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BUG: KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt+0xb0/0xc0 include/linux/irq-entry-common.h:474
 irqentry_exit_to_kernel_mode_preempt+0xb0/0xc0 include/linux/irq-entry-common.h:474
 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:549 [inline]
 irqentry_exit+0x7b/0x820 kernel/entry/common.c:164
 sysvec_apic_timer_interrupt+0x52/0x90 arch/x86/kernel/apic/apic.c:1061
 asm_sysvec_apic_timer_interrupt+0x1f/0x30 arch/x86/include/asm/idtentry.h:697
 __msan_metadata_ptr_for_load_4+0x5/0x40 mm/kmsan/instrumentation.c:93
 tcp_rcv_established+0x19bb/0x3200 net/ipv4/tcp_input.c:6656
 tcp_v4_do_rcv+0xc5b/0x1b70 net/ipv4/tcp_ipv4.c:1851
 sk_backlog_rcv include/net/sock.h:1190 [inline]
 __release_sock+0x360/0x7d0 net/core/sock.c:3216
 release_sock+0x22d/0x300 net/core/sock.c:3815
 mptcp_subflow_shutdown+0x358/0x690 net/mptcp/protocol.c:3144
 mptcp_check_send_data_fin+0x31b/0x3d0 net/mptcp/protocol.c:3218
 __mptcp_wr_shutdown net/mptcp/protocol.c:3234 [inline]
 __mptcp_close+0x860/0x1360 net/mptcp/protocol.c:3313
 mptcp_close+0x42/0x260 net/mptcp/protocol.c:3367
 inet_release+0x1ee/0x2a0 net/ipv4/af_inet.c:442
 __sock_release net/socket.c:722 [inline]
 sock_close+0xd6/0x2f0 net/socket.c:1514
 __fput+0x60e/0x1010 fs/file_table.c:510
 ____fput+0x25/0x30 fs/file_table.c:538
 task_work_run+0x208/0x2b0 kernel/task_work.c:233
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 __exit_to_user_mode_loop kernel/entry/common.c:67 [inline]
 exit_to_user_mode_loop+0x306/0x1ea0 kernel/entry/common.c:98
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:238 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
 do_syscall_64+0x236/0xf80 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Local variable mp_opt created at:
 mptcp_incoming_options+0x11d/0x43b0 net/mptcp/options.c:1171
 tcp_data_queue+0x80/0x7c90 net/ipv4/tcp_input.c:5584

CPU: 0 UID: 0 PID: 10313 Comm: syz.0.1815 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
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