CVE-2022-49788

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> misc/vmw_vmci: fix an infoleak in vmci_host_do_receive_datagram()<br /> <br /> `struct vmci_event_qp` allocated by qp_notify_peer() contains padding,<br /> which may carry uninitialized data to the userspace, as observed by<br /> KMSAN:<br /> <br /> BUG: KMSAN: kernel-infoleak in instrument_copy_to_user ./include/linux/instrumented.h:121<br /> instrument_copy_to_user ./include/linux/instrumented.h:121<br /> _copy_to_user+0x5f/0xb0 lib/usercopy.c:33<br /> copy_to_user ./include/linux/uaccess.h:169<br /> vmci_host_do_receive_datagram drivers/misc/vmw_vmci/vmci_host.c:431<br /> vmci_host_unlocked_ioctl+0x33d/0x43d0 drivers/misc/vmw_vmci/vmci_host.c:925<br /> vfs_ioctl fs/ioctl.c:51<br /> ...<br /> <br /> Uninit was stored to memory at:<br /> kmemdup+0x74/0xb0 mm/util.c:131<br /> dg_dispatch_as_host drivers/misc/vmw_vmci/vmci_datagram.c:271<br /> vmci_datagram_dispatch+0x4f8/0xfc0 drivers/misc/vmw_vmci/vmci_datagram.c:339<br /> qp_notify_peer+0x19a/0x290 drivers/misc/vmw_vmci/vmci_queue_pair.c:1479<br /> qp_broker_attach drivers/misc/vmw_vmci/vmci_queue_pair.c:1662<br /> qp_broker_alloc+0x2977/0x2f30 drivers/misc/vmw_vmci/vmci_queue_pair.c:1750<br /> vmci_qp_broker_alloc+0x96/0xd0 drivers/misc/vmw_vmci/vmci_queue_pair.c:1940<br /> vmci_host_do_alloc_queuepair drivers/misc/vmw_vmci/vmci_host.c:488<br /> vmci_host_unlocked_ioctl+0x24fd/0x43d0 drivers/misc/vmw_vmci/vmci_host.c:927<br /> ...<br /> <br /> Local variable ev created at:<br /> qp_notify_peer+0x54/0x290 drivers/misc/vmw_vmci/vmci_queue_pair.c:1456<br /> qp_broker_attach drivers/misc/vmw_vmci/vmci_queue_pair.c:1662<br /> qp_broker_alloc+0x2977/0x2f30 drivers/misc/vmw_vmci/vmci_queue_pair.c:1750<br /> <br /> Bytes 28-31 of 48 are uninitialized<br /> Memory access of size 48 starts at ffff888035155e00<br /> Data copied to user address 0000000020000100<br /> <br /> Use memset() to prevent the infoleaks.<br /> <br /> Also speculatively fix qp_notify_peer_local(), which may suffer from the<br /> same problem.