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BUG: KMSAN: kernel-infoleak in instrument_copy_to_user include/linux/instrumented.h:114 [inline]
BUG: KMSAN: kernel-infoleak in _inline_copy_to_user include/linux/uaccess.h:205 [inline]
BUG: KMSAN: kernel-infoleak in _copy_to_user+0xcc/0x120 lib/usercopy.c:26
 instrument_copy_to_user include/linux/instrumented.h:114 [inline]
 _inline_copy_to_user include/linux/uaccess.h:205 [inline]
 _copy_to_user+0xcc/0x120 lib/usercopy.c:26
 copy_to_user include/linux/uaccess.h:236 [inline]
 copy_siginfo_to_user+0x3f/0x140 kernel/signal.c:3501
 x64_setup_rt_frame+0x1392/0x2590 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+0x63c/0xc00 arch/x86/kernel/signal.c:339
 __exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
 exit_to_user_mode_loop+0x118/0x1b70 kernel/entry/common.c:75
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
 do_syscall_64+0x1eb/0xf80 arch/x86/entry/syscall_64.c:100
 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:575 [inline]
 __dequeue_signal+0x4d6/0x970 kernel/signal.c:609
 dequeue_signal+0x1c0/0x840 kernel/signal.c:632
 get_signal+0xbf6/0x2a20 kernel/signal.c:2914
 arch_do_signal_or_restart+0x53/0xc00 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
 exit_to_user_mode_loop+0x118/0x1b70 kernel/entry/common.c:75
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
 do_syscall_64+0x1eb/0xf80 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was created at:
 __alloc_frozen_pages_noprof+0x421/0xab0 mm/page_alloc.c:5233
 alloc_pages_mpol+0x328/0x860 mm/mempolicy.c:2486
 alloc_frozen_pages_noprof+0xf7/0x200 mm/mempolicy.c:2557
 alloc_slab_page mm/slub.c:3075 [inline]
 allocate_slab+0x1ea/0x1710 mm/slub.c:3248
 new_slab mm/slub.c:3302 [inline]
 ___slab_alloc+0x12b2/0x3d10 mm/slub.c:4656
 __slab_alloc+0xa3/0x180 mm/slub.c:4779
 __slab_alloc_node mm/slub.c:4855 [inline]
 slab_alloc_node mm/slub.c:5251 [inline]
 kmem_cache_alloc_noprof+0xa25/0x1750 mm/slub.c:5270
 sigqueue_alloc kernel/signal.c:455 [inline]
 __send_signal_locked+0x27d/0x14c0 kernel/signal.c:1087
 send_signal_locked+0x738/0xb70 kernel/signal.c:1216
 do_send_sig_info+0x1ab/0x260 kernel/signal.c:1269
 group_send_sig_info+0xef/0x140 kernel/signal.c:1419
 do_bpf_send_signal+0xf8/0x270 kernel/trace/bpf_trace.c:813
 irq_work_single kernel/irq_work.c:221 [inline]
 irq_work_run_list kernel/irq_work.c:252 [inline]
 irq_work_run+0x1b3/0x780 kernel/irq_work.c:261
 __sysvec_irq_work+0x45/0x320 arch/x86/kernel/irq_work.c:22
 instr_sysvec_irq_work arch/x86/kernel/irq_work.c:17 [inline]
 sysvec_irq_work+0x7c/0x90 arch/x86/kernel/irq_work.c:17
 asm_sysvec_irq_work+0x1f/0x30 arch/x86/include/asm/idtentry.h:733

Bytes 12-15 of 48 are uninitialized
Memory access of size 48 starts at ffff888062a0fd00
Data copied to user address 00007ffc6ac5dcf0

CPU: 0 UID: 0 PID: 8598 Comm: syz.5.918 Not tainted syzkaller #0 PREEMPT(none) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
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