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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:196 [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:196 [inline]
 _copy_to_user+0xcc/0x120 lib/usercopy.c:26
 copy_to_user include/linux/uaccess.h:225 [inline]
 vmci_host_do_receive_datagram drivers/misc/vmw_vmci/vmci_host.c:438 [inline]
 vmci_host_unlocked_ioctl+0x1e7e/0x5200 drivers/misc/vmw_vmci/vmci_host.c:932
 compat_ptr_ioctl+0x82/0xe0 fs/ioctl.c:944
 __do_compat_sys_ioctl fs/ioctl.c:1005 [inline]
 __se_compat_sys_ioctl fs/ioctl.c:948 [inline]
 __ia32_compat_sys_ioctl+0x7f9/0x1270 fs/ioctl.c:948
 ia32_sys_call+0x2d07/0x42c0 arch/x86/include/generated/asm/syscalls_32.h:55
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
 __do_fast_syscall_32+0xb0/0x150 arch/x86/entry/syscall_32.c:306
 do_fast_syscall_32+0x38/0x80 arch/x86/entry/syscall_32.c:331
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/syscall_32.c:369
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

Uninit was stored to memory at:
 kmemdup_noprof+0xb0/0x100 mm/util.c:139
 _Z14kmemdup_noprofPKvU25pass_dynamic_object_size0mj include/linux/fortify-string.h:765 [inline]
 dg_dispatch_as_host drivers/misc/vmw_vmci/vmci_datagram.c:272 [inline]
 vmci_datagram_dispatch+0x4eb/0x1560 drivers/misc/vmw_vmci/vmci_datagram.c:340
 ctx_fire_notification drivers/misc/vmw_vmci/vmci_context.c:257 [inline]
 ctx_free_ctx drivers/misc/vmw_vmci/vmci_context.c:435 [inline]
 kref_put include/linux/kref.h:65 [inline]
 vmci_ctx_put+0x88e/0x15d0 drivers/misc/vmw_vmci/vmci_context.c:497
 vmci_ctx_destroy+0x15d/0x250 drivers/misc/vmw_vmci/vmci_context.c:195
 vmci_host_do_init_context drivers/misc/vmw_vmci/vmci_host.c:341 [inline]
 vmci_host_unlocked_ioctl+0x4592/0x5200 drivers/misc/vmw_vmci/vmci_host.c:928
 compat_ptr_ioctl+0x82/0xe0 fs/ioctl.c:944
 __do_compat_sys_ioctl fs/ioctl.c:1005 [inline]
 __se_compat_sys_ioctl fs/ioctl.c:948 [inline]
 __ia32_compat_sys_ioctl+0x7f9/0x1270 fs/ioctl.c:948
 ia32_sys_call+0x2d07/0x42c0 arch/x86/include/generated/asm/syscalls_32.h:55
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
 __do_fast_syscall_32+0xb0/0x150 arch/x86/entry/syscall_32.c:306
 do_fast_syscall_32+0x38/0x80 arch/x86/entry/syscall_32.c:331
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/syscall_32.c:369
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

Local variable ev.i.i created at:
 ctx_fire_notification drivers/misc/vmw_vmci/vmci_context.c:248 [inline]
 ctx_free_ctx drivers/misc/vmw_vmci/vmci_context.c:435 [inline]
 kref_put include/linux/kref.h:65 [inline]
 vmci_ctx_put+0x76b/0x15d0 drivers/misc/vmw_vmci/vmci_context.c:497
 vmci_ctx_destroy+0x15d/0x250 drivers/misc/vmw_vmci/vmci_context.c:195

Bytes 28-31 of 40 are uninitialized
Memory access of size 40 starts at ffff888039a8ea00
Data copied to user address 000000000000a4bf

CPU: 0 UID: 0 PID: 15916 Comm: syz.7.2569 Not tainted 6.16.0-rc1-syzkaller-00239-g08215f5486ec #0 PREEMPT(undef) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
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