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BUG: KMSAN: uninit-value in do_slab_free mm/slub.c:3016 [inline]
BUG: KMSAN: uninit-value in slab_free mm/slub.c:3039 [inline]
BUG: KMSAN: uninit-value in kmem_cache_free+0x3df/0x2b70 mm/slub.c:3054
CPU: 0 PID: 14622 Comm: syz-executor.4 Not tainted 5.3.0-rc7+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x191/0x1f0 lib/dump_stack.c:113
 kmsan_report+0x162/0x2d0 mm/kmsan/kmsan_report.c:109
 __msan_warning+0x75/0xe0 mm/kmsan/kmsan_instr.c:294
 do_slab_free mm/slub.c:3016 [inline]
 slab_free mm/slub.c:3039 [inline]
 kmem_cache_free+0x3df/0x2b70 mm/slub.c:3054
 kfree_skbmem net/core/skbuff.c:644 [inline]
 __kfree_skb net/core/skbuff.c:680 [inline]
 kfree_skb+0x473/0x4c0 net/core/skbuff.c:697
 __udp4_lib_mcast_deliver net/ipv4/udp.c:2164 [inline]
 __udp4_lib_rcv+0x490d/0x4a70 net/ipv4/udp.c:2291
 udp_rcv+0x5c/0x70 net/ipv4/udp.c:2466
 ip_protocol_deliver_rcu+0x694/0xbc0 net/ipv4/ip_input.c:204
 ip_local_deliver_finish net/ipv4/ip_input.c:231 [inline]
 NF_HOOK include/linux/netfilter.h:305 [inline]
 ip_local_deliver+0x62a/0x7c0 net/ipv4/ip_input.c:252
 dst_input include/net/dst.h:442 [inline]
 ip_rcv_finish net/ipv4/ip_input.c:413 [inline]
 NF_HOOK include/linux/netfilter.h:305 [inline]
 ip_rcv+0x6c5/0x740 net/ipv4/ip_input.c:523
 __netif_receive_skb_one_core net/core/dev.c:5004 [inline]
 __netif_receive_skb net/core/dev.c:5118 [inline]
 process_backlog+0xef5/0x1410 net/core/dev.c:5929
 napi_poll net/core/dev.c:6352 [inline]
 net_rx_action+0x74b/0x1950 net/core/dev.c:6418
 __do_softirq+0x4a1/0x83a kernel/softirq.c:293
 do_softirq_own_stack+0x49/0x80 arch/x86/entry/entry_64.S:1093
 </IRQ>
 do_softirq+0xed/0x150 kernel/softirq.c:338
 netif_rx_ni+0x208/0x3c0 net/core/dev.c:4562
 dev_loopback_xmit+0x607/0x670 net/core/dev.c:3584
 ip_mc_finish_output+0x484/0x6d0 net/ipv4/ip_output.c:357
 NF_HOOK include/linux/netfilter.h:305 [inline]
 ip_mc_output+0xc6d/0x1090 net/ipv4/ip_output.c:412
 dst_output include/net/dst.h:436 [inline]
 ip_local_out net/ipv4/ip_output.c:125 [inline]
 ip_send_skb+0x179/0x360 net/ipv4/ip_output.c:1554
 udp_send_skb+0xeda/0x1870 net/ipv4/udp.c:887
 udp_sendmsg+0x397c/0x4170 net/ipv4/udp.c:1174
 inet_sendmsg+0x276/0x2e0 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+0xbc/0xf0 arch/x86/entry/common.c:297
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x4598e9
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:00007f63e07e2c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00000000004598e9
RDX: 04000000000001a8 RSI: 0000000020007fc0 RDI: 0000000000000003
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f63e07e36d4
R13: 00000000004c70a7 R14: 00000000004dc768 R15: 00000000ffffffff

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:189 [inline]
 kmsan_internal_chain_origin+0xcc/0x150 mm/kmsan/kmsan.c:347
 __msan_chain_origin+0x6b/0xe0 mm/kmsan/kmsan_instr.c:190
 ___slab_alloc+0x1dbc/0x1fb0 mm/slub.c:2634
 __slab_alloc mm/slub.c:2687 [inline]
 slab_alloc_node mm/slub.c:2750 [inline]
 slab_alloc mm/slub.c:2799 [inline]
 kmem_cache_alloc+0xade/0xd10 mm/slub.c:2804
 skb_clone+0x326/0x5d0 net/core/skbuff.c:1448
 ip_mc_output+0x934/0x1090 net/ipv4/ip_output.c:410
 dst_output include/net/dst.h:436 [inline]
 ip_local_out net/ipv4/ip_output.c:125 [inline]
 ip_send_skb+0x179/0x360 net/ipv4/ip_output.c:1554
 udp_send_skb+0xeda/0x1870 net/ipv4/udp.c:887
 udp_sendmsg+0x397c/0x4170 net/ipv4/udp.c:1174
 inet_sendmsg+0x276/0x2e0 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+0xbc/0xf0 arch/x86/entry/common.c:297
 entry_SYSCALL_64_after_hwframe+0x63/0xe7

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:189 [inline]
 kmsan_internal_poison_shadow+0x58/0xb0 mm/kmsan/kmsan.c:148
 kmsan_slab_free+0x8d/0x100 mm/kmsan/kmsan_hooks.c:195
 slab_free_freelist_hook mm/slub.c:1472 [inline]
 slab_free mm/slub.c:3038 [inline]
 kmem_cache_free_bulk+0x3ad9/0x3f50 mm/slub.c:3163
 __kfree_skb_flush+0xb0/0x100 net/core/skbuff.c:862
 net_rx_action+0x1908/0x1950 net/core/dev.c:6441
 __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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