The patch below does not apply to the 5.15-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 77d64d285be5f8d427893e9c54425b1e4f5d9be7 Mon Sep 17 00:00:00 2001 From: Ivan Vecera ivecera@redhat.com Date: Tue, 19 Apr 2022 16:22:21 +0200 Subject: [PATCH] ice: Protect vf_state check by cfg_lock in ice_vc_process_vf_msg()

Previous patch labelled "ice: Fix incorrect locking in ice_vc_process_vf_msg()" fixed an issue with ignored messages sent by VF driver but a small race window still left.

Recently caught trace during 'ip link set ... vf 0 vlan ...' operation:

[ 7332.995625] ice 0000:3b:00.0: Clearing port VLAN on VF 0 [ 7333.001023] iavf 0000:3b:01.0: Reset indication received from the PF [ 7333.007391] iavf 0000:3b:01.0: Scheduling reset task [ 7333.059575] iavf 0000:3b:01.0: PF returned error -5 (IAVF_ERR_PARAM) to our request 3 [ 7333.059626] ice 0000:3b:00.0: Invalid message from VF 0, opcode 3, len 4, error -1

Setting of VLAN for VF causes a reset of the affected VF using ice_reset_vf() function that runs with cfg_lock taken:

1. ice_notify_vf_reset() informs IAVF driver that reset is needed and IAVF schedules its own reset procedure 2. Bit ICE_VF_STATE_DIS is set in vf->vf_state 3. Misc initialization steps 4. ice_sriov_post_vsi_rebuild() -> ice_vf_set_initialized() and that clears ICE_VF_STATE_DIS in vf->vf_state

Step 3 is mentioned race window because IAVF reset procedure runs in parallel and one of its step is sending of VIRTCHNL_OP_GET_VF_RESOURCES message (opcode==3). This message is handled in ice_vc_process_vf_msg() and if it is received during the mentioned race window then it's marked as invalid and error is returned to VF driver.

Protect vf_state check in ice_vc_process_vf_msg() by cfg_lock to avoid this race condition.

Fixes: e6ba5273d4ed ("ice: Fix race conditions between virtchnl handling and VF ndo ops") Tested-by: Fei Liu feliu@redhat.com Signed-off-by: Ivan Vecera ivecera@redhat.com Reviewed-by: Jacob Keller jacob.e.keller@intel.com Tested-by: Konrad Jankowski konrad0.jankowski@intel.com Signed-off-by: Tony Nguyen anthony.l.nguyen@intel.com

diff --git a/drivers/net/ethernet/intel/ice/ice_virtchnl.c b/drivers/net/ethernet/intel/ice/ice_virtchnl.c index 5612c032f15a..b72606c9e6d0 100644 --- a/drivers/net/ethernet/intel/ice/ice_virtchnl.c +++ b/drivers/net/ethernet/intel/ice/ice_virtchnl.c @@ -3625,6 +3625,8 @@ void ice_vc_process_vf_msg(struct ice_pf *pf, struct ice_rq_event_info *event) return; }

+ mutex_lock(&vf->cfg_lock); + /* Check if VF is disabled. */ if (test_bit(ICE_VF_STATE_DIS, vf->vf_states)) { err = -EPERM; @@ -3648,19 +3650,14 @@ void ice_vc_process_vf_msg(struct ice_pf *pf, struct ice_rq_event_info *event) NULL, 0); dev_err(dev, "Invalid message from VF %d, opcode %d, len %d, error %d\n", vf_id, v_opcode, msglen, err); - ice_put_vf(vf); - return; + goto finish; }

- mutex_lock(&vf->cfg_lock); - if (!ice_vc_is_opcode_allowed(vf, v_opcode)) { ice_vc_send_msg_to_vf(vf, v_opcode, VIRTCHNL_STATUS_ERR_NOT_SUPPORTED, NULL, 0); - mutex_unlock(&vf->cfg_lock); - ice_put_vf(vf); - return; + goto finish; }

switch (v_opcode) { @@ -3773,6 +3770,7 @@ void ice_vc_process_vf_msg(struct ice_pf *pf, struct ice_rq_event_info *event) vf_id, v_opcode, err); }

+finish: mutex_unlock(&vf->cfg_lock); ice_put_vf(vf); }