> -----Original Message-----
> From: Svyatoslav Nikolenko <[email protected]>
> Sent: Monday, September 28, 2026 2:38 PM
> To: Nguyen, Anthony L <[email protected]>; Kitszel,
> Przemyslaw <[email protected]>; [email protected];
> [email protected]; [email protected]; [email protected];
> [email protected]
> Cc: [email protected]; [email protected]; linux-
> [email protected]; Svyatoslav Nikolenko
> <[email protected]>;
> [email protected];
> [email protected]
> Subject: [PATCH net v5] net: e1000: fix warning in iounmap on probe
> failure
>
> In e1000_probe(), the error unwinding path at err_sw_init
> unconditionally calls iounmap(hw->ce4100_gbe_mdio_base_virt). On non-
> CE4100 hardware,
> hw->ce4100_gbe_mdio_base_virt remains NULL.
> Passing NULL to iounmap() triggers a WARN_ON_ONCE on x86
> architectures.
> Furthermore, on CE4100 hardware, if probe fails before or during MDIO
> mapping, ce4100_gbe_mdio_base_virt is also NULL.
>
> Fix this by adding a NULL pointer check before calling iounmap() on
> hw->ce4100_gbe_mdio_base_virt. iounmap(hw->hw_addr) remains
> hw->unconditional
> because every code path reaching err_sw_init occurs after hw->hw_addr
> has been successfully mapped.
>
> Reported-by: [email protected]
> Closes: https://syzkaller.appspot.com/bug?extid=ca1ef9e2e234b8d3599b
> Fixes: 13acde8fffc0 ("e1000: cleanup CE4100 MDIO registers access")
> Cc: [email protected]
> Signed-off-by: Svyatoslav Nikolenko <[email protected]>
> ---
> v5:
> - Updated commit message and changelog to accurately describe the
> NULL pointer
> check implemented in the diff.
> - Fixed subject string in the Fixes: tag to match commit
> 13acde8fffc0.
> 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
>
> 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
Reviewed-by: Aleksandr Loktionov <[email protected]>
