From: Xuanqiang Luo The time sync interrupt queues ptp_extts0_work, which reads device registers and reports events through pf->ptp_clock. i40e_ptp_stop() unregisters the PHC without first disabling the event source or draining the work. The worker can therefore access the clock or PF after either has been freed, causing a use-after-free. Disable external timestamp events and call disable_work_sync() before unregistering the PHC. Disabling the work also prevents an interrupt already in progress from queuing it after the drain. INIT_WORK() is called from i40e_ptp_set_timestamp_mode(), which runs on reset and whenever timestamping is reconfigured. Reinitializing pending or running work can corrupt its workqueue state. Initialize the work once from i40e_sw_init() instead. Also exclude reset recovery before stopping PTP so a concurrent rebuild cannot re-enable timestamp events or recreate the PHC during removal. Fixes: 1050713026a0 ("i40e: add support for PTP external synchronization clock") Signed-off-by: Xuanqiang Luo --- drivers/net/ethernet/intel/i40e/i40e.h | 1 + drivers/net/ethernet/intel/i40e/i40e_main.c | 17 +++++++------- drivers/net/ethernet/intel/i40e/i40e_ptp.c | 25 +++++++++++++++------ 3 files changed, 28 insertions(+), 15 deletions(-) diff --git a/drivers/net/ethernet/intel/i40e/i40e.h b/drivers/net/ethernet/intel/i40e/i40e.h index 83e780919ac97..e2ae61bc38786 100644 --- a/drivers/net/ethernet/intel/i40e/i40e.h +++ b/drivers/net/ethernet/intel/i40e/i40e.h @@ -1315,6 +1315,7 @@ int i40e_ptp_hwtstamp_set(struct net_device *netdev, struct netlink_ext_ack *extack); void i40e_ptp_save_hw_time(struct i40e_pf *pf); void i40e_ptp_restore_hw_time(struct i40e_pf *pf); +void i40e_ptp_init_work(struct i40e_pf *pf); void i40e_ptp_init(struct i40e_pf *pf); void i40e_ptp_stop(struct i40e_pf *pf); int i40e_ptp_alloc_pins(struct i40e_pf *pf); diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c index a04683004a567..2909a58d57562 100644 --- a/drivers/net/ethernet/intel/i40e/i40e_main.c +++ b/drivers/net/ethernet/intel/i40e/i40e_main.c @@ -12819,6 +12819,7 @@ static int i40e_sw_init(struct i40e_pf *pf) "total-port-shutdown was enabled, link-down-on-close is forced on\n"); } mutex_init(&pf->switch_mutex); + i40e_ptp_init_work(pf); sw_init_done: return err; @@ -16157,14 +16158,6 @@ static void i40e_remove(struct pci_dev *pdev) i40e_devlink_unregister(pf); - i40e_dbg_pf_exit(pf); - - i40e_ptp_stop(pf); - - /* Disable RSS in hw */ - i40e_write_rx_ctl(hw, I40E_PFQF_HENA(0), 0); - i40e_write_rx_ctl(hw, I40E_PFQF_HENA(1), 0); - /* Grab __I40E_RESET_RECOVERY_PENDING and set __I40E_IN_REMOVE * flags, once they are set, i40e_rebuild should not be called as * i40e_prep_for_reset always returns early. @@ -16173,6 +16166,14 @@ static void i40e_remove(struct pci_dev *pdev) usleep_range(1000, 2000); set_bit(__I40E_IN_REMOVE, pf->state); + i40e_dbg_pf_exit(pf); + + i40e_ptp_stop(pf); + + /* Disable RSS in hw */ + i40e_write_rx_ctl(hw, I40E_PFQF_HENA(0), 0); + i40e_write_rx_ctl(hw, I40E_PFQF_HENA(1), 0); + if (test_bit(I40E_FLAG_SRIOV_ENA, pf->flags)) { set_bit(__I40E_VF_RESETS_DISABLED, pf->state); i40e_free_vfs(pf); diff --git a/drivers/net/ethernet/intel/i40e/i40e_ptp.c b/drivers/net/ethernet/intel/i40e/i40e_ptp.c index ff62b5f2c8150..fd51ab8c10c20 100644 --- a/drivers/net/ethernet/intel/i40e/i40e_ptp.c +++ b/drivers/net/ethernet/intel/i40e/i40e_ptp.c @@ -169,6 +169,17 @@ static void i40e_ptp_extts0_work(struct work_struct *work) ptp_clock_event(pf->ptp_clock, &event); } +/** + * i40e_ptp_init_work - Initialize PTP work for a PF + * @pf: Board private structure + * + * Initialize work which must remain valid for the lifetime of the PF. + */ +void i40e_ptp_init_work(struct i40e_pf *pf) +{ + INIT_WORK(&pf->ptp_extts0_work, i40e_ptp_extts0_work); +} + /** * i40e_is_ptp_pin_dev - check if device supports PTP pins * @hw: pointer to the hardware structure @@ -1186,8 +1197,6 @@ static int i40e_ptp_set_timestamp_mode(struct i40e_pf *pf, regval |= 1 << I40E_PRTTSYN_CTL0_EVENT_INT_ENA_SHIFT; wr32(hw, I40E_PRTTSYN_CTL0, regval); - INIT_WORK(&pf->ptp_extts0_work, i40e_ptp_extts0_work); - switch (config->tx_type) { case HWTSTAMP_TX_OFF: pf->ptp_tx = false; @@ -1541,6 +1550,13 @@ void i40e_ptp_stop(struct i40e_pf *pf) struct i40e_hw *hw = &pf->hw; u32 regval; + /* Stop external timestamp events before unregistering the clock. */ + regval = rd32(hw, I40E_PRTTSYN_CTL0); + regval &= ~I40E_PRTTSYN_CTL0_EVENT_INT_ENA_MASK; + wr32(hw, I40E_PRTTSYN_CTL0, regval); + + disable_work_sync(&pf->ptp_extts0_work); + clear_bit(I40E_FLAG_PTP_ENA, pf->flags); pf->ptp_tx = false; pf->ptp_rx = false; @@ -1570,10 +1586,5 @@ void i40e_ptp_stop(struct i40e_pf *pf) regval &= ~I40E_PRTTSYN_AUX_0_PTPFLAG_MASK; wr32(hw, I40E_PRTTSYN_AUX_0(0), regval); - /* Disable interrupts */ - regval = rd32(hw, I40E_PRTTSYN_CTL0); - regval &= ~I40E_PRTTSYN_CTL0_EVENT_INT_ENA_MASK; - wr32(hw, I40E_PRTTSYN_CTL0, regval); - i40e_ptp_free_pins(pf); } -- 2.43.0