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| author | Lu Baolu <baolu.lu@linux.intel.com> | 2025-07-23 15:20:45 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-08-15 16:38:51 +0200 |
| commit | c68332b7ee893292bba6e87d31ef2080c066c65d (patch) | |
| tree | 97a580f5e1d9c65e2649bb06f5b30324a9ca6d45 /drivers/iommu | |
| parent | f2e249b5ffd749e0766cd88f8e1a952b2b9a940d (diff) | |
| download | linux-c68332b7ee893292bba6e87d31ef2080c066c65d.tar.gz linux-c68332b7ee893292bba6e87d31ef2080c066c65d.tar.bz2 linux-c68332b7ee893292bba6e87d31ef2080c066c65d.zip | |
iommu/vt-d: Fix UAF on sva unbind with pending IOPFs
[ Upstream commit f0b9d31c6edd50a6207489cd1bd4ddac814b9cd2 ]
Commit 17fce9d2336d ("iommu/vt-d: Put iopf enablement in domain attach
path") disables IOPF on device by removing the device from its IOMMU's
IOPF queue when the last IOPF-capable domain is detached from the device.
Unfortunately, it did this in a wrong place where there are still pending
IOPFs. As a result, a use-after-free error is potentially triggered and
eventually a kernel panic with a kernel trace similar to the following:
refcount_t: underflow; use-after-free.
WARNING: CPU: 3 PID: 313 at lib/refcount.c:28 refcount_warn_saturate+0xd8/0xe0
Workqueue: iopf_queue/dmar0-iopfq iommu_sva_handle_iopf
Call Trace:
<TASK>
iopf_free_group+0xe/0x20
process_one_work+0x197/0x3d0
worker_thread+0x23a/0x350
? rescuer_thread+0x4a0/0x4a0
kthread+0xf8/0x230
? finish_task_switch.isra.0+0x81/0x260
? kthreads_online_cpu+0x110/0x110
? kthreads_online_cpu+0x110/0x110
ret_from_fork+0x13b/0x170
? kthreads_online_cpu+0x110/0x110
ret_from_fork_asm+0x11/0x20
</TASK>
---[ end trace 0000000000000000 ]---
The intel_pasid_tear_down_entry() function is responsible for blocking
hardware from generating new page faults and flushing all in-flight
ones. Therefore, moving iopf_for_domain_remove() after this function
should resolve this.
Fixes: 17fce9d2336d ("iommu/vt-d: Put iopf enablement in domain attach path")
Reported-by: Ethan Milon <ethan.milon@eviden.com>
Closes: https://lore.kernel.org/r/e8b37f3e-8539-40d4-8993-43a1f3ffe5aa@eviden.com
Suggested-by: Ethan Milon <ethan.milon@eviden.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20250723072045.1853328-1-baolu.lu@linux.intel.com
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'drivers/iommu')
| -rw-r--r-- | drivers/iommu/intel/iommu.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c index 72b477911fdb..c0be0b64e4c7 100644 --- a/drivers/iommu/intel/iommu.c +++ b/drivers/iommu/intel/iommu.c @@ -3999,8 +3999,8 @@ static int blocking_domain_set_dev_pasid(struct iommu_domain *domain, { struct device_domain_info *info = dev_iommu_priv_get(dev); - iopf_for_domain_remove(old, dev); intel_pasid_tear_down_entry(info->iommu, dev, pasid, false); + iopf_for_domain_remove(old, dev); domain_remove_dev_pasid(old, dev, pasid); return 0; |