Re: [PATCH] iommu/vt-d: Fix oops due to out of scope access

Re: [PATCH] iommu/vt-d: Fix oops due to out of scope access

[Baolu Lu]

On 4/21/26 11:13, Zhenzhong Duan wrote:
> Below oops triggers when kill QEMU process:
> 
>    Oops: general protection fault, probably for non-canonical address 0x7fffffff844eaaa7: 0000 [#1] SMP NOPTI
>    Call Trace:
>     <TASK>
>     do_raw_spin_lock+0xaa/0xc0
>     _raw_spin_lock_irqsave+0x21/0x40
>     domain_remove_dev_pasid+0x52/0x160
>     intel_nested_set_dev_pasid+0x1b9/0x1e0
>     __iommu_set_group_pasid+0x56/0x120
>     pci_dev_reset_iommu_done+0xe3/0x180
>     pcie_flr+0x65/0x160
>     __pci_reset_function_locked+0x5b/0x120
>     vfio_pci_core_close_device+0x63/0xe0 [vfio_pci_core]
>     vfio_df_close+0x4f/0xa0
>     vfio_df_unbind_iommufd+0x2d/0x60
>     vfio_device_fops_release+0x3e/0x40
>     __fput+0xe5/0x2c0
>     task_work_run+0x58/0xa0
>     do_exit+0x2c8/0x600
>     do_group_exit+0x2f/0xa0
>     get_signal+0x863/0x8c0
>     arch_do_signal_or_restart+0x24/0x100
>     exit_to_user_mode_loop+0x87/0x380
>     do_syscall_64+0x2ff/0x11e0
>     entry_SYSCALL_64_after_hwframe+0x76/0x7e
> 
> The global static blocked domain is a dummy domain without corresponding
> dmar_domain structure, accessing beyond iommu_domain structure triggers
> oops easily. Fix it by return early in domain_remove_dev_pasid() like
> identity domain.
> 
> Fixes: 7d0c9da6c150 ("iommu/vt-d: Add set_dev_pasid callback for dma domain")
> Signed-off-by: Zhenzhong Duan<zhenzhong.duan@intel.com>
> ---
>   drivers/iommu/intel/iommu.c | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)

Queued for v7.1-rc. Thanks!