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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:187 [inline]
BUG: KMSAN: kernel-infoleak-after-free in _copy_to_user+0xbc/0x110 lib/usercopy.c:26
 instrument_copy_to_user include/linux/instrumented.h:114 [inline]
 _inline_copy_to_user include/linux/uaccess.h:187 [inline]
 _copy_to_user+0xbc/0x110 lib/usercopy.c:26
 copy_to_user include/linux/uaccess.h:216 [inline]
 copy_siginfo_to_user+0x40/0x130 kernel/signal.c:3386
 x64_setup_rt_frame+0x1e74/0x2460 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:587 [inline]
 __dequeue_signal+0x501/0xad0 kernel/signal.c:616
 dequeue_signal+0x162/0xb30 kernel/signal.c:637
 get_signal+0xb42/0x2d00 kernel/signal.c:2797
 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:451 [inline]
 collect_signal kernel/signal.c:594 [inline]
 __dequeue_signal+0xa58/0xad0 kernel/signal.c:616
 dequeue_signal+0x162/0xb30 kernel/signal.c:637
 get_signal+0xb42/0x2d00 kernel/signal.c:2797
 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]
 irqentry_exit_to_user_mode+0xac/0x160 kernel/entry/common.c:231
 irqentry_exit+0x16/0x60 kernel/entry/common.c:334
 exc_page_fault+0x526/0x700 arch/x86/mm/fault.c:1542
 asm_exc_page_fault+0x2b/0x30 arch/x86/include/asm/idtentry.h:623

Bytes 12-15 of 48 are uninitialized
Memory access of size 48 starts at ffff8880454c7e20
Data copied to user address 00007f5998e8ebb0

CPU: 1 UID: 0 PID: 7237 Comm: syz.2.846 Not tainted 6.12.0-rc3-syzkaller-00389-g3d5ad2d4eca3 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
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