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| author |   Saurabh Sengar <ssengar@linux.microsoft.com> | 2025-05-29 03:18:30 -0700 |
|---|---|---|
| committer |   Jakub Kicinski <kuba@kernel.org> | 2025-05-30 19:31:25 -0700 |
| commit | 3ec523304976648b45a3eef045e97d17122ff1b2 (patch) | |
| tree | 6817b670518ebbfc8f0b90d14e70b4cef63952a4 | |
| parent | net: Fix net_devmem_bind_dmabuf for non-devmem configs (diff) | |
| download | wireguard-linux-3ec523304976648b45a3eef045e97d17122ff1b2.tar.xz wireguard-linux-3ec523304976648b45a3eef045e97d17122ff1b2.zip | |
hv_netvsc: fix potential deadlock in netvsc_vf_setxdp()
The MANA driver's probe registers netdevice via the following call chain:
mana_probe()
register_netdev()
register_netdevice()
register_netdevice() calls notifier callback for netvsc driver,
holding the netdev mutex via netdev_lock_ops().
Further this netvsc notifier callback end up attempting to acquire the
same lock again in dev_xdp_propagate() leading to deadlock.
netvsc_netdev_event()
netvsc_vf_setxdp()
dev_xdp_propagate()
This deadlock was not observed so far because net_shaper_ops was never set,
and thus the lock was effectively a no-op in this case. Fix this by using
netif_xdp_propagate() instead of dev_xdp_propagate() to avoid recursive
locking in this path.
And, since no deadlock is observed on the other path which is via
netvsc_probe, add the lock exclusivly for that path.
Also, clean up the unregistration path by removing the unnecessary call to
netvsc_vf_setxdp(), since unregister_netdevice_many_notify() already
performs this cleanup via dev_xdp_uninstall().
Fixes: 97246d6d21c2 ("net: hold netdev instance lock during ndo_bpf")
Cc: stable@vger.kernel.org
Signed-off-by: Saurabh Sengar <ssengar@linux.microsoft.com>
Tested-by: Erni Sri Satya Vennela <ernis@linux.microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Reviewed-by: Subbaraya Sundeep <sbhatta@marvell.com>
Link: https://patch.msgid.link/1748513910-23963-1-git-send-email-ssengar@linux.microsoft.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
| -rw-r--r-- | drivers/net/hyperv/netvsc_bpf.c | 2 | ||||
| -rw-r--r-- | drivers/net/hyperv/netvsc_drv.c | 4 | ||||
| -rw-r--r-- | net/core/dev.c | 1 |
3 files changed, 4 insertions, 3 deletions
diff --git a/drivers/net/hyperv/netvsc_bpf.c b/drivers/net/hyperv/netvsc_bpf.c index e01c5997a551..1dd3755d9e6d 100644 --- a/drivers/net/hyperv/netvsc_bpf.c +++ b/drivers/net/hyperv/netvsc_bpf.c @@ -183,7 +183,7 @@ int netvsc_vf_setxdp(struct net_device *vf_netdev, struct bpf_prog *prog) xdp.command = XDP_SETUP_PROG; xdp.prog = prog; - ret = dev_xdp_propagate(vf_netdev, &xdp); + ret = netif_xdp_propagate(vf_netdev, &xdp); if (ret && prog) bpf_prog_put(prog); diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c index 14a0d04e21ae..c41a025c66f0 100644 --- a/drivers/net/hyperv/netvsc_drv.c +++ b/drivers/net/hyperv/netvsc_drv.c @@ -2462,8 +2462,6 @@ static int netvsc_unregister_vf(struct net_device *vf_netdev) netdev_info(ndev, "VF unregistering: %s\n", vf_netdev->name); - netvsc_vf_setxdp(vf_netdev, NULL); - reinit_completion(&net_device_ctx->vf_add); netdev_rx_handler_unregister(vf_netdev); netdev_upper_dev_unlink(vf_netdev, ndev); @@ -2631,7 +2629,9 @@ static int netvsc_probe(struct hv_device *dev, continue; netvsc_prepare_bonding(vf_netdev); + netdev_lock_ops(vf_netdev); netvsc_register_vf(vf_netdev, VF_REG_IN_PROBE); + netdev_unlock_ops(vf_netdev); __netvsc_vf_setup(net, vf_netdev); break; } diff --git a/net/core/dev.c b/net/core/dev.c index 2b514d95c528..a388f459a366 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -9968,6 +9968,7 @@ int netif_xdp_propagate(struct net_device *dev, struct netdev_bpf *bpf) return dev->netdev_ops->ndo_bpf(dev, bpf); } +EXPORT_SYMBOL_GPL(netif_xdp_propagate); u32 dev_xdp_prog_id(struct net_device *dev, enum bpf_xdp_mode mode) { |