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BUG: KMSAN: kernel-infoleak-after-free in instrument_copy_to_user include/linux/instrumented.h:114 [inline]
BUG: KMSAN: kernel-infoleak-after-free in _copy_to_user+0xbc/0x100 lib/usercopy.c:40
 instrument_copy_to_user include/linux/instrumented.h:114 [inline]
 _copy_to_user+0xbc/0x100 lib/usercopy.c:40
 copy_to_user include/linux/uaccess.h:191 [inline]
 copy_siginfo_to_user+0x40/0x130 kernel/signal.c:3362
 x64_setup_rt_frame+0x1e74/0x2470 arch/x86/kernel/signal_64.c:194
 setup_rt_frame arch/x86/kernel/signal.c:223 [inline]
 handle_signal arch/x86/kernel/signal.c:267 [inline]
 arch_do_signal_or_restart+0x626/0xca0 arch/x86/kernel/signal.c:312
 exit_to_user_mode_loop kernel/entry/common.c:105 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:201 [inline]
 syscall_exit_to_user_mode+0x5c/0x160 kernel/entry/common.c:212
 do_syscall_64+0xdc/0x1e0 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Uninit was stored to memory at:
 copy_siginfo include/linux/signal.h:18 [inline]
 collect_signal kernel/signal.c:586 [inline]
 __dequeue_signal+0x501/0xad0 kernel/signal.c:615
 dequeue_signal+0x14b/0xb10 kernel/signal.c:638
 get_signal+0xb4d/0x2d80 kernel/signal.c:2773
 arch_do_signal_or_restart+0x53/0xca0 arch/x86/kernel/signal.c:310
 exit_to_user_mode_loop kernel/entry/common.c:105 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:201 [inline]
 syscall_exit_to_user_mode+0x5c/0x160 kernel/entry/common.c:212
 do_syscall_64+0xdc/0x1e0 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Uninit was created at:
 slab_free_hook mm/slub.c:2088 [inline]
 slab_free mm/slub.c:4299 [inline]
 kmem_cache_free+0x256/0xa40 mm/slub.c:4363
 __sigqueue_free kernel/signal.c:450 [inline]
 collect_signal kernel/signal.c:593 [inline]
 __dequeue_signal+0xa58/0xad0 kernel/signal.c:615
 dequeue_signal+0x14b/0xb10 kernel/signal.c:638
 get_signal+0xb4d/0x2d80 kernel/signal.c:2773
 arch_do_signal_or_restart+0x53/0xca0 arch/x86/kernel/signal.c:310
 exit_to_user_mode_loop kernel/entry/common.c:105 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 irqentry_exit_to_user_mode+0xa1/0x150 kernel/entry/common.c:225
 irqentry_exit+0x16/0x50 kernel/entry/common.c:328
 sysvec_apic_timer_interrupt+0x4f/0x90 arch/x86/kernel/apic/apic.c:1076
 asm_sysvec_apic_timer_interrupt+0x1f/0x30 arch/x86/include/asm/idtentry.h:649

Bytes 12-15 of 48 are uninitialized
Memory access of size 48 starts at ffff888102eebe20
Data copied to user address 000000c000063bf0

CPU: 1 PID: 5048 Comm: syz-execprog Not tainted 6.8.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
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