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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:3374
 x64_setup_rt_frame+0x1e74/0x2400 arch/x86/kernel/signal_64.c:194
 setup_rt_frame arch/x86/kernel/signal.c:222 [inline]
 handle_signal arch/x86/kernel/signal.c:266 [inline]
 arch_do_signal_or_restart+0x626/0xca0 arch/x86/kernel/signal.c:311
 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+0x5b/0x160 kernel/entry/common.c:212
 do_syscall_64+0x79/0x140 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:17 [inline]
 collect_signal kernel/signal.c:596 [inline]
 __dequeue_signal+0x548/0xa00 kernel/signal.c:625
 dequeue_signal+0x14b/0xb10 kernel/signal.c:648
 get_signal+0xc3f/0x2d10 kernel/signal.c:2784
 arch_do_signal_or_restart+0x53/0xca0 arch/x86/kernel/signal.c:309
 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+0x5b/0x160 kernel/entry/common.c:212
 do_syscall_64+0x79/0x140 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Uninit was created at:
 slab_free_hook mm/slub.c:1770 [inline]
 slab_free_freelist_hook mm/slub.c:1826 [inline]
 slab_free mm/slub.c:3809 [inline]
 kmem_cache_free+0x66f/0x1250 mm/slub.c:3831
 __sigqueue_free kernel/signal.c:460 [inline]
 collect_signal kernel/signal.c:603 [inline]
 __dequeue_signal+0x998/0xa00 kernel/signal.c:625
 dequeue_signal+0x14b/0xb10 kernel/signal.c:648
 get_signal+0xc3f/0x2d10 kernel/signal.c:2784
 arch_do_signal_or_restart+0x53/0xca0 arch/x86/kernel/signal.c:309
 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+0x5b/0x160 kernel/entry/common.c:212
 do_syscall_64+0x79/0x140 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Bytes 12-15 of 48 are uninitialized
Memory access of size 48 starts at ffff888028ff3e30
Data copied to user address 000000c0000fbbf0

CPU: 1 PID: 5222 Comm: syz-execprog Not tainted 6.7.0-syzkaller-00562-g9f8413c4a66f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
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