| Message ID | 20210602133029.2864069-3-ming.lei@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | scsi: fix failure handling of alloc/add host | expand |
On 02/06/2021 14:30, Ming Lei wrote: > When scsi_add_host_with_dma() return failure, the caller will call > scsi_host_put(shost) to release everything allocated for this host > instance. So we can't free allocated stuff in scsi_add_host_with_dma(), > otherwise double free will be caused. > > Strictly speaking, these host resources allocation should have been > moved to scsi_host_alloc(), but the allocation may need driver's > info which can be built between calling scsi_host_alloc() and > scsi_add_host(), so just keep the allocations in > scsi_add_host_with_dma(). > > Fixes the problem by relying on host device's release handler to > release everything. > > Cc: Bart Van Assche<bvanassche@acm.org> > Cc: John Garry<john.garry@huawei.com> > Cc: Hannes Reinecke<hare@suse.de> > Signed-off-by: Ming Lei<ming.lei@redhat.com> Reviewed-by: John Garry <john.garry@huawei.com>
On 6/2/21 3:30 PM, Ming Lei wrote: > When scsi_add_host_with_dma() return failure, the caller will call > scsi_host_put(shost) to release everything allocated for this host > instance. So we can't free allocated stuff in scsi_add_host_with_dma(), > otherwise double free will be caused. > > Strictly speaking, these host resources allocation should have been > moved to scsi_host_alloc(), but the allocation may need driver's > info which can be built between calling scsi_host_alloc() and > scsi_add_host(), so just keep the allocations in > scsi_add_host_with_dma(). > > Fixes the problem by relying on host device's release handler to > release everything. > > Cc: Bart Van Assche <bvanassche@acm.org> > Cc: John Garry <john.garry@huawei.com> > Cc: Hannes Reinecke <hare@suse.de> > Signed-off-by: Ming Lei <ming.lei@redhat.com> > --- > drivers/scsi/hosts.c | 14 ++++++-------- > 1 file changed, 6 insertions(+), 8 deletions(-) > Reviewed-by: Hannes Reinecke <hare@suse.de> Cheers, Hannes -- Dr. Hannes Reinecke Kernel Storage Architect hare@suse.de +49 911 74053 688 SUSE Software Solutions Germany GmbH, 90409 Nürnberg GF: F. Imendörffer, HRB 36809 (AG Nürnberg)
diff --git a/drivers/scsi/hosts.c b/drivers/scsi/hosts.c index 25cf76e73595..796736e47764 100644 --- a/drivers/scsi/hosts.c +++ b/drivers/scsi/hosts.c @@ -281,23 +281,22 @@ int scsi_add_host_with_dma(struct Scsi_Host *shost, struct device *dev, if (!shost->work_q) { error = -EINVAL; - goto out_free_shost_data; + goto out_del_dev; } } error = scsi_sysfs_add_host(shost); if (error) - goto out_destroy_host; + goto out_del_dev; scsi_proc_host_add(shost); scsi_autopm_put_host(shost); return error; - out_destroy_host: - if (shost->work_q) - destroy_workqueue(shost->work_q); - out_free_shost_data: - kfree(shost->shost_data); + /* + * any host allocation in this function will be freed in + * scsi_host_dev_release, so don't free them in the failure path + */ out_del_dev: device_del(&shost->shost_dev); out_del_gendev: @@ -307,7 +306,6 @@ int scsi_add_host_with_dma(struct Scsi_Host *shost, struct device *dev, pm_runtime_disable(&shost->shost_gendev); pm_runtime_set_suspended(&shost->shost_gendev); pm_runtime_put_noidle(&shost->shost_gendev); - scsi_mq_destroy_tags(shost); fail: return error; }
When scsi_add_host_with_dma() return failure, the caller will call scsi_host_put(shost) to release everything allocated for this host instance. So we can't free allocated stuff in scsi_add_host_with_dma(), otherwise double free will be caused. Strictly speaking, these host resources allocation should have been moved to scsi_host_alloc(), but the allocation may need driver's info which can be built between calling scsi_host_alloc() and scsi_add_host(), so just keep the allocations in scsi_add_host_with_dma(). Fixes the problem by relying on host device's release handler to release everything. Cc: Bart Van Assche <bvanassche@acm.org> Cc: John Garry <john.garry@huawei.com> Cc: Hannes Reinecke <hare@suse.de> Signed-off-by: Ming Lei <ming.lei@redhat.com> --- drivers/scsi/hosts.c | 14 ++++++-------- 1 file changed, 6 insertions(+), 8 deletions(-)