Longpeng e4d58ac67e vdpa_sim: avoid putting an uninitialized iova_domain ... commit bb93ce4b15 upstream. The system will crash if we put an uninitialized iova_domain, this could happen when an error occurs before initializing the iova_domain in vdpasim_create(). BUG: kernel NULL pointer dereference, address: 0000000000000000 ... RIP: 0010:__cpuhp_state_remove_instance+0x96/0x1c0 ... Call Trace: <TASK> put_iova_domain+0x29/0x220 vdpasim_free+0xd1/0x120 [vdpa_sim] vdpa_release_dev+0x21/0x40 [vdpa] device_release+0x33/0x90 kobject_release+0x63/0x160 vdpasim_create+0x127/0x2a0 [vdpa_sim] vdpasim_net_dev_add+0x7d/0xfe [vdpa_sim_net] vdpa_nl_cmd_dev_add_set_doit+0xe1/0x1a0 [vdpa] genl_family_rcv_msg_doit+0x112/0x140 genl_rcv_msg+0xdf/0x1d0 ... So we must make sure the iova_domain is already initialized before put it. In addition, we may get the following warning in this case: WARNING: ... drivers/iommu/iova.c:344 iova_cache_put+0x58/0x70 So we must make sure the iova_cache_put() is invoked only if the iova_cache_get() is already invoked. Let's fix it together. Cc: stable@vger.kernel.org Fixes: 4080fc1067 ("vdpa_sim: use iova module to allocate IOVA addresses") Signed-off-by: Longpeng <longpeng2@huawei.com> Acked-by: Jason Wang <jasowang@redhat.com> Reviewed-by: Stefano Garzarella <sgarzare@redhat.com> Link: https://lore.kernel.org/r/20211124015215.119-1-longpeng2@huawei.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2021-12-01 09:04:55 +01:00
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Makefile	vdpa: add vdpa simulator for block device	2021-05-03 04:55:53 -04:00
vdpa_sim.c	vdpa_sim: avoid putting an uninitialized iova_domain	2021-12-01 09:04:55 +01:00
vdpa_sim.h	vdpa_sim: use iova module to allocate IOVA addresses	2021-05-03 04:55:52 -04:00
vdpa_sim_blk.c	vdpa_sim_blk: remove duplicate include of linux/blkdev.h	2021-07-03 04:50:50 -04:00
vdpa_sim_net.c	vdpa_sim: Skip typecasting from void*	2021-03-14 04:37:36 -04:00