device syz_tun entered promiscuous mode device syz_tun left promiscuous mode bridge163: port 1(syz_tun) entered disabled state Disabling bearer ================================================================== BUG: KASAN: use-after-free in tipc_udp_xmit+0xa7d/0xc10 net/tipc/udp_media.c:200 Read of size 8 at addr ffff8880a1eada60 by task syz-executor.1/8077 CPU: 1 PID: 8077 Comm: syz-executor.1 Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/21/2023 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fc/0x2ef lib/dump_stack.c:118 print_address_description.cold+0x54/0x219 mm/kasan/report.c:256 kasan_report_error.cold+0x8a/0x1b9 mm/kasan/report.c:354 kasan_report mm/kasan/report.c:412 [inline] __asan_report_load8_noabort+0x88/0x90 mm/kasan/report.c:433 tipc_udp_xmit+0xa7d/0xc10 net/tipc/udp_media.c:200 tipc_udp_send_msg+0x279/0x490 net/tipc/udp_media.c:248 tipc_bearer_xmit_skb+0x15b/0x330 net/tipc/bearer.c:518 tipc_disc_timeout+0x855/0xc90 net/tipc/discover.c:332 call_timer_fn+0x177/0x700 kernel/time/timer.c:1338 expire_timers+0x243/0x4e0 kernel/time/timer.c:1375 __run_timers kernel/time/timer.c:1696 [inline] run_timer_softirq+0x21c/0x670 kernel/time/timer.c:1709 __do_softirq+0x265/0x980 kernel/softirq.c:292 invoke_softirq kernel/softirq.c:372 [inline] irq_exit+0x215/0x260 kernel/softirq.c:412 exiting_irq arch/x86/include/asm/apic.h:536 [inline] smp_apic_timer_interrupt+0x136/0x550 arch/x86/kernel/apic/apic.c:1098 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:894 RIP: 0010:__sanitizer_cov_trace_pc+0x37/0x50 kernel/kcov.c:106 Code: 65 8b 15 cc 59 9f 7e 81 e2 00 01 1f 00 75 2b 8b 90 60 13 00 00 83 fa 02 75 20 48 8b 88 68 13 00 00 8b 80 64 13 00 00 48 8b 11 <48> 83 c2 01 48 39 d0 76 07 48 89 34 d1 48 89 11 c3 0f 1f 84 00 00 RSP: 0018:ffff88802a21fa40 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: 0000000000040000 RBX: 0000000000000001 RCX: ffffc90008741000 RDX: 00000000000064b8 RSI: ffffffff81d86c30 RDI: 0000000000000001 RBP: ffff8880a394c980 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffff8880a394e9c0 R13: 0000000000000000 R14: ffff8880a394d000 R15: 0000000000000000 __read_once_size include/linux/compiler.h:263 [inline] ext4_get_group_desc+0x140/0x4e0 fs/ext4/balloc.c:284 recently_deleted fs/ext4/ialloc.c:680 [inline] find_inode_bit+0x1a0/0x520 fs/ext4/ialloc.c:724 __ext4_new_inode+0x160c/0x5a20 fs/ext4/ialloc.c:916 ext4_mkdir+0x396/0xe10 fs/ext4/namei.c:2696 vfs_mkdir+0x508/0x7a0 fs/namei.c:3819 do_mkdirat+0x262/0x2d0 fs/namei.c:3842 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f544f502117 Code: 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 02 01 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f544da74f88 EFLAGS: 00000246 ORIG_RAX: 0000000000000102 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f544f502117 RDX: 00000000000001ff RSI: 0000000020000440 RDI: 00000000ffffff9c RBP: 0000000020000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000020000440 R14: 00007f544da74fe0 R15: 0000000000000000 Allocated by task 8041: kmem_cache_alloc+0x122/0x370 mm/slab.c:3559 sock_alloc_inode+0x19/0x250 net/socket.c:244 alloc_inode+0x5d/0x180 fs/inode.c:211 new_inode_pseudo+0x14/0xe0 fs/inode.c:911 sock_alloc+0x3c/0x260 net/socket.c:567 __sock_create+0xba/0x740 net/socket.c:1329 udp_sock_create6+0xd1/0x550 net/ipv6/ip6_udp_tunnel.c:22 udp_sock_create include/net/udp_tunnel.h:61 [inline] tipc_udp_enable+0xb48/0x14d0 net/tipc/udp_media.c:734 tipc_enable_bearer+0x70f/0xbe0 net/tipc/bearer.c:317 __tipc_nl_bearer_enable+0x2e2/0x3d0 net/tipc/bearer.c:916 tipc_nl_bearer_enable+0x1e/0x30 net/tipc/bearer.c:925 genl_family_rcv_msg+0x642/0xc40 net/netlink/genetlink.c:602 genl_rcv_msg+0xbf/0x160 net/netlink/genetlink.c:627 netlink_rcv_skb+0x160/0x440 net/netlink/af_netlink.c:2463 genl_rcv+0x24/0x40 net/netlink/genetlink.c:638 netlink_unicast_kernel net/netlink/af_netlink.c:1325 [inline] netlink_unicast+0x4d5/0x690 net/netlink/af_netlink.c:1351 netlink_sendmsg+0x6c3/0xc50 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg+0xc3/0x120 net/socket.c:661 ___sys_sendmsg+0x7bb/0x8e0 net/socket.c:2227 __sys_sendmsg net/socket.c:2265 [inline] __do_sys_sendmsg net/socket.c:2274 [inline] __se_sys_sendmsg net/socket.c:2272 [inline] __x64_sys_sendmsg+0x132/0x220 net/socket.c:2272 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 2842: __cache_free mm/slab.c:3503 [inline] kmem_cache_free+0x7f/0x260 mm/slab.c:3765 destroy_inode+0xb9/0x110 fs/inode.c:268 iput_final fs/inode.c:1555 [inline] iput+0x4f1/0x860 fs/inode.c:1581 __sock_release net/socket.c:611 [inline] sock_release+0x174/0x1d0 net/socket.c:619 cleanup_bearer+0x1bb/0x280 net/tipc/udp_media.c:775 process_one_work+0x864/0x1570 kernel/workqueue.c:2153 worker_thread+0x64c/0x1130 kernel/workqueue.c:2296 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 The buggy address belongs to the object at ffff8880a1eada40 which belongs to the cache sock_inode_cache of size 992 The buggy address is located 32 bytes inside of 992-byte region [ffff8880a1eada40, ffff8880a1eade20) The buggy address belongs to the page: page:ffffea000287ab40 count:1 mapcount:0 mapping:ffff8880b5b8fc00 index:0xffff8880a1eadffd flags: 0xfff00000000100(slab) raw: 00fff00000000100 ffffea00023fca08 ffffea00024037c8 ffff8880b5b8fc00 raw: ffff8880a1eadffd ffff8880a1ead140 0000000100000003 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880a1ead900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880a1ead980: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc >ffff8880a1eada00: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb ^ ffff8880a1eada80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880a1eadb00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: 65 8b 15 cc 59 9f 7e mov %gs:0x7e9f59cc(%rip),%edx # 0x7e9f59d3 7: 81 e2 00 01 1f 00 and $0x1f0100,%edx d: 75 2b jne 0x3a f: 8b 90 60 13 00 00 mov 0x1360(%rax),%edx 15: 83 fa 02 cmp $0x2,%edx 18: 75 20 jne 0x3a 1a: 48 8b 88 68 13 00 00 mov 0x1368(%rax),%rcx 21: 8b 80 64 13 00 00 mov 0x1364(%rax),%eax 27: 48 8b 11 mov (%rcx),%rdx * 2a: 48 83 c2 01 add $0x1,%rdx <-- trapping instruction 2e: 48 39 d0 cmp %rdx,%rax 31: 76 07 jbe 0x3a 33: 48 89 34 d1 mov %rsi,(%rcx,%rdx,8) 37: 48 89 11 mov %rdx,(%rcx) 3a: c3 retq 3b: 0f .byte 0xf 3c: 1f (bad) 3d: 84 00 test %al,(%rax)