| Message ID | 1417082643-23907-1-git-send-email-jasowang@redhat.com |
|---|---|
| State | New |
| Headers | show |
On Thu, 27 Nov 2014, Jason Wang wrote: > virtio_net_handle_ctrl() and other functions that process control vq > request call iov_discard_front() which will shorten the iov. This will > lead unmapping in virtqueue_push() leaks mapping. > > Fixes this by keeping the original iov untouched and using a temp variable > in those functions. > > Cc: Wen Congyang <wency@cn.fujitsu.com> > Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com> > Cc: qemu-stable@nongnu.org > Signed-off-by: Jason Wang <jasowang@redhat.com> Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> > Changes from V1: > - Use g_memdup() to simplify codes > --- > hw/net/virtio-net.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c > index 9b88775..e574bd4 100644 > --- a/hw/net/virtio-net.c > +++ b/hw/net/virtio-net.c > @@ -798,7 +798,7 @@ static void virtio_net_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq) > virtio_net_ctrl_ack status = VIRTIO_NET_ERR; > VirtQueueElement elem; > size_t s; > - struct iovec *iov; > + struct iovec *iov, *iov2; > unsigned int iov_cnt; > > while (virtqueue_pop(vq, &elem)) { > @@ -808,8 +808,8 @@ static void virtio_net_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq) > exit(1); > } > > - iov = elem.out_sg; > iov_cnt = elem.out_num; > + iov2 = iov = g_memdup(elem.out_sg, sizeof(struct iovec) * elem.out_num); > s = iov_to_buf(iov, iov_cnt, 0, &ctrl, sizeof(ctrl)); > iov_discard_front(&iov, &iov_cnt, sizeof(ctrl)); > if (s != sizeof(ctrl)) { > @@ -833,6 +833,7 @@ static void virtio_net_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq) > > virtqueue_push(vq, &elem, sizeof(status)); > virtio_notify(vdev, vq); > + g_free(iov2); > } > } > > -- > 1.9.1 >
On Thu, 11/27 18:04, Jason Wang wrote: > virtio_net_handle_ctrl() and other functions that process control vq > request call iov_discard_front() which will shorten the iov. This will > lead unmapping in virtqueue_push() leaks mapping. > > Fixes this by keeping the original iov untouched and using a temp variable > in those functions. > > Cc: Wen Congyang <wency@cn.fujitsu.com> > Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com> > Cc: qemu-stable@nongnu.org > Signed-off-by: Jason Wang <jasowang@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> > --- > Changes from V1: > - Use g_memdup() to simplify codes > --- > hw/net/virtio-net.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c > index 9b88775..e574bd4 100644 > --- a/hw/net/virtio-net.c > +++ b/hw/net/virtio-net.c > @@ -798,7 +798,7 @@ static void virtio_net_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq) > virtio_net_ctrl_ack status = VIRTIO_NET_ERR; > VirtQueueElement elem; > size_t s; > - struct iovec *iov; > + struct iovec *iov, *iov2; > unsigned int iov_cnt; > > while (virtqueue_pop(vq, &elem)) { > @@ -808,8 +808,8 @@ static void virtio_net_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq) > exit(1); > } > > - iov = elem.out_sg; > iov_cnt = elem.out_num; > + iov2 = iov = g_memdup(elem.out_sg, sizeof(struct iovec) * elem.out_num); > s = iov_to_buf(iov, iov_cnt, 0, &ctrl, sizeof(ctrl)); > iov_discard_front(&iov, &iov_cnt, sizeof(ctrl)); > if (s != sizeof(ctrl)) { > @@ -833,6 +833,7 @@ static void virtio_net_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq) > > virtqueue_push(vq, &elem, sizeof(status)); > virtio_notify(vdev, vq); > + g_free(iov2); > } > } > > -- > 1.9.1 >
On Thu, Nov 27, 2014 at 06:04:03PM +0800, Jason Wang wrote: > virtio_net_handle_ctrl() and other functions that process control vq > request call iov_discard_front() which will shorten the iov. This will > lead unmapping in virtqueue_push() leaks mapping. > > Fixes this by keeping the original iov untouched and using a temp variable > in those functions. > > Cc: Wen Congyang <wency@cn.fujitsu.com> > Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com> > Cc: qemu-stable@nongnu.org > Signed-off-by: Jason Wang <jasowang@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Peter, can you pick this up or do you want a pull request? > --- > Changes from V1: > - Use g_memdup() to simplify codes > --- > hw/net/virtio-net.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c > index 9b88775..e574bd4 100644 > --- a/hw/net/virtio-net.c > +++ b/hw/net/virtio-net.c > @@ -798,7 +798,7 @@ static void virtio_net_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq) > virtio_net_ctrl_ack status = VIRTIO_NET_ERR; > VirtQueueElement elem; > size_t s; > - struct iovec *iov; > + struct iovec *iov, *iov2; > unsigned int iov_cnt; > > while (virtqueue_pop(vq, &elem)) { > @@ -808,8 +808,8 @@ static void virtio_net_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq) > exit(1); > } > > - iov = elem.out_sg; > iov_cnt = elem.out_num; > + iov2 = iov = g_memdup(elem.out_sg, sizeof(struct iovec) * elem.out_num); > s = iov_to_buf(iov, iov_cnt, 0, &ctrl, sizeof(ctrl)); > iov_discard_front(&iov, &iov_cnt, sizeof(ctrl)); > if (s != sizeof(ctrl)) { > @@ -833,6 +833,7 @@ static void virtio_net_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq) > > virtqueue_push(vq, &elem, sizeof(status)); > virtio_notify(vdev, vq); > + g_free(iov2); > } > } > > -- > 1.9.1
On 27 November 2014 at 12:33, Michael S. Tsirkin <mst@redhat.com> wrote: > On Thu, Nov 27, 2014 at 06:04:03PM +0800, Jason Wang wrote: >> virtio_net_handle_ctrl() and other functions that process control vq >> request call iov_discard_front() which will shorten the iov. This will >> lead unmapping in virtqueue_push() leaks mapping. >> >> Fixes this by keeping the original iov untouched and using a temp variable >> in those functions. >> >> Cc: Wen Congyang <wency@cn.fujitsu.com> >> Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com> >> Cc: qemu-stable@nongnu.org >> Signed-off-by: Jason Wang <jasowang@redhat.com> > > Reviewed-by: Michael S. Tsirkin <mst@redhat.com> > > Peter, can you pick this up or do you want a pull request? I can pick it up. I was waiting a bit to check that everybody was happy that this is the correct way to fix the bug and the patch is ok... -- PMM
Konrad, I think we should have this fix in 4.5: without it vif=[ 'model=virtio-net' ] crashes QEMU. On Thu, 27 Nov 2014, Peter Maydell wrote: > On 27 November 2014 at 12:33, Michael S. Tsirkin <mst@redhat.com> wrote: > > On Thu, Nov 27, 2014 at 06:04:03PM +0800, Jason Wang wrote: > >> virtio_net_handle_ctrl() and other functions that process control vq > >> request call iov_discard_front() which will shorten the iov. This will > >> lead unmapping in virtqueue_push() leaks mapping. > >> > >> Fixes this by keeping the original iov untouched and using a temp variable > >> in those functions. > >> > >> Cc: Wen Congyang <wency@cn.fujitsu.com> > >> Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com> > >> Cc: qemu-stable@nongnu.org > >> Signed-off-by: Jason Wang <jasowang@redhat.com> > > > > Reviewed-by: Michael S. Tsirkin <mst@redhat.com> > > > > Peter, can you pick this up or do you want a pull request? > > I can pick it up. I was waiting a bit to check that everybody > was happy that this is the correct way to fix the bug and the > patch is ok...
On 27 November 2014 at 12:42, Peter Maydell <peter.maydell@linaro.org> wrote: > On 27 November 2014 at 12:33, Michael S. Tsirkin <mst@redhat.com> wrote: >> On Thu, Nov 27, 2014 at 06:04:03PM +0800, Jason Wang wrote: >>> virtio_net_handle_ctrl() and other functions that process control vq >>> request call iov_discard_front() which will shorten the iov. This will >>> lead unmapping in virtqueue_push() leaks mapping. >>> >>> Fixes this by keeping the original iov untouched and using a temp variable >>> in those functions. >>> >>> Cc: Wen Congyang <wency@cn.fujitsu.com> >>> Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com> >>> Cc: qemu-stable@nongnu.org >>> Signed-off-by: Jason Wang <jasowang@redhat.com> >> >> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> >> >> Peter, can you pick this up or do you want a pull request? > > I can pick it up. I was waiting a bit to check that everybody > was happy that this is the correct way to fix the bug and the > patch is ok... ...but discussing this with Stefan H on IRC we realised that the same issue also (at least potentially) affects virtio-blk, which suggests that we should fix this by making the core virtio code cope with backends which modify the sglists. -- PMM
On Thu, Nov 27, 2014 at 02:09:06PM +0000, Peter Maydell wrote: > On 27 November 2014 at 12:42, Peter Maydell <peter.maydell@linaro.org> wrote: > > On 27 November 2014 at 12:33, Michael S. Tsirkin <mst@redhat.com> wrote: > >> On Thu, Nov 27, 2014 at 06:04:03PM +0800, Jason Wang wrote: > >>> virtio_net_handle_ctrl() and other functions that process control vq > >>> request call iov_discard_front() which will shorten the iov. This will > >>> lead unmapping in virtqueue_push() leaks mapping. > >>> > >>> Fixes this by keeping the original iov untouched and using a temp variable > >>> in those functions. > >>> > >>> Cc: Wen Congyang <wency@cn.fujitsu.com> > >>> Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com> > >>> Cc: qemu-stable@nongnu.org > >>> Signed-off-by: Jason Wang <jasowang@redhat.com> > >> > >> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> > >> > >> Peter, can you pick this up or do you want a pull request? > > > > I can pick it up. I was waiting a bit to check that everybody > > was happy that this is the correct way to fix the bug and the > > patch is ok... > > ...but discussing this with Stefan H on IRC we realised that the same > issue also (at least potentially) affects virtio-blk, which suggests > that we should fix this by making the core virtio code cope with > backends which modify the sglists. > > -- PMM Okay, but this does not sound like 2.2 material to me.
On Thu, 27 Nov 2014, Peter Maydell wrote: > On 27 November 2014 at 12:42, Peter Maydell <peter.maydell@linaro.org> wrote: > > On 27 November 2014 at 12:33, Michael S. Tsirkin <mst@redhat.com> wrote: > >> On Thu, Nov 27, 2014 at 06:04:03PM +0800, Jason Wang wrote: > >>> virtio_net_handle_ctrl() and other functions that process control vq > >>> request call iov_discard_front() which will shorten the iov. This will > >>> lead unmapping in virtqueue_push() leaks mapping. > >>> > >>> Fixes this by keeping the original iov untouched and using a temp variable > >>> in those functions. > >>> > >>> Cc: Wen Congyang <wency@cn.fujitsu.com> > >>> Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com> > >>> Cc: qemu-stable@nongnu.org > >>> Signed-off-by: Jason Wang <jasowang@redhat.com> > >> > >> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> > >> > >> Peter, can you pick this up or do you want a pull request? > > > > I can pick it up. I was waiting a bit to check that everybody > > was happy that this is the correct way to fix the bug and the > > patch is ok... > > ...but discussing this with Stefan H on IRC we realised that the same > issue also (at least potentially) affects virtio-blk, which suggests > that we should fix this by making the core virtio code cope with > backends which modify the sglists. I think that a similar patch could be produced against hw/block/virtio-blk.c:virtio_blk_handle_request Alternatively my series would help by introducing virtqueue_unmap_sg and moving it out of virtqueue_fill. We could call virtqueue_unmap_sg from the drivers (instead of calling it from virtqueue_push) and that would solve the issue.
On Thu, Nov 27, 2014 at 02:54:47PM +0000, Stefano Stabellini wrote: > On Thu, 27 Nov 2014, Peter Maydell wrote: > > On 27 November 2014 at 12:42, Peter Maydell <peter.maydell@linaro.org> wrote: > > > On 27 November 2014 at 12:33, Michael S. Tsirkin <mst@redhat.com> wrote: > > >> On Thu, Nov 27, 2014 at 06:04:03PM +0800, Jason Wang wrote: > > >>> virtio_net_handle_ctrl() and other functions that process control vq > > >>> request call iov_discard_front() which will shorten the iov. This will > > >>> lead unmapping in virtqueue_push() leaks mapping. > > >>> > > >>> Fixes this by keeping the original iov untouched and using a temp variable > > >>> in those functions. > > >>> > > >>> Cc: Wen Congyang <wency@cn.fujitsu.com> > > >>> Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com> > > >>> Cc: qemu-stable@nongnu.org > > >>> Signed-off-by: Jason Wang <jasowang@redhat.com> > > >> > > >> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> > > >> > > >> Peter, can you pick this up or do you want a pull request? > > > > > > I can pick it up. I was waiting a bit to check that everybody > > > was happy that this is the correct way to fix the bug and the > > > patch is ok... > > > > ...but discussing this with Stefan H on IRC we realised that the same > > issue also (at least potentially) affects virtio-blk, which suggests > > that we should fix this by making the core virtio code cope with > > backends which modify the sglists. > > I think that a similar patch could be produced against > hw/block/virtio-blk.c:virtio_blk_handle_request Hmm, this is a data path operation. Adding malloc/free calls there will slow things down measureably. > Alternatively my series would help by introducing virtqueue_unmap_sg and > moving it out of virtqueue_fill. We could call virtqueue_unmap_sg from > the drivers (instead of calling it from virtqueue_push) and that would > solve the issue.
On Thu, Nov 27, 2014 at 02:09:06PM +0000, Peter Maydell wrote: > On 27 November 2014 at 12:42, Peter Maydell <peter.maydell@linaro.org> wrote: > > On 27 November 2014 at 12:33, Michael S. Tsirkin <mst@redhat.com> wrote: > >> On Thu, Nov 27, 2014 at 06:04:03PM +0800, Jason Wang wrote: > >>> virtio_net_handle_ctrl() and other functions that process control vq > >>> request call iov_discard_front() which will shorten the iov. This will > >>> lead unmapping in virtqueue_push() leaks mapping. > >>> > >>> Fixes this by keeping the original iov untouched and using a temp variable > >>> in those functions. > >>> > >>> Cc: Wen Congyang <wency@cn.fujitsu.com> > >>> Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com> > >>> Cc: qemu-stable@nongnu.org > >>> Signed-off-by: Jason Wang <jasowang@redhat.com> > >> > >> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> > >> > >> Peter, can you pick this up or do you want a pull request? > > > > I can pick it up. I was waiting a bit to check that everybody > > was happy that this is the correct way to fix the bug and the > > patch is ok... > > ...but discussing this with Stefan H on IRC we realised that the same > issue also (at least potentially) affects virtio-blk, which suggests > that we should fix this by making the core virtio code cope with > backends which modify the sglists. > > -- PMM I just sent a minimal fix for virtio blk. This way core rework can wait for 2.3.
On 27 November 2014 at 10:04, Jason Wang <jasowang@redhat.com> wrote: > virtio_net_handle_ctrl() and other functions that process control vq > request call iov_discard_front() which will shorten the iov. This will > lead unmapping in virtqueue_push() leaks mapping. > > Fixes this by keeping the original iov untouched and using a temp variable > in those functions. > > Cc: Wen Congyang <wency@cn.fujitsu.com> > Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com> > Cc: qemu-stable@nongnu.org > Signed-off-by: Jason Wang <jasowang@redhat.com> > --- > Changes from V1: > - Use g_memdup() to simplify codes > --- > hw/net/virtio-net.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) Applied to master, thanks. -- PMM
diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c index 9b88775..e574bd4 100644 --- a/hw/net/virtio-net.c +++ b/hw/net/virtio-net.c @@ -798,7 +798,7 @@ static void virtio_net_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq) virtio_net_ctrl_ack status = VIRTIO_NET_ERR; VirtQueueElement elem; size_t s; - struct iovec *iov; + struct iovec *iov, *iov2; unsigned int iov_cnt; while (virtqueue_pop(vq, &elem)) { @@ -808,8 +808,8 @@ static void virtio_net_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq) exit(1); } - iov = elem.out_sg; iov_cnt = elem.out_num; + iov2 = iov = g_memdup(elem.out_sg, sizeof(struct iovec) * elem.out_num); s = iov_to_buf(iov, iov_cnt, 0, &ctrl, sizeof(ctrl)); iov_discard_front(&iov, &iov_cnt, sizeof(ctrl)); if (s != sizeof(ctrl)) { @@ -833,6 +833,7 @@ static void virtio_net_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq) virtqueue_push(vq, &elem, sizeof(status)); virtio_notify(vdev, vq); + g_free(iov2); } }
virtio_net_handle_ctrl() and other functions that process control vq request call iov_discard_front() which will shorten the iov. This will lead unmapping in virtqueue_push() leaks mapping. Fixes this by keeping the original iov untouched and using a temp variable in those functions. Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Cc: qemu-stable@nongnu.org Signed-off-by: Jason Wang <jasowang@redhat.com> --- Changes from V1: - Use g_memdup() to simplify codes --- hw/net/virtio-net.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)