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BUG: KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt+0xb0/0xc0 include/linux/irq-entry-common.h:464
 irqentry_exit_to_kernel_mode_preempt+0xb0/0xc0 include/linux/irq-entry-common.h:464
 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline]
 irqentry_exit+0x82/0xa00 kernel/entry/common.c:164
 sysvec_reschedule_ipi+0x74/0x80 arch/x86/kernel/smp.c:249
 asm_sysvec_reschedule_ipi+0x1f/0x30 arch/x86/include/asm/idtentry.h:702
 mptcp_incoming_options+0x1f22/0x43b0 net/mptcp/options.c:1249
 tcp_data_queue+0x80/0x7c90 net/ipv4/tcp_input.c:5584
 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:3225
 release_sock+0x22d/0x300 net/core/sock.c:3824
 mptcp_subflow_shutdown+0x358/0x690 net/mptcp/protocol.c:3166
 mptcp_check_send_data_fin+0x31b/0x3d0 net/mptcp/protocol.c:3240
 __mptcp_wr_shutdown net/mptcp/protocol.c:3256 [inline]
 __mptcp_close+0x860/0x1360 net/mptcp/protocol.c:3335
 mptcp_close+0x42/0x260 net/mptcp/protocol.c:3389
 inet_release+0x1ee/0x2a0 net/ipv4/af_inet.c:442
 __sock_release net/socket.c:722 [inline]
 sock_close+0xd6/0x2f0 net/socket.c:1515
 __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+0x505/0x2420 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:230 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
 do_syscall_64+0x261/0x3c0 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:1158
 tcp_data_queue+0x80/0x7c90 net/ipv4/tcp_input.c:5584

CPU: 0 UID: 0 PID: 8425 Comm: syz.4.941 Tainted: G             L      syzkaller #0 PREEMPT(lazy) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
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