Enabled bearer , priority 10 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 ffff88806ca62160 by task syz-executor.4/17557 CPU: 0 PID: 17557 Comm: syz-executor.4 Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 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:__read_once_size include/linux/compiler.h:263 [inline] RIP: 0010:unlocked_inode_to_wb_begin include/linux/backing-dev.h:372 [inline] RIP: 0010:clear_page_dirty_for_io+0x3a1/0xee0 mm/page-writeback.c:2697 Code: 00 00 e8 32 98 e2 ff 49 8d bc 24 d0 00 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 04 0a 00 00 <49> 8b 9c 24 d0 00 00 00 81 e3 00 20 00 00 31 ff 48 89 de e8 87 99 RSP: 0018:ffff888069e3f518 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: dffffc0000000000 RBX: 0000000000000001 RCX: ffffc90009a43000 RDX: 1ffff1100d0cde70 RSI: ffffffff817fed3e RDI: ffff88806866f380 RBP: ffffea0001da5800 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 000000008075da1b R12: ffff88806866f2b0 R13: ffffea0001da5808 R14: ffff8880a3dc4bc0 R15: ffffea000223a208 mpage_submit_page+0x80/0x250 fs/ext4/inode.c:2215 mpage_map_and_submit_buffers fs/ext4/inode.c:2431 [inline] mpage_map_and_submit_extent fs/ext4/inode.c:2569 [inline] ext4_writepages+0x20fc/0x37f0 fs/ext4/inode.c:2882 do_writepages+0xe5/0x290 mm/page-writeback.c:2344 __filemap_fdatawrite_range+0x27d/0x350 mm/filemap.c:446 filemap_write_and_wait_range mm/filemap.c:679 [inline] filemap_write_and_wait_range+0x46/0xd0 mm/filemap.c:673 generic_file_direct_write+0x389/0x4a0 mm/filemap.c:3049 __generic_file_write_iter+0x2d0/0x610 mm/filemap.c:3252 ext4_file_write_iter+0x2fe/0xf20 fs/ext4/file.c:272 call_write_iter include/linux/fs.h:1821 [inline] new_sync_write fs/read_write.c:474 [inline] __vfs_write+0x51b/0x770 fs/read_write.c:487 vfs_write+0x1f3/0x540 fs/read_write.c:549 ksys_write+0x12b/0x2a0 fs/read_write.c:599 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f4bb1e660e9 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f4bb07db168 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f4bb1f78f60 RCX: 00007f4bb1e660e9 RDX: 0000000000023000 RSI: 0000000020000200 RDI: 0000000000000005 RBP: 00007f4bb1ec008d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fff50f5ff4f R14: 00007f4bb07db300 R15: 0000000000022000 Allocated by task 17552: 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 3462: __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 ffff88806ca62140 which belongs to the cache sock_inode_cache of size 992 The buggy address is located 32 bytes inside of 992-byte region [ffff88806ca62140, ffff88806ca62520) The buggy address belongs to the page: page:ffffea0001b29880 count:1 mapcount:0 mapping:ffff8880b5b96780 index:0xffff88806ca62ffd flags: 0xfff00000000100(slab) raw: 00fff00000000100 ffffea0001b29fc8 ffffea0001b29848 ffff8880b5b96780 raw: ffff88806ca62ffd ffff88806ca62140 0000000100000003 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88806ca62000: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88806ca62080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88806ca62100: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb ^ ffff88806ca62180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88806ca62200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: 00 00 add %al,(%rax) 2: e8 32 98 e2 ff callq 0xffe29839 7: 49 8d bc 24 d0 00 00 lea 0xd0(%r12),%rdi e: 00 f: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 16: fc ff df 19: 48 89 fa mov %rdi,%rdx 1c: 48 c1 ea 03 shr $0x3,%rdx 20: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) 24: 0f 85 04 0a 00 00 jne 0xa2e * 2a: 49 8b 9c 24 d0 00 00 mov 0xd0(%r12),%rbx <-- trapping instruction 31: 00 32: 81 e3 00 20 00 00 and $0x2000,%ebx 38: 31 ff xor %edi,%edi 3a: 48 89 de mov %rbx,%rsi 3d: e8 .byte 0xe8 3e: 87 .byte 0x87 3f: 99 cltd