On Tue, Jan 6, 2026 at 8:01 PM Breno Leitao leitao@debian.org wrote:

When bnxt_init_one() fails during initialization (e.g., bnxt_init_int_mode returns -ENODEV), the error path calls bnxt_free_hwrm_resources() which destroys the DMA pool and sets bp->hwrm_dma_pool to NULL. Subsequently, bnxt_ptp_clear() is called, which invokes ptp_clock_unregister().

Since commit a60fc3294a37 ("ptp: rework ptp_clock_unregister() to disable events"), ptp_clock_unregister() now calls ptp_disable_all_events(), which in turn invokes the driver's .enable() callback (bnxt_ptp_enable()) to disable PTP events before completing the unregistration.

bnxt_ptp_enable() attempts to send HWRM commands via bnxt_ptp_cfg_pin() and bnxt_ptp_cfg_event(), both of which call hwrm_req_init(). This function tries to allocate from bp->hwrm_dma_pool, causing a NULL pointer dereference:

bnxt_en 0000:01:00.0 (unnamed net_device) (uninitialized): bnxt_init_int_mode err: ffffffed KASAN: null-ptr-deref in range [0x0000000000000028-0x000000000000002f] Call Trace: __hwrm_req_init (drivers/net/ethernet/broadcom/bnxt/bnxt_hwrm.c:72) bnxt_ptp_enable (drivers/net/ethernet/broadcom/bnxt/bnxt_ptp.c:323 drivers/net/ethernet/broadcom/bnxt/bnxt_ptp.c:517) ptp_disable_all_events (drivers/ptp/ptp_chardev.c:66) ptp_clock_unregister (drivers/ptp/ptp_clock.c:518) bnxt_ptp_clear (drivers/net/ethernet/broadcom/bnxt/bnxt_ptp.c:1134) bnxt_init_one (drivers/net/ethernet/broadcom/bnxt/bnxt.c:16889)

Lines are against commit f8f9c1f4d0c7 ("Linux 6.19-rc3")

Fix this by clearing and unregistering ptp (bnxt_ptp_clear()) before freeing HWRM resources.

Suggested-by: Pavan Chebbi pavan.chebbi@broadcom.com Signed-off-by: Breno Leitao leitao@debian.org Fixes: a60fc3294a37 ("ptp: rework ptp_clock_unregister() to disable events") Cc: stable@vger.kernel.org

---

Changes in v3:

• Moved bp->ptp_cfg to be closer to the kfree(). (Pavan/Jakub)
• Link to v2: https://patch.msgid.link/20260105-bnxt-v2-1-9ac69edef726@debian.org

Changes in v2:

• Instead of checking for HWRM resources in bnxt_ptp_enable(), call it when HWRM resources are availble (Pavan Chebbi)
• Link to v1: https://patch.msgid.link/20251231-bnxt-v1-1-8f9cde6698b4@debian.org

---

drivers/net/ethernet/broadcom/bnxt/bnxt.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c index d160e54ac121..8419d1eb4035 100644 --- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c @@ -16891,12 +16891,12 @@ static int bnxt_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)

init_err_pci_clean: bnxt_hwrm_func_drv_unrgtr(bp);

•   bnxt_free_hwrm_resources(bp);
  

•   bnxt_hwmon_uninit(bp);
  

•   bnxt_ethtool_free(bp);
    bnxt_ptp_clear(bp);
    kfree(bp->ptp_cfg);
    bp->ptp_cfg = NULL;
  

•   bnxt_free_hwrm_resources(bp);
  

•   bnxt_hwmon_uninit(bp);
  

•   bnxt_ethtool_free(bp);
    kfree(bp->fw_health);
    bp->fw_health = NULL;
    bnxt_cleanup_pci(bp);
  
  

---

base-commit: e146b276a817807b8f4a94b5781bf80c6c00601b change-id: 20251231-bnxt-c54d317d8bfe

Best regards,

Breno Leitao leitao@debian.org

Thanks, Breno! Reviewed-by: Pavan Chebbi pavan.chebbi@broadcom.com