_tasks kernel/sched/fair.c:9504 [inline] sched_balance_rq+0x5d5b/0x8590 kernel/sched/fair.c:11648 sched_balance_newidle+0x6ba/0xfd0 kernel/sched/fair.c:12703 balance_fair+0x44/0x70 kernel/sched/fair.c:8620 put_prev_task_balance kernel/sched/core.c:5923 [inline] pick_next_task kernel/sched/core.c:6092 [inline] __schedule+0x2b16/0x4b30 kernel/sched/core.c:6632 __schedule_loop kernel/sched/core.c:6754 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6769 synchronize_rcu_expedited+0x684/0x830 kernel/rcu/tree_exp.h:991 synchronize_rcu+0x11b/0x360 kernel/rcu/tree.c:4094 hsr_add_port+0x437/0x790 net/hsr/hsr_slave.c:198 hsr_dev_finalize+0x45f/0x970 net/hsr/hsr_device.c:643 hsr_newlink+0x7ee/0x970 net/hsr/hsr_netlink.c:123 rtnl_newlink_create net/core/rtnetlink.c:3510 [inline] __rtnl_newlink net/core/rtnetlink.c:3730 [inline] rtnl_newlink+0x1591/0x20a0 net/core/rtnetlink.c:3743 rtnetlink_rcv_msg+0x73f/0xcf0 net/core/rtnetlink.c:6647 netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2550 netlink_unicast_kernel net/netlink/af_netlink.c:1331 [inline] netlink_unicast+0x7f6/0x990 net/netlink/af_netlink.c:1357 netlink_sendmsg+0x8e4/0xcb0 net/netlink/af_netlink.c:1901 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:745 __sys_sendto+0x3a8/0x500 net/socket.c:2204 __do_sys_sendto net/socket.c:2216 [inline] __se_sys_sendto net/socket.c:2212 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2212 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f98a177bd0c Code: 2a 5a 02 00 44 8b 4c 24 2c 4c 8b 44 24 20 89 c5 44 8b 54 24 28 48 8b 54 24 18 b8 2c 00 00 00 48 8b 74 24 10 8b 7c 24 08 0f 05 <48> 3d 00 f0 ff ff 77 34 89 ef 48 89 44 24 08 e8 70 5a 02 00 48 8b RSP: 002b:00007ffdc6033870 EFLAGS: 00000293 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007f98a2444620 RCX: 00007f98a177bd0c RDX: 0000000000000048 RSI: 00007f98a2444670 RDI: 0000000000000003 RBP: 0000000000000000 R08: 00007ffdc60338c4 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003 R13: 0000000000000000 R14: 00007f98a2444670 R15: 0000000000000000 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:rb_set_parent include/linux/rbtree_augmented.h:185 [inline] RIP: 0010:__rb_erase_augmented include/linux/rbtree_augmented.h:305 [inline] RIP: 0010:rb_erase+0x345/0xe70 lib/rbtree.c:443 Code: cb 44 f6 49 8b 2f 4c 8d 73 10 4c 89 f0 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89 f7 e8 e5 cb 44 f6 49 89 2e 48 89 e8 48 c1 e8 03 <42> 80 3c 28 00 74 08 48 89 ef e8 dc ca 44 f6 4c 89 24 24 48 8b 45 RSP: 0018:ffffc900044a6540 EFLAGS: 00010046 RAX: 0000000000000000 RBX: ffff888021875cc0 RCX: dffffc0000000000 RDX: dffffc0000000000 RSI: ffff8880b913f860 RDI: ffff88801ab2bec8 RBP: 0000000000000000 R08: ffff88801ab2c037 R09: 1ffff11003565806 R10: dffffc0000000000 R11: ffffed1003565807 R12: ffff88801ab2bec0 R13: dffffc0000000000 R14: ffff888021875cd0 R15: ffff88801ab2bed0 FS: 000055555c119500(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc442317a8c CR3: 0000000023e04000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: cb lret 1: 44 f6 49 8b 2f rex.R testb $0x2f,-0x75(%rcx) 6: 4c 8d 73 10 lea 0x10(%rbx),%r14 a: 4c 89 f0 mov %r14,%rax d: 48 c1 e8 03 shr $0x3,%rax 11: 42 80 3c 28 00 cmpb $0x0,(%rax,%r13,1) 16: 74 08 je 0x20 18: 4c 89 f7 mov %r14,%rdi 1b: e8 e5 cb 44 f6 call 0xf644cc05 20: 49 89 2e mov %rbp,(%r14) 23: 48 89 e8 mov %rbp,%rax 26: 48 c1 e8 03 shr $0x3,%rax * 2a: 42 80 3c 28 00 cmpb $0x0,(%rax,%r13,1) <-- trapping instruction 2f: 74 08 je 0x39 31: 48 89 ef mov %rbp,%rdi 34: e8 dc ca 44 f6 call 0xf644cb15 39: 4c 89 24 24 mov %r12,(%rsp) 3d: 48 rex.W 3e: 8b .byte 0x8b 3f: 45 rex.RB