Oops: general protection fault, probably for non-canonical address 0xdffffc0000000083: 0000 [#1] SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000418-0x000000000000041f] CPU: 0 UID: 0 PID: 15816 Comm: syz.3.2649 Not tainted 6.16.0-rc4-syzkaller-00049-gb4911fb0b060 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:ip_ignore_linkdown include/linux/inetdevice.h:270 [inline] RIP: 0010:fib_lookup_good_nhc+0x85/0x3d0 net/ipv4/fib_trie.c:1408 Code: 4c 89 24 24 48 89 d8 48 c1 e8 03 42 80 3c 28 00 74 08 48 89 df e8 4b c2 34 f8 41 bc 18 04 00 00 4c 03 23 4c 89 e0 48 c1 e8 03 <42> 80 3c 28 00 74 08 4c 89 e7 e8 2c c2 34 f8 4d 8b 24 24 e8 33 0c RSP: 0018:ffffc9000f3ef2b0 EFLAGS: 00010202 RAX: 0000000000000083 RBX: ffff88803399b020 RCX: 0000000000000002 RDX: ffff88803f610000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff88803399b037 R08: ffffc9000f3ef52f R09: 0000000000000000 R10: ffffc9000f3ef500 R11: fffff52001e7dea6 R12: 0000000000000418 R13: dffffc0000000000 R14: 0000000000000000 R15: 1ffff11006733606 FS: 00007f626e45e6c0(0000) GS:ffff888125c84000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000007d336000 CR4: 00000000003526f0 Call Trace: nexthop_get_nhc_lookup+0x1af/0x400 include/net/nexthop.h:437 fib_table_lookup+0xf26/0x16e0 net/ipv4/fib_trie.c:1584 __inet_dev_addr_type+0x2a2/0x4b0 net/ipv4/fib_frontend.c:225 rds_tcp_laddr_check+0x103/0x330 net/rds/tcp.c:326 rds_trans_get_preferred+0x23b/0x3c0 net/rds/transport.c:104 __rds_conn_create+0xa41/0x2060 net/rds/connection.c:239 rds_conn_create_outgoing+0x43/0x60 net/rds/connection.c:363 rds_sendmsg+0x1001/0x1f00 net/rds/send.c:1294 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg+0x21c/0x270 net/socket.c:727 ____sys_sendmsg+0x505/0x830 net/socket.c:2566 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2620 __sys_sendmsg net/socket.c:2652 [inline] __do_sys_sendmsg net/socket.c:2657 [inline] __se_sys_sendmsg net/socket.c:2655 [inline] __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2655 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f626d58e929 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f626e45e038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f626d7b6080 RCX: 00007f626d58e929 RDX: 0000000000000000 RSI: 0000200000000080 RDI: 000000000000000b RBP: 00007f626d610b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f626d7b6080 R15: 00007ffca0ccfc88 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:ip_ignore_linkdown include/linux/inetdevice.h:270 [inline] RIP: 0010:fib_lookup_good_nhc+0x85/0x3d0 net/ipv4/fib_trie.c:1408 Code: 4c 89 24 24 48 89 d8 48 c1 e8 03 42 80 3c 28 00 74 08 48 89 df e8 4b c2 34 f8 41 bc 18 04 00 00 4c 03 23 4c 89 e0 48 c1 e8 03 <42> 80 3c 28 00 74 08 4c 89 e7 e8 2c c2 34 f8 4d 8b 24 24 e8 33 0c RSP: 0018:ffffc9000f3ef2b0 EFLAGS: 00010202 RAX: 0000000000000083 RBX: ffff88803399b020 RCX: 0000000000000002 RDX: ffff88803f610000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff88803399b037 R08: ffffc9000f3ef52f R09: 0000000000000000 R10: ffffc9000f3ef500 R11: fffff52001e7dea6 R12: 0000000000000418 R13: dffffc0000000000 R14: 0000000000000000 R15: 1ffff11006733606 FS: 00007f626e45e6c0(0000) GS:ffff888125c84000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f99317b7bac CR3: 000000007d336000 CR4: 00000000003526f0 ---------------- Code disassembly (best guess): 0: 4c 89 24 24 mov %r12,(%rsp) 4: 48 89 d8 mov %rbx,%rax 7: 48 c1 e8 03 shr $0x3,%rax b: 42 80 3c 28 00 cmpb $0x0,(%rax,%r13,1) 10: 74 08 je 0x1a 12: 48 89 df mov %rbx,%rdi 15: e8 4b c2 34 f8 call 0xf834c265 1a: 41 bc 18 04 00 00 mov $0x418,%r12d 20: 4c 03 23 add (%rbx),%r12 23: 4c 89 e0 mov %r12,%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: 4c 89 e7 mov %r12,%rdi 34: e8 2c c2 34 f8 call 0xf834c265 39: 4d 8b 24 24 mov (%r12),%r12 3d: e8 .byte 0xe8 3e: 33 .byte 0x33 3f: 0c .byte 0xc