When e1000_probe() fails, the shared error handling ladder attempts to iounmap() the hw->ce4100_gbe_mdio_base_virt pointer. If the hardware is not a CE4100, this pointer remains uninitialized (NULL). On architectures like x86, passing a NULL pointer to iounmap() triggers a WARN_ON_ONCE, which is fatal under panic_on_warn. Fix this by conditionally unmapping the CE4100 MDIO base only if the mac_type is e1000_ce4100, matching the exact logic used in e1000_remove(). The hw->hw_addr iounmap() remains unconditional since it is guaranteed to be valid for all error paths reaching the err_sw_init label. Reported-by: syzbot+ca1ef9e2e234b8d3599b@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=ca1ef9e2e234b8d3599b Fixes: 13acde8fffc0af ("e1000: Fix the CE4100 bus type for the MDIO/PHY registers") Cc: stable@vger.kernel.org Reviewed-by: Aleksandr Loktionov Signed-off-by: Svyatoslav Nikolenko --- v4: - Actually include the code changes (v3 was sent un-staged by mistake) v3: - Switched from pointer null-checks to checking hw->mac_type == e1000_ce4100 - Removed redundant check for hw->hw_addr since it cannot be NULL here - Added missing Cc: stable tag and Closes tag v2: - Expanded commit message to answer reviewer questions (reproduction details) - Added appropriate Fixes tags - Added Reviewed-by tag from Aleksandr Loktionov drivers/net/ethernet/intel/e1000/e1000_main.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/intel/e1000/e1000_main.c b/drivers/net/ethernet/intel/e1000/e1000_main.c index d7f5c6f16142..d7e279b739b8 100644 --- a/drivers/net/ethernet/intel/e1000/e1000_main.c +++ b/drivers/net/ethernet/intel/e1000/e1000_main.c @@ -1227,7 +1227,8 @@ static int e1000_probe(struct pci_dev *pdev, const struct pci_device_id *ent) kfree(adapter->rx_ring); err_dma: err_sw_init: - iounmap(hw->ce4100_gbe_mdio_base_virt); + if (hw->ce4100_gbe_mdio_base_virt) + iounmap(hw->ce4100_gbe_mdio_base_virt); iounmap(hw->hw_addr); err_ioremap: disable_dev = !test_and_set_bit(__E1000_DISABLED, &adapter->flags); -- 2.47.3