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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 _inline_copy_to_user include/linux/uaccess.h:196 [inline]
BUG: KMSAN: kernel-infoleak-after-free in _copy_to_user+0xc8/0x120 lib/usercopy.c:26
 instrument_copy_to_user include/linux/instrumented.h:114 [inline]
 _inline_copy_to_user include/linux/uaccess.h:196 [inline]
 _copy_to_user+0xc8/0x120 lib/usercopy.c:26
 copy_to_user include/linux/uaccess.h:225 [inline]
 copy_siginfo_to_user+0x3f/0x140 kernel/signal.c:3387
 x64_setup_rt_frame+0x1e24/0x23e0 arch/x86/kernel/signal_64.c:194
 setup_rt_frame arch/x86/kernel/signal.c:250 [inline]
 handle_signal arch/x86/kernel/signal.c:294 [inline]
 arch_do_signal_or_restart+0x627/0xcb0 arch/x86/kernel/signal.c:339
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x5d/0x170 kernel/entry/common.c:218
 do_syscall_64+0xda/0x1e0 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was stored to memory at:
 copy_siginfo include/linux/signal.h:18 [inline]
 collect_signal kernel/signal.c:588 [inline]
 __dequeue_signal+0x501/0xad0 kernel/signal.c:617
 dequeue_signal+0x162/0xb30 kernel/signal.c:638
 get_signal+0xb42/0x2d00 kernel/signal.c:2798
 arch_do_signal_or_restart+0x53/0xcb0 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x5d/0x170 kernel/entry/common.c:218
 do_syscall_64+0xda/0x1e0 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was created at:
 slab_free_hook mm/slub.c:2268 [inline]
 slab_free mm/slub.c:4579 [inline]
 kmem_cache_free+0x290/0xdf0 mm/slub.c:4681
 __sigqueue_free kernel/signal.c:452 [inline]
 collect_signal kernel/signal.c:595 [inline]
 __dequeue_signal+0xa58/0xad0 kernel/signal.c:617
 dequeue_signal+0x162/0xb30 kernel/signal.c:638
 get_signal+0xb42/0x2d00 kernel/signal.c:2798
 arch_do_signal_or_restart+0x53/0xcb0 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x5d/0x170 kernel/entry/common.c:218
 do_syscall_64+0xda/0x1e0 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Bytes 12-15 of 48 are uninitialized
Memory access of size 48 starts at ffff888119bdfe20
Data copied to user address 00007f672f5d9bb0

CPU: 0 UID: 0 PID: 10359 Comm: syz.1.1075 Not tainted 6.12.0-rc7-syzkaller-00212-g4a5df3796467 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
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