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BUG: KASAN: use-after-free in tipc_recvmsg+0xf77/0xf90 net/tipc/socket.c:1979
Read of size 4 at addr ffff8880131836c0 by task kworker/u4:1/10

CPU: 1 PID: 10 Comm: kworker/u4:1 Not tainted 5.14.0-rc2-next-20210723-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: tipc_rcv tipc_conn_recv_work
Call Trace:
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:105
 print_address_description.constprop.0.cold+0x6c/0x309 mm/kasan/report.c:256
 __kasan_report mm/kasan/report.c:442 [inline]
 kasan_report.cold+0x83/0xdf mm/kasan/report.c:459
 tipc_recvmsg+0xf77/0xf90 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

Allocated by task 10662:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:434 [inline]
 __kasan_slab_alloc+0x84/0xa0 mm/kasan/common.c:467
 kasan_slab_alloc include/linux/kasan.h:254 [inline]
 slab_post_alloc_hook mm/slab.h:519 [inline]
 slab_alloc_node mm/slub.c:2958 [inline]
 kmem_cache_alloc_node+0x266/0x3e0 mm/slub.c:2994
 __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 10:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38
 kasan_set_track+0x1c/0x30 mm/kasan/common.c:46
 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:360
 ____kasan_slab_free mm/kasan/common.c:366 [inline]
 ____kasan_slab_free mm/kasan/common.c:328 [inline]
 __kasan_slab_free+0xfb/0x130 mm/kasan/common.c:374
 kasan_slab_free include/linux/kasan.h:230 [inline]
 slab_free_hook mm/slub.c:1627 [inline]
 slab_free_freelist_hook+0xdf/0x240 mm/slub.c:1652
 slab_free mm/slub.c:3212 [inline]
 kmem_cache_free+0x8e/0x5a0 mm/slub.c:3228
 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

The buggy address belongs to the object at ffff888013183680
 which belongs to the cache skbuff_fclone_cache of size 472
The buggy address is located 64 bytes inside of
 472-byte region [ffff888013183680, ffff888013183858)
The buggy address belongs to the page:
page:ffffea00004c6080 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888013183400 pfn:0x13182
head:ffffea00004c6080 order:1 compound_mapcount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 ffffea0000aecc80 0000000800000005 ffff8880159fe780
raw: ffff888013183400 00000000800c0008 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 1, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 8465, ts 127035631837, free_ts 123492248270
 prep_new_page mm/page_alloc.c:2424 [inline]
 get_page_from_freelist+0xa72/0x2f80 mm/page_alloc.c:4152
 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5374
 alloc_pages+0x1a3/0x2d0 mm/mempolicy.c:2278
 alloc_slab_page mm/slub.c:1690 [inline]
 allocate_slab+0x32e/0x4b0 mm/slub.c:1830
 new_slab mm/slub.c:1893 [inline]
 new_slab_objects mm/slub.c:2639 [inline]
 ___slab_alloc+0x4ba/0x820 mm/slub.c:2802
 __slab_alloc.constprop.0+0xa7/0xf0 mm/slub.c:2842
 slab_alloc_node mm/slub.c:2924 [inline]
 kmem_cache_alloc_node+0x12c/0x3e0 mm/slub.c:2994
 __alloc_skb+0x20b/0x340 net/core/skbuff.c:414
 alloc_skb_fclone include/linux/skbuff.h:1162 [inline]
 sk_stream_alloc_skb+0x109/0xc30 net/ipv4/tcp.c:887
 tcp_sendmsg_locked+0xc78/0x2f10 net/ipv4/tcp.c:1309
 tcp_sendmsg+0x2b/0x40 net/ipv4/tcp.c:1461
 inet_sendmsg+0x99/0xe0 net/ipv4/af_inet.c:821
 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
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1338 [inline]
 free_pcp_prepare+0x373/0x860 mm/page_alloc.c:1389
 free_unref_page_prepare mm/page_alloc.c:3315 [inline]
 free_unref_page+0x19/0x690 mm/page_alloc.c:3394
 qlink_free mm/kasan/quarantine.c:146 [inline]
 qlist_free_all+0x5a/0xc0 mm/kasan/quarantine.c:165
 kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:272
 __kasan_slab_alloc+0x8e/0xa0 mm/kasan/common.c:444
 kasan_slab_alloc include/linux/kasan.h:254 [inline]
 slab_post_alloc_hook mm/slab.h:519 [inline]
 slab_alloc_node mm/slub.c:2958 [inline]
 kmem_cache_alloc_node+0x266/0x3e0 mm/slub.c:2994
 __alloc_skb+0x20b/0x340 net/core/skbuff.c:414
 alloc_skb_fclone include/linux/skbuff.h:1162 [inline]
 sk_stream_alloc_skb+0x109/0xc30 net/ipv4/tcp.c:887
 tcp_sendmsg_locked+0xc78/0x2f10 net/ipv4/tcp.c:1309
 tcp_sendmsg+0x2b/0x40 net/ipv4/tcp.c:1461
 inet_sendmsg+0x99/0xe0 net/ipv4/af_inet.c:821
 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

Memory state around the buggy address:
 ffff888013183580: fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc
 ffff888013183600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888013183680: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                           ^
 ffff888013183700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888013183780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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