18abda7a2d
The aux-domain attach/detach are not tracked, some data structures might
be used after free. This causes general protection faults when multiple
subdevices are created and assigned to a same guest machine:
| general protection fault, probably for non-canonical address 0xdead000000000100: 0000 [#1] SMP NOPTI
| RIP: 0010:intel_iommu_aux_detach_device+0x12a/0x1f0
| [...]
| Call Trace:
| iommu_aux_detach_device+0x24/0x70
| vfio_mdev_detach_domain+0x3b/0x60
| ? vfio_mdev_set_domain+0x50/0x50
| iommu_group_for_each_dev+0x4f/0x80
| vfio_iommu_detach_group.isra.0+0x22/0x30
| vfio_iommu_type1_detach_group.cold+0x71/0x211
| ? find_exported_symbol_in_section+0x4a/0xd0
| ? each_symbol_section+0x28/0x50
| __vfio_group_unset_container+0x4d/0x150
| vfio_group_try_dissolve_container+0x25/0x30
| vfio_group_put_external_user+0x13/0x20
| kvm_vfio_group_put_external_user+0x27/0x40 [kvm]
| kvm_vfio_destroy+0x45/0xb0 [kvm]
| kvm_put_kvm+0x1bb/0x2e0 [kvm]
| kvm_vm_release+0x22/0x30 [kvm]
| __fput+0xcc/0x260
| ____fput+0xe/0x10
| task_work_run+0x8f/0xb0
| do_exit+0x358/0xaf0
| ? wake_up_state+0x10/0x20
| ? signal_wake_up_state+0x1a/0x30
| do_group_exit+0x47/0xb0
| __x64_sys_exit_group+0x18/0x20
| do_syscall_64+0x57/0x1d0
| entry_SYSCALL_64_after_hwframe+0x44/0xa9
Fix the crash by tracking the subdevices when attaching and detaching
aux-domains.
Fixes:
|
||
|---|---|---|
| .. | ||
| debugfs.c | ||
| dmar.c | ||
| iommu.c | ||
| irq_remapping.c | ||
| Kconfig | ||
| Makefile | ||
| pasid.c | ||
| pasid.h | ||
| svm.c | ||
| trace.c | ||