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BUG: KMSAN: kernel-infoleak in kmsan_copy_to_user+0x9c/0xb0 mm/kmsan/kmsan_hooks.c:249
CPU: 1 PID: 2560 Comm: syz-executor.5 Not tainted 5.10.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x21c/0x280 lib/dump_stack.c:118
 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:118
 kmsan_internal_check_memory+0x484/0x520 mm/kmsan/kmsan.c:437
 kmsan_copy_to_user+0x9c/0xb0 mm/kmsan/kmsan_hooks.c:249
 instrument_copy_to_user include/linux/instrumented.h:121 [inline]
 _copy_to_user+0x16e/0x240 lib/usercopy.c:33
 copy_to_user include/linux/uaccess.h:209 [inline]
 vmci_host_do_ctx_get_cpt_state drivers/misc/vmw_vmci/vmci_host.c:723 [inline]
 vmci_host_unlocked_ioctl+0x3486/0x59a0 drivers/misc/vmw_vmci/vmci_host.c:939
 vfs_ioctl fs/ioctl.c:48 [inline]
 __do_sys_ioctl fs/ioctl.c:753 [inline]
 __se_sys_ioctl+0x311/0x4d0 fs/ioctl.c:739
 __x64_sys_ioctl+0x4a/0x70 fs/ioctl.c:739
 do_syscall_64+0x9f/0x140 arch/x86/entry/common.c:48
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45e159
Code: 0d b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 db b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f487f440c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045e159
RDX: 0000000020001540 RSI: 00000000000007b1 RDI: 0000000000000003
RBP: 000000000119bfc0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000119bf8c
R13: 00000000016afb7f R14: 00007f487f4419c0 R15: 000000000119bf8c

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:121 [inline]
 kmsan_internal_poison_shadow+0x5c/0xf0 mm/kmsan/kmsan.c:104
 kmsan_slab_alloc+0x8d/0xe0 mm/kmsan/kmsan_hooks.c:76
 slab_alloc_node mm/slub.c:2906 [inline]
 slab_alloc mm/slub.c:2915 [inline]
 __kmalloc+0x2f0/0x530 mm/slub.c:3983
 kmalloc include/linux/slab.h:557 [inline]
 vmci_ctx_get_chkpt_doorbells drivers/misc/vmw_vmci/vmci_context.c:746 [inline]
 vmci_ctx_get_chkpt_state+0x6a0/0xf30 drivers/misc/vmw_vmci/vmci_context.c:798
 vmci_host_do_ctx_get_cpt_state drivers/misc/vmw_vmci/vmci_host.c:719 [inline]
 vmci_host_unlocked_ioctl+0x2e02/0x59a0 drivers/misc/vmw_vmci/vmci_host.c:939
 vfs_ioctl fs/ioctl.c:48 [inline]
 __do_sys_ioctl fs/ioctl.c:753 [inline]
 __se_sys_ioctl+0x311/0x4d0 fs/ioctl.c:739
 __x64_sys_ioctl+0x4a/0x70 fs/ioctl.c:739
 do_syscall_64+0x9f/0x140 arch/x86/entry/common.c:48
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Bytes 8-15 of 16 are uninitialized
Memory access of size 16 starts at ffff888120dce9d0
Data copied to user address 0000000020000540
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