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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:444 [inline]
 vmci_host_unlocked_ioctl+0x1e1d/0x5360 drivers/misc/vmw_vmci/vmci_host.c:938
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:907 [inline]
 __se_sys_ioctl+0x23c/0x400 fs/ioctl.c:893
 __x64_sys_ioctl+0x97/0xe0 fs/ioctl.c:893
 x64_sys_call+0x1ebe/0x3db0 arch/x86/include/generated/asm/syscalls_64.h:17
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was stored to memory at:
 kmemdup_noprof+0xb0/0x100 mm/util.c:139
 kmemdup_noprof 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+0x4524/0x5360 drivers/misc/vmw_vmci/vmci_host.c:934
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:907 [inline]
 __se_sys_ioctl+0x23c/0x400 fs/ioctl.c:893
 __x64_sys_ioctl+0x97/0xe0 fs/ioctl.c:893
 x64_sys_call+0x1ebe/0x3db0 arch/x86/include/generated/asm/syscalls_64.h:17
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

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 ffff888013ca72c0
Data copied to user address 000000000000a4bf

CPU: 1 UID: 0 PID: 6602 Comm: syz.0.16 Not tainted 6.16.0-rc2-syzkaller-00162-g41687a5c6f8b-dirty #0 PREEMPT(undef) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
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