tree ade571c3bcbee5264420e02b2e03830e2ad26802
parent 018d52e8b589206149be6a929f418379d5c7102d
author Jorgen Hansen <jhansen@vmware.com> 1537515065 -0700
committer Greg Kroah-Hartman <gregkh@linuxfoundation.org> 1538519770 -0700

VMCI: Resource wildcard match fixed

When adding a VMCI resource, the check for an existing entry
would ignore that the new entry could be a wildcard. This could
result in multiple resource entries that would match a given
handle. One disastrous outcome of this is that the
refcounting used to ensure that delayed callbacks for VMCI
datagrams have run before the datagram is destroyed can be
wrong, since the refcount could be increased on the duplicate
entry. This in turn leads to a use after free bug. This issue
was discovered by Hangbin Liu using KASAN and syzkaller.

Fixes: bc63dedb7d46 ("VMCI: resource object implementation")
Reported-by: Hangbin Liu <liuhangbin@gmail.com>
Reviewed-by: Adit Ranadive <aditr@vmware.com>
Reviewed-by: Vishnu Dasa <vdasa@vmware.com>
Signed-off-by: Jorgen Hansen <jhansen@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>