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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
 ptrace_request+0xfa6/0x36d0 kernel/ptrace.c:1066
 arch_ptrace+0x435/0x680 arch/x86/kernel/ptrace.c:848
 __do_sys_ptrace kernel/ptrace.c:1305 [inline]
 __se_sys_ptrace+0x2d8/0x750 kernel/ptrace.c:1278
 __x64_sys_ptrace+0xbd/0x110 kernel/ptrace.c:1278
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Uninit was stored to memory at:
 copy_siginfo include/linux/signal.h:17 [inline]
 ptrace_getsiginfo kernel/ptrace.c:705 [inline]
 ptrace_request+0xf32/0x36d0 kernel/ptrace.c:1064
 arch_ptrace+0x435/0x680 arch/x86/kernel/ptrace.c:848
 __do_sys_ptrace kernel/ptrace.c:1305 [inline]
 __se_sys_ptrace+0x2d8/0x750 kernel/ptrace.c:1278
 __x64_sys_ptrace+0xbd/0x110 kernel/ptrace.c:1278
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:83
 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+0xe8/0x320 kernel/entry/common.c:168
 exit_to_user_mode_prepare+0x163/0x220 kernel/entry/common.c:204
 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline]
 syscall_exit_to_user_mode+0x2a/0x140 kernel/entry/common.c:296
 do_syscall_64+0x50/0x110 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
 signalfd_dequeue fs/signalfd.c:163 [inline]
 signalfd_read+0x1f7/0x10f0 fs/signalfd.c:217
 vfs_read+0x367/0xe00 fs/read_write.c:468
 ksys_read+0x20f/0x4c0 fs/read_write.c:613
 __do_sys_read fs/read_write.c:623 [inline]
 __se_sys_read fs/read_write.c:621 [inline]
 __x64_sys_read+0x93/0xd0 fs/read_write.c:621
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Bytes 12-15 of 48 are uninitialized
Memory access of size 48 starts at ffff88812110fc80
Data copied to user address 0000000001a1b2a0

CPU: 0 PID: 5004 Comm: strace-static-x Not tainted 6.7.0-rc7-syzkaller-00003-gfbafc3e621c3 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
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