sshd (5977) used greatest stack depth: 15744 bytes left Started in network mode Own node identity 00000000000000000000000000000001, cluster identity 4711 New replicast peer: fe80:0000:0000:0000:0000:0000:0000:00aa ================================================================== BUG: KASAN: use-after-free in atomic_read include/asm-generic/atomic-instrumented.h:21 [inline] BUG: KASAN: use-after-free in refcount_read include/linux/refcount.h:43 [inline] BUG: KASAN: use-after-free in skb_unref include/linux/skbuff.h:969 [inline] BUG: KASAN: use-after-free in kfree_skb+0xb7/0x580 net/core/skbuff.c:655 Read of size 4 at addr ffff8881bd1712a4 by task syz-executor529/5993 CPU: 1 PID: 5993 Comm: syz-executor529 Not tainted 4.20.0-rc6+ #370 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+0x244/0x39d lib/dump_stack.c:113 print_address_description.cold.7+0x9/0x1ff mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.8+0x242/0x309 mm/kasan/report.c:412 check_memory_region_inline mm/kasan/kasan.c:260 [inline] check_memory_region+0x13e/0x1b0 mm/kasan/kasan.c:267 kasan_check_read+0x11/0x20 mm/kasan/kasan.c:272 atomic_read include/asm-generic/atomic-instrumented.h:21 [inline] refcount_read include/linux/refcount.h:43 [inline] skb_unref include/linux/skbuff.h:969 [inline] kfree_skb+0xb7/0x580 net/core/skbuff.c:655 tipc_udp_send_msg+0x5a6/0x670 net/tipc/udp_media.c:249 tipc_bearer_xmit_skb+0x171/0x350 net/tipc/bearer.c:502 tipc_enable_bearer+0xc5e/0xf10 net/tipc/bearer.c:327 __tipc_nl_bearer_enable+0x37c/0x4a0 net/tipc/bearer.c:897 tipc_nl_bearer_enable+0x22/0x30 net/tipc/bearer.c:905 genl_family_rcv_msg+0x8a7/0x11a0 net/netlink/genetlink.c:601 genl_rcv_msg+0xc6/0x168 net/netlink/genetlink.c:626 netlink_rcv_skb+0x172/0x440 net/netlink/af_netlink.c:2477 genl_rcv+0x28/0x40 net/netlink/genetlink.c:637 netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline] netlink_unicast+0x5a5/0x760 net/netlink/af_netlink.c:1336 netlink_sendmsg+0xa18/0xfc0 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg+0xd5/0x120 net/socket.c:631 ___sys_sendmsg+0x7fd/0x930 net/socket.c:2116 __sys_sendmsg+0x11d/0x280 net/socket.c:2154 __do_sys_sendmsg net/socket.c:2163 [inline] __se_sys_sendmsg net/socket.c:2161 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2161 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4446f9 Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 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 0f 83 1b d8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffde52c0e58 EFLAGS: 00000213 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00000000004002e0 RCX: 00000000004446f9 RDX: 0000000000000000 RSI: 0000000020000700 RDI: 0000000000000003 RBP: 00000000006cf018 R08: 0000000000000000 R09: 00000000004002e0 R10: 0000000000000000 R11: 0000000000000213 R12: 00000000004023a0 R13: 0000000000402430 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 5993: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0xc7/0xe0 mm/kasan/kasan.c:553 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:490 kmem_cache_alloc_node+0x144/0x730 mm/slab.c:3644 __alloc_skb+0x119/0x770 net/core/skbuff.c:193 __pskb_copy_fclone+0x16b/0xeb0 net/core/skbuff.c:1385 __pskb_copy include/linux/skbuff.h:1053 [inline] pskb_copy include/linux/skbuff.h:2915 [inline] tipc_udp_send_msg+0x44e/0x670 net/tipc/udp_media.c:241 tipc_bearer_xmit_skb+0x171/0x350 net/tipc/bearer.c:502 tipc_enable_bearer+0xc5e/0xf10 net/tipc/bearer.c:327 __tipc_nl_bearer_enable+0x37c/0x4a0 net/tipc/bearer.c:897 tipc_nl_bearer_enable+0x22/0x30 net/tipc/bearer.c:905 genl_family_rcv_msg+0x8a7/0x11a0 net/netlink/genetlink.c:601 genl_rcv_msg+0xc6/0x168 net/netlink/genetlink.c:626 netlink_rcv_skb+0x172/0x440 net/netlink/af_netlink.c:2477 genl_rcv+0x28/0x40 net/netlink/genetlink.c:637 netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline] netlink_unicast+0x5a5/0x760 net/netlink/af_netlink.c:1336 netlink_sendmsg+0xa18/0xfc0 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg+0xd5/0x120 net/socket.c:631 ___sys_sendmsg+0x7fd/0x930 net/socket.c:2116 __sys_sendmsg+0x11d/0x280 net/socket.c:2154 __do_sys_sendmsg net/socket.c:2163 [inline] __se_sys_sendmsg net/socket.c:2161 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2161 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 5993: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/kasan.c:521 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 __cache_free mm/slab.c:3498 [inline] kmem_cache_free+0x83/0x290 mm/slab.c:3760 kfree_skbmem+0x154/0x230 net/core/skbuff.c:582 __kfree_skb net/core/skbuff.c:642 [inline] kfree_skb+0x1c3/0x580 net/core/skbuff.c:659 tipc_udp_xmit.isra.14+0x420/0xef0 net/tipc/udp_media.c:207 tipc_udp_send_msg+0x398/0x670 net/tipc/udp_media.c:247 tipc_bearer_xmit_skb+0x171/0x350 net/tipc/bearer.c:502 tipc_enable_bearer+0xc5e/0xf10 net/tipc/bearer.c:327 __tipc_nl_bearer_enable+0x37c/0x4a0 net/tipc/bearer.c:897 tipc_nl_bearer_enable+0x22/0x30 net/tipc/bearer.c:905 genl_family_rcv_msg+0x8a7/0x11a0 net/netlink/genetlink.c:601 genl_rcv_msg+0xc6/0x168 net/netlink/genetlink.c:626 netlink_rcv_skb+0x172/0x440 net/netlink/af_netlink.c:2477 genl_rcv+0x28/0x40 net/netlink/genetlink.c:637 netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline] netlink_unicast+0x5a5/0x760 net/netlink/af_netlink.c:1336 netlink_sendmsg+0xa18/0xfc0 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg+0xd5/0x120 net/socket.c:631 ___sys_sendmsg+0x7fd/0x930 net/socket.c:2116 __sys_sendmsg+0x11d/0x280 net/socket.c:2154 __do_sys_sendmsg net/socket.c:2163 [inline] __se_sys_sendmsg net/socket.c:2161 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2161 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff8881bd1711c0 which belongs to the cache skbuff_head_cache of size 232 The buggy address is located 228 bytes inside of 232-byte region [ffff8881bd1711c0, ffff8881bd1712a8) The buggy address belongs to the page: page:ffffea0006f45c40 count:1 mapcount:0 mapping:ffff8881d9a1c0c0 index:0x0 flags: 0x2fffc0000000200(slab) raw: 02fffc0000000200 ffffea0006f2a4c8 ffffea0006f2fec8 ffff8881d9a1c0c0 raw: 0000000000000000 ffff8881bd171080 000000010000000c 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8881bd171180: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb ffff8881bd171200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8881bd171280: fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc ^ ffff8881bd171300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881bd171380: fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc ================================================================== ================================================================== BUG: KASAN: double-free or invalid-free in skb_free_head+0x99/0xc0 net/core/skbuff.c:550 CPU: 1 PID: 5993 Comm: syz-executor529 Tainted: G B 4.20.0-rc6+ #370 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+0x244/0x39d lib/dump_stack.c:113 print_address_description.cold.7+0x9/0x1ff mm/kasan/report.c:256 kasan_report_invalid_free+0x64/0xa0 mm/kasan/report.c:336 __kasan_slab_free+0x13a/0x150 mm/kasan/kasan.c:501 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 __cache_free mm/slab.c:3498 [inline] kfree+0xcf/0x230 mm/slab.c:3817 skb_free_head+0x99/0xc0 net/core/skbuff.c:550 skb_release_data+0x70c/0x9a0 net/core/skbuff.c:570 skb_release_all+0x4a/0x60 net/core/skbuff.c:627 __kfree_skb net/core/skbuff.c:641 [inline] kfree_skb+0x1bb/0x580 net/core/skbuff.c:659 tipc_udp_send_msg+0x5a6/0x670 net/tipc/udp_media.c:249 tipc_bearer_xmit_skb+0x171/0x350 net/tipc/bearer.c:502 tipc_disc_timeout+0xb2b/0xfc0 net/tipc/discover.c:332 call_timer_fn+0x272/0x920 kernel/time/timer.c:1326 expire_timers kernel/time/timer.c:1363 [inline] __run_timers+0x7e5/0xc70 kernel/time/timer.c:1682 run_timer_softirq+0x52/0xb0 kernel/time/timer.c:1695 __do_softirq+0x308/0xb7e kernel/softirq.c:292 invoke_softirq kernel/softirq.c:373 [inline] irq_exit+0x17f/0x1c0 kernel/softirq.c:413 exiting_irq arch/x86/include/asm/apic.h:536 [inline] smp_apic_timer_interrupt+0x1cb/0x760 arch/x86/kernel/apic/apic.c:1061 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:807 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:761 [inline] RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xaf/0xd0 kernel/locking/spinlock.c:184 Code: f0 00 52 89 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 75 28 48 83 3d 18 ef 76 01 00 74 15 48 89 df 57 9d <0f> 1f 44 00 00 eb ad e8 1c 6b 25 f9 eb bb 0f 0b 0f 0b e8 9a d7 e7 RSP: 0018:ffff8881c1d4ede8 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13 RAX: dffffc0000000000 RBX: 0000000000000286 RCX: ffffffff8185acea RDX: 1ffffffff12a401e RSI: ffffffff8185ad04 RDI: 0000000000000286 RBP: ffff8881c1d4edf8 R08: ffff8881c2236140 R09: fffffbfff12c7248 R10: fffffbfff12c7248 R11: ffffffff89639243 R12: ffffffff89639240 R13: 0000000000000000 R14: ffff8881bd1712a4 R15: ffff8881bd1712a4 spin_unlock_irqrestore include/linux/spinlock.h:384 [inline] kasan_end_report+0x32/0x4f mm/kasan/report.c:178 kasan_report_error mm/kasan/report.c:359 [inline] kasan_report.cold.8+0x76/0x309 mm/kasan/report.c:412 check_memory_region_inline mm/kasan/kasan.c:260 [inline] check_memory_region+0x13e/0x1b0 mm/kasan/kasan.c:267 kasan_check_read+0x11/0x20 mm/kasan/kasan.c:272 atomic_read include/asm-generic/atomic-instrumented.h:21 [inline] refcount_read include/linux/refcount.h:43 [inline] skb_unref include/linux/skbuff.h:969 [inline] kfree_skb+0xb7/0x580 net/core/skbuff.c:655 tipc_udp_send_msg+0x5a6/0x670 net/tipc/udp_media.c:249 tipc_bearer_xmit_skb+0x171/0x350 net/tipc/bearer.c:502 tipc_enable_bearer+0xc5e/0xf10 net/tipc/bearer.c:327 __tipc_nl_bearer_enable+0x37c/0x4a0 net/tipc/bearer.c:897 tipc_nl_bearer_enable+0x22/0x30 net/tipc/bearer.c:905 genl_family_rcv_msg+0x8a7/0x11a0 net/netlink/genetlink.c:601 genl_rcv_msg+0xc6/0x168 net/netlink/genetlink.c:626 netlink_rcv_skb+0x172/0x440 net/netlink/af_netlink.c:2477 genl_rcv+0x28/0x40 net/netlink/genetlink.c:637 netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline] netlink_unicast+0x5a5/0x760 net/netlink/af_netlink.c:1336 netlink_sendmsg+0xa18/0xfc0 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg+0xd5/0x120 net/socket.c:631 ___sys_sendmsg+0x7fd/0x930 net/socket.c:2116 __sys_sendmsg+0x11d/0x280 net/socket.c:2154 __do_sys_sendmsg net/socket.c:2163 [inline] __se_sys_sendmsg net/socket.c:2161 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2161 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4446f9 Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 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 0f 83 1b d8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffde52c0e58 EFLAGS: 00000213 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00000000004002e0 RCX: 00000000004446f9 RDX: 0000000000000000 RSI: 0000000020000700 RDI: 0000000000000003 RBP: 00000000006cf018 R08: 0000000000000000 R09: 00000000004002e0 R10: 0000000000000000 R11: 0000000000000213 R12: 00000000004023a0 R13: 0000000000402430 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 5993: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0xc7/0xe0 mm/kasan/kasan.c:553 __do_kmalloc_node mm/slab.c:3684 [inline] __kmalloc_node_track_caller+0x50/0x70 mm/slab.c:3698 __kmalloc_reserve.isra.40+0x41/0xe0 net/core/skbuff.c:137 __alloc_skb+0x155/0x770 net/core/skbuff.c:205 __pskb_copy_fclone+0x16b/0xeb0 net/core/skbuff.c:1385 __pskb_copy include/linux/skbuff.h:1053 [inline] pskb_copy include/linux/skbuff.h:2915 [inline] tipc_udp_send_msg+0x44e/0x670 net/tipc/udp_media.c:241 tipc_bearer_xmit_skb+0x171/0x350 net/tipc/bearer.c:502 tipc_disc_timeout+0xb2b/0xfc0 net/tipc/discover.c:332 call_timer_fn+0x272/0x920 kernel/time/timer.c:1326 expire_timers kernel/time/timer.c:1363 [inline] __run_timers+0x7e5/0xc70 kernel/time/timer.c:1682 run_timer_softirq+0x52/0xb0 kernel/time/timer.c:1695 __do_softirq+0x308/0xb7e kernel/softirq.c:292 Freed by task 5993: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/kasan.c:521 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 __cache_free mm/slab.c:3498 [inline] kfree+0xcf/0x230 mm/slab.c:3817 skb_free_head+0x99/0xc0 net/core/skbuff.c:550 skb_release_data+0x70c/0x9a0 net/core/skbuff.c:570 skb_release_all+0x4a/0x60 net/core/skbuff.c:627 __kfree_skb net/core/skbuff.c:641 [inline] kfree_skb+0x1bb/0x580 net/core/skbuff.c:659 tipc_udp_xmit.isra.14+0x420/0xef0 net/tipc/udp_media.c:207 tipc_udp_send_msg+0x398/0x670 net/tipc/udp_media.c:247 tipc_bearer_xmit_skb+0x171/0x350 net/tipc/bearer.c:502 tipc_disc_timeout+0xb2b/0xfc0 net/tipc/discover.c:332 call_timer_fn+0x272/0x920 kernel/time/timer.c:1326 expire_timers kernel/time/timer.c:1363 [inline] __run_timers+0x7e5/0xc70 kernel/time/timer.c:1682 run_timer_softirq+0x52/0xb0 kernel/time/timer.c:1695 __do_softirq+0x308/0xb7e kernel/softirq.c:292 The buggy address belongs to the object at ffff8881cd41d240 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 0 bytes inside of 1024-byte region [ffff8881cd41d240, ffff8881cd41d640) The buggy address belongs to the page: page:ffffea0007350700 count:1 mapcount:0 mapping:ffff8881da800ac0 index:0x0 compound_mapcount: 0 flags: 0x2fffc0000010200(slab|head) raw: 02fffc0000010200 ffffea0007364208 ffffea0007350c08 ffff8881da800ac0 raw: 0000000000000000 ffff8881cd41c040 0000000100000007 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8881cd41d100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881cd41d180: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc >ffff8881cd41d200: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb ^ ffff8881cd41d280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881cd41d300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================