crypto: qat - zero the VF migration state buffer on save

The QAT VF migration state buffer is allocated with kmalloc(), while
qat_vf_save_state() exposes all state_size bytes to userspace. The state
manager writes only the serialized sections, leaving the unused tail
unchanged. The first save can therefore disclose stale heap contents,
and subsequent saves can disclose data left by an earlier migration.

Zero the whole buffer before writing the setup data. Once the setup data
is present, preserve it and zero the remaining state area before each
state save.

Fixes: f0bbfc391a ("crypto: qat - implement interface for live migration")
Cc: stable@vger.kernel.org
Assisted-by: Claude:claude-fable-5
Signed-off-by: Karl Mehltretter <kmehltretter@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This commit is contained in:
Karl Mehltretter 2026-09-19 07:49:34 +02:00 committed by Herbert Xu
parent 360094ceb2
commit 5d504e6551

View File

@ -837,6 +837,9 @@ static int adf_gen4_vfmig_save_state(struct qat_mig_dev *mdev)
return ret;
}
memset(mdev->state + mdev->setup_size, 0,
mdev->state_size - mdev->setup_size);
adf_mstate_mgr_init(vfmig->mstate_mgr, mdev->state + mdev->setup_size,
mdev->state_size - mdev->setup_size);
if (!adf_mstate_preamble_add(vfmig->mstate_mgr))
@ -934,6 +937,8 @@ static int adf_gen4_vfmig_save_setup(struct qat_mig_dev *mdev)
if (mdev->setup_size)
return 0;
memset(mdev->state, 0, mdev->state_size);
adf_mstate_mgr_init(vfmig->mstate_mgr, mdev->state, mdev->state_size);
if (!adf_mstate_preamble_add(vfmig->mstate_mgr))
return -EINVAL;