diff options
| author | Anthony Krowiak <akrowiak@linux.ibm.com> | 2026-08-12 16:02:35 -0400 |
|---|---|---|
| committer | Christian Borntraeger <borntraeger@linux.ibm.com> | 2026-08-13 16:04:33 +0200 |
| commit | 5883528250be57fa92270459b33603ff52de0a91 (patch) | |
| tree | 6c88102937823073c0805c3e835282ff87f6928a | |
| parent | 7fa61c29850d05e40ca9ed41bfdf57673023f581 (diff) | |
s390/vfio-ap: Fix required lock not held during update of ap_matrix_mdev object
In the vfio_ap_mdev_cfg_add function, the apm_add, aqm_add and adm_add
fields of an ap_matrix_mdev object fields are modified while not holding
the matrix_dev->mdevs_lock. This lock must be held while making these
to guard against a race condition with another caller that may be
concurrently modifying these fields or any of the fields in the
matrix_mdev->matrix.
Fixes: eeb386aeb5b7c ("s390/vfio-ap: handle config changed and scan complete notification")
Cc: stable@vger.kernel.org
Signed-off-by: Anthony Krowiak <akrowiak@linux.ibm.com>
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
| -rw-r--r-- | drivers/s390/crypto/vfio_ap_ops.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c index a403d0f59122..d2f99079f619 100644 --- a/drivers/s390/crypto/vfio_ap_ops.c +++ b/drivers/s390/crypto/vfio_ap_ops.c @@ -2772,12 +2772,20 @@ static void vfio_ap_mdev_cfg_add(unsigned long *apm_add, unsigned long *aqm_add, * called. */ list_for_each_entry(matrix_mdev, &matrix_dev->mdev_list, node) { + /* + * The mdevs_lock must be held in order to access fields + * within matrix_mdev + */ + mutex_lock(&matrix_dev->mdevs_lock); + bitmap_and(matrix_mdev->apm_add, matrix_mdev->matrix.apm, apm_add, AP_DEVICES); bitmap_and(matrix_mdev->aqm_add, matrix_mdev->matrix.aqm, aqm_add, AP_DOMAINS); bitmap_and(matrix_mdev->adm_add, matrix_mdev->matrix.adm, adm_add, AP_DEVICES); + + mutex_unlock(&matrix_dev->mdevs_lock); } } |