RBP: 00007f7bf8546ca0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000004 R13: 00007ffdccc835ff R14: 00007f7bf85479c0 R15: 000000000118bf2c Failed do clone local mcast rcv buffer ================================================================== BUG: KASAN: use-after-free in __skb_unlink include/linux/skbuff.h:1911 [inline] BUG: KASAN: use-after-free in __skb_dequeue include/linux/skbuff.h:1931 [inline] BUG: KASAN: use-after-free in __skb_queue_purge include/linux/skbuff.h:2648 [inline] BUG: KASAN: use-after-free in tipc_mcast_xmit+0x71c/0x7b0 net/tipc/bcast.c:322 Read of size 8 at addr ffff88806fff8280 by task syz-executor.2/6024 CPU: 1 PID: 6024 Comm: syz-executor.2 Not tainted 4.19.152-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/0x2fe lib/dump_stack.c:118 print_address_description.cold+0x54/0x219 mm/kasan/report.c:256 kasan_report_error.cold+0x8a/0x1c7 mm/kasan/report.c:354 kasan_report mm/kasan/report.c:412 [inline] __asan_report_load8_noabort+0x88/0x90 mm/kasan/report.c:433 __skb_unlink include/linux/skbuff.h:1911 [inline] __skb_dequeue include/linux/skbuff.h:1931 [inline] __skb_queue_purge include/linux/skbuff.h:2648 [inline] tipc_mcast_xmit+0x71c/0x7b0 net/tipc/bcast.c:322 tipc_sendmcast+0xa1f/0xba0 net/tipc/socket.c:808 __tipc_sendmsg+0xe82/0x1320 net/tipc/socket.c:1342 tipc_sendmsg+0x4c/0x70 net/tipc/socket.c:1276 sock_sendmsg_nosec net/socket.c:622 [inline] sock_sendmsg+0xc3/0x120 net/socket.c:632 ___sys_sendmsg+0x7bb/0x8e0 net/socket.c:2115 __sys_sendmsg net/socket.c:2153 [inline] __do_sys_sendmsg net/socket.c:2162 [inline] __se_sys_sendmsg net/socket.c:2160 [inline] __x64_sys_sendmsg+0x132/0x220 net/socket.c:2160 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45deb9 Code: 0d b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 db b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f7bf8546c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 000000000002e7c0 RCX: 000000000045deb9 RDX: 0000000000000000 RSI: 0000000020001380 RDI: 0000000000000004 RBP: 00007f7bf8546ca0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000004 R13: 00007ffdccc835ff R14: 00007f7bf85479c0 R15: 000000000118bf2c Allocated by task 6024: kmem_cache_alloc_node+0x146/0x3b0 mm/slab.c:3649 __alloc_skb+0x71/0x560 net/core/skbuff.c:193 alloc_skb_fclone include/linux/skbuff.h:1037 [inline] tipc_buf_acquire+0x28/0xf0 net/tipc/msg.c:66 tipc_msg_build+0x67a/0x1010 net/tipc/msg.c:309 tipc_sendmcast+0x852/0xba0 net/tipc/socket.c:804 __tipc_sendmsg+0xe82/0x1320 net/tipc/socket.c:1342 tipc_sendmsg+0x4c/0x70 net/tipc/socket.c:1276 sock_sendmsg_nosec net/socket.c:622 [inline] sock_sendmsg+0xc3/0x120 net/socket.c:632 ___sys_sendmsg+0x7bb/0x8e0 net/socket.c:2115 __sys_sendmsg net/socket.c:2153 [inline] __do_sys_sendmsg net/socket.c:2162 [inline] __se_sys_sendmsg net/socket.c:2160 [inline] __x64_sys_sendmsg+0x132/0x220 net/socket.c:2160 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 6024: __cache_free mm/slab.c:3503 [inline] kmem_cache_free+0x7f/0x260 mm/slab.c:3765 kfree_skbmem+0xa4/0x140 net/core/skbuff.c:607 __kfree_skb net/core/skbuff.c:646 [inline] kfree_skb+0x127/0x3d0 net/core/skbuff.c:663 tipc_buf_append+0x655/0xc10 net/tipc/msg.c:188 tipc_msg_reassemble+0x175/0x4f0 net/tipc/msg.c:649 tipc_mcast_xmit+0x525/0x7b0 net/tipc/bcast.c:305 tipc_sendmcast+0xa1f/0xba0 net/tipc/socket.c:808 __tipc_sendmsg+0xe82/0x1320 net/tipc/socket.c:1342 tipc_sendmsg+0x4c/0x70 net/tipc/socket.c:1276 sock_sendmsg_nosec net/socket.c:622 [inline] sock_sendmsg+0xc3/0x120 net/socket.c:632 ___sys_sendmsg+0x7bb/0x8e0 net/socket.c:2115 __sys_sendmsg net/socket.c:2153 [inline] __do_sys_sendmsg net/socket.c:2162 [inline] __se_sys_sendmsg net/socket.c:2160 [inline] __x64_sys_sendmsg+0x132/0x220 net/socket.c:2160 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff88806fff8280 which belongs to the cache skbuff_fclone_cache of size 472 The buggy address is located 0 bytes inside of 472-byte region [ffff88806fff8280, ffff88806fff8458) The buggy address belongs to the page: page:ffffea0001bffe00 count:1 mapcount:0 mapping:ffff88823b846e00 index:0x0 flags: 0xfff00000000100(slab) raw: 00fff00000000100 ffffea00028c29c8 ffffea0002bc5788 ffff88823b846e00 raw: 0000000000000000 ffff88806fff8000 0000000100000006 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88806fff8180: 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc ffff88806fff8200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88806fff8280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88806fff8300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88806fff8380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================