=====================================================
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:3362
 ptrace_request+0xfa6/0x36d0 kernel/ptrace.c:1049
 arch_ptrace+0x435/0x680 arch/x86/kernel/ptrace.c:848
 __do_sys_ptrace kernel/ptrace.c:1288 [inline]
 __se_sys_ptrace+0x2d8/0x750 kernel/ptrace.c:1261
 __x64_sys_ptrace+0xbd/0x110 kernel/ptrace.c:1261
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x1e0 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:18 [inline]
 ptrace_getsiginfo kernel/ptrace.c:688 [inline]
 ptrace_request+0xf32/0x36d0 kernel/ptrace.c:1047
 arch_ptrace+0x435/0x680 arch/x86/kernel/ptrace.c:848
 __do_sys_ptrace kernel/ptrace.c:1288 [inline]
 __se_sys_ptrace+0x2d8/0x750 kernel/ptrace.c:1261
 __x64_sys_ptrace+0xbd/0x110 kernel/ptrace.c:1261
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x1e0 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:18 [inline]
 collect_signal kernel/signal.c:586 [inline]
 __dequeue_signal+0x501/0xad0 kernel/signal.c:615
 dequeue_signal+0x14b/0xb10 kernel/signal.c:638
 get_signal+0xb4d/0x2d80 kernel/signal.c:2773
 arch_do_signal_or_restart+0x53/0xca0 arch/x86/kernel/signal.c:310
 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+0x5c/0x170 kernel/entry/common.c:212
 do_syscall_64+0xdc/0x1e0 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Uninit was created at:
 slab_free_hook mm/slub.c:2088 [inline]
 slab_free mm/slub.c:4299 [inline]
 kmem_cache_free+0x256/0xa40 mm/slub.c:4363
 __sigqueue_free kernel/signal.c:450 [inline]
 collect_signal kernel/signal.c:593 [inline]
 __dequeue_signal+0xa58/0xad0 kernel/signal.c:615
 dequeue_signal+0x14b/0xb10 kernel/signal.c:638
 signalfd_dequeue fs/signalfd.c:163 [inline]
 signalfd_read+0x1f7/0x10f0 fs/signalfd.c:217
 vfs_read+0x296/0xeb0 fs/read_write.c:474
 ksys_read+0x20f/0x4c0 fs/read_write.c:619
 __do_sys_read fs/read_write.c:629 [inline]
 __se_sys_read fs/read_write.c:627 [inline]
 __x64_sys_read+0x93/0xd0 fs/read_write.c:627
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x1e0 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 ffff88812638bc60
Data copied to user address 0000000001ba1af0

CPU: 0 PID: 5011 Comm: strace-static-x Not tainted 6.8.0-rc5-syzkaller-00297-gf2e367d6ad3b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
=====================================================