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BUG: KMSAN: use-after-free in do_slab_free mm/slub.c:3018 [inline]
BUG: KMSAN: use-after-free in slab_free mm/slub.c:3041 [inline]
BUG: KMSAN: use-after-free in kmem_cache_free+0x3df/0x2b70 mm/slub.c:3056
CPU: 0 PID: 6926 Comm: syz-executor.3 Not tainted 5.4.0-rc3+ #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+0x191/0x1f0 lib/dump_stack.c:113
 kmsan_report+0x14a/0x2f0 mm/kmsan/kmsan_report.c:110
 __msan_warning+0x73/0xf0 mm/kmsan/kmsan_instr.c:245
 do_slab_free mm/slub.c:3018 [inline]
 slab_free mm/slub.c:3041 [inline]
 kmem_cache_free+0x3df/0x2b70 mm/slub.c:3056
 kfree_skbmem net/core/skbuff.c:644 [inline]
 __kfree_skb+0x1dd/0x210 net/core/skbuff.c:680
 dccp_v6_do_rcv+0xcd1/0x11f0 net/dccp/ipv6.c:673
 sk_backlog_rcv include/net/sock.h:945 [inline]
 __release_sock+0x448/0x640 net/core/sock.c:2435
 release_sock+0x99/0x2a0 net/core/sock.c:2951
 dccp_sendmsg+0x1017/0x1270 net/dccp/proto.c:814
 inet_sendmsg+0x2d8/0x2e0 net/ipv4/af_inet.c:807
 sock_sendmsg_nosec net/socket.c:637 [inline]
 sock_sendmsg net/socket.c:657 [inline]
 ___sys_sendmsg+0x12c4/0x1590 net/socket.c:2311
 __sys_sendmmsg+0x53a/0xae0 net/socket.c:2413
 __do_sys_sendmmsg net/socket.c:2442 [inline]
 __se_sys_sendmmsg+0xbd/0xe0 net/socket.c:2439
 __x64_sys_sendmmsg+0x56/0x70 net/socket.c:2439
 do_syscall_64+0xb6/0x160 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x459a59
Code: fd b7 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 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f07dab6bc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000459a59
RDX: 04000000000000d0 RSI: 0000000020003d40 RDI: 0000000000000006
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f07dab6c6d4
R13: 00000000004c74b8 R14: 00000000004dd1a8 R15: 00000000ffffffff

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:151 [inline]
 kmsan_internal_chain_origin+0xbd/0x170 mm/kmsan/kmsan.c:319
 __msan_chain_origin+0x6b/0xe0 mm/kmsan/kmsan_instr.c:179
 ___slab_alloc+0x1dbc/0x1fb0 mm/slub.c:2636
 __slab_alloc mm/slub.c:2689 [inline]
 slab_alloc_node mm/slub.c:2752 [inline]
 slab_alloc mm/slub.c:2801 [inline]
 kmem_cache_alloc+0xade/0xd10 mm/slub.c:2806
 skb_clone+0x326/0x5d0 net/core/skbuff.c:1448
 dccp_v6_do_rcv+0x2df/0x11f0 net/dccp/ipv6.c:603
 sk_backlog_rcv include/net/sock.h:945 [inline]
 __release_sock+0x448/0x640 net/core/sock.c:2435
 release_sock+0x99/0x2a0 net/core/sock.c:2951
 dccp_sendmsg+0x1017/0x1270 net/dccp/proto.c:814
 inet_sendmsg+0x2d8/0x2e0 net/ipv4/af_inet.c:807
 sock_sendmsg_nosec net/socket.c:637 [inline]
 sock_sendmsg net/socket.c:657 [inline]
 ___sys_sendmsg+0x12c4/0x1590 net/socket.c:2311
 __sys_sendmmsg+0x53a/0xae0 net/socket.c:2413
 __do_sys_sendmmsg net/socket.c:2442 [inline]
 __se_sys_sendmmsg+0xbd/0xe0 net/socket.c:2439
 __x64_sys_sendmmsg+0x56/0x70 net/socket.c:2439
 do_syscall_64+0xb6/0x160 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:151 [inline]
 kmsan_internal_poison_shadow+0x60/0x110 mm/kmsan/kmsan.c:134
 kmsan_slab_free+0x8d/0x100 mm/kmsan/kmsan_hooks.c:108
 slab_free_freelist_hook mm/slub.c:1473 [inline]
 slab_free mm/slub.c:3040 [inline]
 kmem_cache_free_bulk+0x3ad9/0x3f10 mm/slub.c:3165
 __kfree_skb_flush+0xb0/0x100 net/core/skbuff.c:862
 net_rx_action+0x1a5e/0x1aa0 net/core/dev.c:6483
 __do_softirq+0x4a1/0x83a kernel/softirq.c:293
 run_ksoftirqd+0x25/0x40 kernel/softirq.c:607
 smpboot_thread_fn+0x4a3/0x990 kernel/smpboot.c:165
 kthread+0x4b5/0x4f0 kernel/kthread.c:256
 ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:355
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