4.9-stable review patch. If anyone has any objections, please let me know.
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From: Jorgen Hansen jhansen@vmware.com
[ Upstream commit 11924ba5e671d6caef1516923e2bd8c72929a3fe ]
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 Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/misc/vmw_vmci/vmci_driver.c | 2 +- drivers/misc/vmw_vmci/vmci_resource.c | 3 ++- 2 files changed, 3 insertions(+), 2 deletions(-)
--- a/drivers/misc/vmw_vmci/vmci_driver.c +++ b/drivers/misc/vmw_vmci/vmci_driver.c @@ -113,5 +113,5 @@ module_exit(vmci_drv_exit);
MODULE_AUTHOR("VMware, Inc."); MODULE_DESCRIPTION("VMware Virtual Machine Communication Interface."); -MODULE_VERSION("1.1.5.0-k"); +MODULE_VERSION("1.1.6.0-k"); MODULE_LICENSE("GPL v2"); --- a/drivers/misc/vmw_vmci/vmci_resource.c +++ b/drivers/misc/vmw_vmci/vmci_resource.c @@ -56,7 +56,8 @@ static struct vmci_resource *vmci_resour
if (r->type == type && rid == handle.resource && - (cid == handle.context || cid == VMCI_INVALID_ID)) { + (cid == handle.context || cid == VMCI_INVALID_ID || + handle.context == VMCI_INVALID_ID)) { resource = r; break; }