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BUG: KFENCE: use-after-free read in tipc_recvmsg+0x77f/0xf90 net/tipc/socket.c:1979

Use-after-free read at 0xffff88823bc40040 (in kfence-#31):
 tipc_recvmsg+0x77f/0xf90 net/tipc/socket.c:1979
 sock_recvmsg_nosec net/socket.c:943 [inline]
 sock_recvmsg net/socket.c:961 [inline]
 sock_recvmsg+0xca/0x110 net/socket.c:957
 tipc_conn_rcv_from_sock+0x162/0x2f0 net/tipc/topsrv.c:398
 tipc_conn_recv_work+0xeb/0x190 net/tipc/topsrv.c:421
 process_one_work+0x98d/0x1630 kernel/workqueue.c:2276
 worker_thread+0x658/0x11f0 kernel/workqueue.c:2422
 kthread+0x3e5/0x4d0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

kfence-#31: 0xffff88823bc40000-0xffff88823bc401d7, size=472, cache=skbuff_fclone_cache

allocated by task 13771 on cpu 1 at 326.936659s:
 __alloc_skb+0x20b/0x340 net/core/skbuff.c:414
 alloc_skb_fclone include/linux/skbuff.h:1162 [inline]
 tipc_buf_acquire+0x25/0xe0 net/tipc/msg.c:72
 tipc_msg_build+0xf7/0x10a0 net/tipc/msg.c:386
 __tipc_sendstream+0x6d0/0x1150 net/tipc/socket.c:1610
 tipc_sendstream+0x4c/0x70 net/tipc/socket.c:1541
 sock_sendmsg_nosec net/socket.c:703 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:723
 sock_write_iter+0x289/0x3c0 net/socket.c:1056
 call_write_iter include/linux/fs.h:2152 [inline]
 new_sync_write+0x426/0x650 fs/read_write.c:518
 vfs_write+0x75a/0xa40 fs/read_write.c:605
 ksys_write+0x1ee/0x250 fs/read_write.c:658
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

freed by task 107 on cpu 0 at 326.938247s:
 kfree_skbmem+0x166/0x1b0 net/core/skbuff.c:720
 __kfree_skb net/core/skbuff.c:756 [inline]
 kfree_skb net/core/skbuff.c:773 [inline]
 kfree_skb+0x140/0x3f0 net/core/skbuff.c:767
 tipc_recvmsg+0x70d/0xf90 net/tipc/socket.c:1977
 sock_recvmsg_nosec net/socket.c:943 [inline]
 sock_recvmsg net/socket.c:961 [inline]
 sock_recvmsg+0xca/0x110 net/socket.c:957
 tipc_conn_rcv_from_sock+0x162/0x2f0 net/tipc/topsrv.c:398
 tipc_conn_recv_work+0xeb/0x190 net/tipc/topsrv.c:421
 process_one_work+0x98d/0x1630 kernel/workqueue.c:2276
 worker_thread+0x658/0x11f0 kernel/workqueue.c:2422
 kthread+0x3e5/0x4d0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

CPU: 0 PID: 107 Comm: kworker/u4:4 Not tainted 5.14.0-rc2-next-20210722-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: tipc_rcv tipc_conn_recv_work
RIP: 0010:tipc_recvmsg+0x77f/0xf90 net/tipc/socket.c:1979
Code: 40 38 f1 40 0f 9e c6 84 c9 0f 95 c1 40 84 ce 0f 85 00 08 00 00 83 e0 07 38 c2 0f 9e c1 84 d2 0f 95 c0 84 c1 0f 85 eb 07 00 00 <8b> 5b 40 31 ff 89 de e8 35 94 d2 f8 85 db 0f 85 ea fe ff ff e8 e8
RSP: 0018:ffffc9000123f9e8 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff88823bc40000 RCX: 0000000000000001
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000003
RBP: ffff88802761e800 R08: 0000000000000000 R09: ffffffff90267d57
R10: ffffffff88a3343c R11: 0000000000000000 R12: ffff88823bc40040
R13: 0000000000000000 R14: 000000000000001c R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffff88823bc40040 CR3: 000000007b036000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 sock_recvmsg_nosec net/socket.c:943 [inline]
 sock_recvmsg net/socket.c:961 [inline]
 sock_recvmsg+0xca/0x110 net/socket.c:957
 tipc_conn_rcv_from_sock+0x162/0x2f0 net/tipc/topsrv.c:398
 tipc_conn_recv_work+0xeb/0x190 net/tipc/topsrv.c:421
 process_one_work+0x98d/0x1630 kernel/workqueue.c:2276
 worker_thread+0x658/0x11f0 kernel/workqueue.c:2422
 kthread+0x3e5/0x4d0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
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