diff options
| author | Mike Christie <michael.christie@oracle.com> | 2023-03-20 21:06:18 -0500 |
|---|---|---|
| committer | Michael S. Tsirkin <mst@redhat.com> | 2023-04-04 11:01:58 -0400 |
| commit | e508efc3ae7e44eb3caf595a086bfd3824da5b9a (patch) | |
| tree | f203cdbff4a4eb68d4ffd551cbcde361ba3b5fa6 /drivers/vhost | |
| parent | 10805eb5d6d15fd4f61b05cc7aa269e12ab99848 (diff) | |
vhost-scsi: Fix vhost_scsi struct use after free
If vhost_scsi_setup_vq_cmds fails we leave the tpg->vhost_scsi pointer
set. If the device is freed and then the user unmaps the LUN, the call to
vhost_scsi_port_unlink -> vhost_scsi_hotunplug will see the that
tpg->vhost_scsi is still set and try to use it.
This has us clear the vhost_scsi pointer in the failure path. It also
has us take tv_tpg_mutex in this failure path, because tv_tpg_vhost_count
is accessed under this mutex in vhost_scsi_drop_nexus and in the future
we will want to serialize access to tpg->vhost_scsi with that mutex
instead of the vhost_scsi_mutex.
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Message-Id: <20230321020624.13323-2-michael.christie@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Diffstat (limited to 'drivers/vhost')
| -rw-r--r-- | drivers/vhost/scsi.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/vhost/scsi.c b/drivers/vhost/scsi.c index b244e7c0f514..5875241e1654 100644 --- a/drivers/vhost/scsi.c +++ b/drivers/vhost/scsi.c @@ -1658,7 +1658,10 @@ undepend: for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) { tpg = vs_tpg[i]; if (tpg) { + mutex_lock(&tpg->tv_tpg_mutex); + tpg->vhost_scsi = NULL; tpg->tv_tpg_vhost_count--; + mutex_unlock(&tpg->tv_tpg_mutex); target_undepend_item(&tpg->se_tpg.tpg_group.cg_item); } } |