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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_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
 kmsan_get_metadata+0x17/0x160 mm/kmsan/shadow.c:125
 kmsan_get_shadow_origin_ptr+0x35/0xb0 mm/kmsan/shadow.c:97
 get_shadow_origin_ptr mm/kmsan/instrumentation.c:38 [inline]
 __msan_metadata_ptr_for_load_4+0x24/0x40 mm/kmsan/instrumentation.c:93
 tcp_data_queue+0xdc/0x7c90 net/ipv4/tcp_input.c:5589
 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_push_release net/mptcp/protocol.c:1584 [inline]
 __mptcp_push_pending+0xae6/0xe60 net/mptcp/protocol.c:1723
 mptcp_sendmsg+0x2993/0x2e50 net/mptcp/protocol.c:2037
 inet_sendmsg+0x25e/0x290 net/ipv4/af_inet.c:866
 sock_sendmsg_nosec net/socket.c:787 [inline]
 __sock_sendmsg net/socket.c:802 [inline]
 __sys_sendto+0x8bc/0xae0 net/socket.c:2266
 __do_compat_sys_socketcall net/compat.c:-1 [inline]
 __se_compat_sys_socketcall net/compat.c:423 [inline]
 __ia32_compat_sys_socketcall+0x717/0x1b70 net/compat.c:423
 ia32_sys_call+0x2c57/0x4360 arch/x86/include/generated/asm/syscalls_32.h:103
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
 do_int80_emulation+0x177/0x380 arch/x86/entry/syscall_32.c:172
 asm_int80_emulation+0x1f/0x30 arch/x86/include/asm/idtentry.h:621

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: 1 UID: 0 PID: 20430 Comm: syz.2.2729 Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
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