The introduction of the capability chain rightly clamped the region indexes to the range of the capabilities itself, but neglected to do so for the existing read/write regions which should also be enforced. Fixes: db8e5d17ac03 ("vfio-ccw: add capabilities chain") Cc: stable@vger.kernel.org Cc: Cornelia Huck Signed-off-by: Eric Farman --- drivers/s390/cio/vfio_ccw_async.c | 16 ++++++++++++++++ drivers/s390/cio/vfio_ccw_chp.c | 15 +++++++++++++++ drivers/s390/cio/vfio_ccw_ops.c | 7 +++---- 3 files changed, 34 insertions(+), 4 deletions(-) diff --git a/drivers/s390/cio/vfio_ccw_async.c b/drivers/s390/cio/vfio_ccw_async.c index 420d89ba7f83..4aff0b58fa5d 100644 --- a/drivers/s390/cio/vfio_ccw_async.c +++ b/drivers/s390/cio/vfio_ccw_async.c @@ -8,6 +8,7 @@ */ #include +#include #include "vfio_ccw_private.h" @@ -24,11 +25,20 @@ static ssize_t vfio_ccw_async_region_read(struct vfio_ccw_private *private, return -EINVAL; mutex_lock(&private->io_mutex); + + if (i >= private->num_regions) { + ret = -EINVAL; + goto out_unlock; + } + + i = array_index_nospec(i, private->num_regions); region = private->region[i].data; if (copy_to_user(buf, (void *)region + pos, count)) ret = -EFAULT; else ret = count; + +out_unlock: mutex_unlock(&private->io_mutex); return ret; } @@ -48,6 +58,12 @@ static ssize_t vfio_ccw_async_region_write(struct vfio_ccw_private *private, if (!mutex_trylock(&private->io_mutex)) return -EAGAIN; + if (i >= private->num_regions) { + ret = -EINVAL; + goto out_unlock; + } + + i = array_index_nospec(i, private->num_regions); region = private->region[i].data; if (copy_from_user((void *)region + pos, buf, count)) { ret = -EFAULT; diff --git a/drivers/s390/cio/vfio_ccw_chp.c b/drivers/s390/cio/vfio_ccw_chp.c index 38c176cf6295..f3015132d4b5 100644 --- a/drivers/s390/cio/vfio_ccw_chp.c +++ b/drivers/s390/cio/vfio_ccw_chp.c @@ -9,6 +9,7 @@ */ #include +#include #include #include "vfio_ccw_private.h" @@ -26,6 +27,13 @@ static ssize_t vfio_ccw_schib_region_read(struct vfio_ccw_private *private, return -EINVAL; mutex_lock(&private->io_mutex); + + if (i >= private->num_regions) { + ret = -EINVAL; + goto out; + } + + i = array_index_nospec(i, private->num_regions); region = private->region[i].data; if (cio_update_schib(sch)) { @@ -97,6 +105,12 @@ static ssize_t vfio_ccw_crw_region_read(struct vfio_ccw_private *private, list_del(&crw->next); mutex_lock(&private->io_mutex); + if (i >= private->num_regions) { + ret = -EINVAL; + goto out; + } + + i = array_index_nospec(i, private->num_regions); region = private->region[i].data; if (crw) @@ -109,6 +123,7 @@ static ssize_t vfio_ccw_crw_region_read(struct vfio_ccw_private *private, region->crw = 0; +out: mutex_unlock(&private->io_mutex); kfree(crw); diff --git a/drivers/s390/cio/vfio_ccw_ops.c b/drivers/s390/cio/vfio_ccw_ops.c index 45ec722d25ea..032a1cdf4df7 100644 --- a/drivers/s390/cio/vfio_ccw_ops.c +++ b/drivers/s390/cio/vfio_ccw_ops.c @@ -243,6 +243,7 @@ static ssize_t vfio_ccw_mdev_read(struct vfio_device *vdev, return vfio_ccw_mdev_read_io_region(private, buf, count, ppos); default: index -= VFIO_CCW_NUM_REGIONS; + index = array_index_nospec(index, private->num_regions); return private->region[index].ops->read(private, buf, count, ppos); } @@ -295,6 +296,7 @@ static ssize_t vfio_ccw_mdev_write(struct vfio_device *vdev, return vfio_ccw_mdev_write_io_region(private, buf, count, ppos); default: index -= VFIO_CCW_NUM_REGIONS; + index = array_index_nospec(index, private->num_regions); return private->region[index].ops->write(private, buf, count, ppos); } @@ -338,11 +340,8 @@ static int vfio_ccw_mdev_ioctl_get_region_info(struct vfio_device *vdev, VFIO_CCW_NUM_REGIONS + private->num_regions) return -EINVAL; - info->index = array_index_nospec(info->index, - VFIO_CCW_NUM_REGIONS + - private->num_regions); - i = info->index - VFIO_CCW_NUM_REGIONS; + i = array_index_nospec(i, private->num_regions); info->offset = VFIO_CCW_INDEX_TO_OFFSET(info->index); info->size = private->region[i].size; -- 2.53.0