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BUG: KMSAN: kernel-infoleak-after-free in instrument_copy_to_user include/linux/instrumented.h:121 [inline]
BUG: KMSAN: kernel-infoleak-after-free in copyout lib/iov_iter.c:154 [inline]
BUG: KMSAN: kernel-infoleak-after-free in _copy_to_iter+0x6ef/0x25a0 lib/iov_iter.c:670
 instrument_copy_to_user include/linux/instrumented.h:121 [inline]
 copyout lib/iov_iter.c:154 [inline]
 _copy_to_iter+0x6ef/0x25a0 lib/iov_iter.c:670
 copy_to_iter include/linux/uio.h:162 [inline]
 simple_copy_to_iter+0xf3/0x140 net/core/datagram.c:519
 __skb_datagram_iter+0x2d5/0x11b0 net/core/datagram.c:425
 skb_copy_datagram_iter+0xdc/0x270 net/core/datagram.c:533
 skb_copy_datagram_msg include/linux/skbuff.h:3696 [inline]
 packet_recvmsg+0x790/0x2170 net/packet/af_packet.c:3452
 sock_recvmsg_nosec net/socket.c:948 [inline]
 sock_recvmsg net/socket.c:966 [inline]
 __sys_recvfrom+0x795/0xa10 net/socket.c:2097
 __compat_sys_recvfrom net/compat.c:390 [inline]
 __do_compat_sys_recvfrom net/compat.c:403 [inline]
 __se_compat_sys_recvfrom net/compat.c:399 [inline]
 __ia32_compat_sys_recvfrom+0x1a3/0x210 net/compat.c:399
 do_syscall_32_irqs_on arch/x86/entry/common.c:113 [inline]
 __do_fast_syscall_32+0x96/0xf0 arch/x86/entry/common.c:179
 do_fast_syscall_32+0x34/0x70 arch/x86/entry/common.c:204
 do_SYSENTER_32+0x1b/0x20 arch/x86/entry/common.c:247
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c

Uninit was stored to memory at:
 skb_put_data include/linux/skbuff.h:2376 [inline]
 netlink_to_full_skb net/netlink/af_netlink.c:179 [inline]
 __netlink_deliver_tap_skb net/netlink/af_netlink.c:296 [inline]
 __netlink_deliver_tap+0x626/0xe10 net/netlink/af_netlink.c:323
 netlink_deliver_tap net/netlink/af_netlink.c:336 [inline]
 netlink_deliver_tap_kernel net/netlink/af_netlink.c:345 [inline]
 netlink_unicast_kernel net/netlink/af_netlink.c:1316 [inline]
 netlink_unicast+0x1233/0x1360 net/netlink/af_netlink.c:1343
 netlink_sendmsg+0x14d9/0x1720 net/netlink/af_netlink.c:1919
 sock_sendmsg_nosec net/socket.c:705 [inline]
 sock_sendmsg net/socket.c:725 [inline]
 ____sys_sendmsg+0xe11/0x12c0 net/socket.c:2413
 ___sys_sendmsg net/socket.c:2467 [inline]
 __sys_sendmsg+0x704/0x840 net/socket.c:2496
 __compat_sys_sendmsg net/compat.c:347 [inline]
 __do_compat_sys_sendmsg net/compat.c:354 [inline]
 __se_compat_sys_sendmsg net/compat.c:351 [inline]
 __ia32_compat_sys_sendmsg+0xed/0x130 net/compat.c:351
 do_syscall_32_irqs_on arch/x86/entry/common.c:113 [inline]
 __do_fast_syscall_32+0x96/0xf0 arch/x86/entry/common.c:179
 do_fast_syscall_32+0x34/0x70 arch/x86/entry/common.c:204
 do_SYSENTER_32+0x1b/0x20 arch/x86/entry/common.c:247
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c

Uninit was created at:
 free_pages_prepare mm/page_alloc.c:1309 [inline]
 free_pcp_prepare+0x6b/0x860 mm/page_alloc.c:1432
 free_unref_page_prepare mm/page_alloc.c:3334 [inline]
 free_unref_page_list+0x114/0xe30 mm/page_alloc.c:3450
 release_pages+0x1e9b/0x1ed0 mm/swap.c:980
 free_pages_and_swap_cache+0x4f9/0x520 mm/swap_state.c:320
 tlb_batch_pages_flush mm/mmu_gather.c:51 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:244 [inline]
 tlb_flush_mmu+0x8f9/0xa80 mm/mmu_gather.c:251
 tlb_finish_mmu+0x130/0x310 mm/mmu_gather.c:351
 exit_mmap+0x7c0/0xe20 mm/mmap.c:3180
 __mmput+0x1bf/0x6c0 kernel/fork.c:1116
 mmput+0x9b/0xc0 kernel/fork.c:1137
 exit_mm+0x1f5/0x350 kernel/exit.c:508
 do_exit+0xeb0/0x4010 kernel/exit.c:795
 do_group_exit+0x3cc/0x420 kernel/exit.c:937
 get_signal+0x17d0/0x2c70 kernel/signal.c:2863
 arch_do_signal_or_restart+0x9d/0xdd0 arch/x86/kernel/signal.c:868
 handle_signal_work kernel/entry/common.c:148 [inline]
 exit_to_user_mode_loop+0x1f6/0x490 kernel/entry/common.c:172
 exit_to_user_mode_prepare kernel/entry/common.c:207 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]
 syscall_exit_to_user_mode+0x7e/0xc0 kernel/entry/common.c:300
 __do_fast_syscall_32+0xa5/0xf0 arch/x86/entry/common.c:182
 do_fast_syscall_32+0x34/0x70 arch/x86/entry/common.c:204
 do_SYSENTER_32+0x1b/0x20 arch/x86/entry/common.c:247
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c

Bytes 4036-4095 of 4096 are uninitialized
Memory access of size 4096 starts at ffff888070892000
Data copied to user address 00000000200011c0

CPU: 0 PID: 1767 Comm: syz-executor.4 Not tainted 5.17.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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