Stefano Garzarella
2021-Nov-23 08:19 UTC
[PATCH] vdpa_sim: avoid putting an uninitialized iova_domain
On Mon, Nov 22, 2021 at 08:22:21PM +0800, Longpeng(Mike) wrote:>From: Longpeng <longpeng2 at huawei.com> > >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. > >Signed-off-by: Longpeng <longpeng2 at huawei.com> >--- > drivers/vdpa/vdpa_sim/vdpa_sim.c | 7 +++++-- > 1 file changed, 5 insertions(+), 2 deletions(-)Ooops, thanks for fixing this :-) With the Fixes tag as suggested: Reviewed-by: Stefano Garzarella <sgarzare at redhat.com>