An internal syzbot instance reported the warning below. comedi (comedi_parport) lets userspace request_irq() an arbitrary IRQ number and can thus grab one of e1000e's MSI-X vectors. When e1000_request_msix() then fails partway through, it returned without freeing the vectors it had already requested; pci_disable_msix() later tears those descriptors down while their irqaction is still attached, leaking the /proc/irq entry. Free the already requested IRQs on the error path. genirq: Flags mismatch irq 28. 00200000 (eth1-tx-0) vs. 00200000 (comedi_parport) remove_proc_entry: removing non-empty directory 'irq/27', leaking at least 'eth1-rx-0' WARNING: fs/proc/generic.c:742 at remove_proc_entry+0x436/0x560, CPU#3: ip/445 Modules linked in: CPU: 3 UID: 0 PID: 445 Comm: ip Not tainted 7.1.0+ #284 PREEMPT RIP: 0010:remove_proc_entry (fs/proc/generic.c:742 (discriminator 4)) PKRU: 55555554 Call Trace: unregister_irq_proc (kernel/irq/proc.c:406) free_desc (kernel/irq/irqdesc.c:482) irq_free_descs (kernel/irq/irqdesc.c:874 kernel/irq/irqdesc.c:865) irq_domain_free_irqs (kernel/irq/irqdomain.c:1917) msi_domain_free_locked.part.0 (kernel/irq/msi.c:1619 kernel/irq/msi.c:1645) msi_domain_free_irqs_all_locked (kernel/irq/msi.c:1632) pci_msi_teardown_msi_irqs (drivers/pci/msi/irqdomain.c:28) pci_free_msi_irqs (drivers/pci/msi/msi.c:925) pci_disable_msix (drivers/pci/msi/api.c:200 drivers/pci/msi/api.c:193) e1000_request_irq (drivers/net/ethernet/intel/e1000e/netdev.c:2028) e1000e_open (drivers/net/ethernet/intel/e1000e/netdev.c:4681) __dev_open (net/core/dev.c:1702) netif_change_flags (net/core/dev.c:9806) do_setlink.isra.0 (net/core/rtnetlink.c:3207 (discriminator 1)) rtnetlink_rcv_msg (net/core/rtnetlink.c:7068) netlink_rcv_skb (net/netlink/af_netlink.c:2556) Fixes: 4662e82b2cb4 ("e1000e: add support for new 82574L part") Signed-off-by: Jiayuan Chen Assisted-by: Claude:claude-opus-4-8 --- drivers/net/ethernet/intel/e1000e/netdev.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c b/drivers/net/ethernet/intel/e1000e/netdev.c index 808e5cddd6a9..19b9823c5679 100644 --- a/drivers/net/ethernet/intel/e1000e/netdev.c +++ b/drivers/net/ethernet/intel/e1000e/netdev.c @@ -2099,7 +2099,7 @@ void e1000e_set_interrupt_capability(struct e1000_adapter *adapter) static int e1000_request_msix(struct e1000_adapter *adapter) { struct net_device *netdev = adapter->netdev; - int err = 0, vector = 0; + int err = 0, vector = 0, i; if (strlen(netdev->name) < (IFNAMSIZ - 5)) snprintf(adapter->rx_ring->name, @@ -2111,7 +2111,7 @@ static int e1000_request_msix(struct e1000_adapter *adapter) e1000_intr_msix_rx, 0, adapter->rx_ring->name, netdev); if (err) - return err; + goto err_free; adapter->rx_ring->itr_register = adapter->hw.hw_addr + E1000_EITR_82574(vector); adapter->rx_ring->itr_val = adapter->itr; @@ -2127,7 +2127,7 @@ static int e1000_request_msix(struct e1000_adapter *adapter) e1000_intr_msix_tx, 0, adapter->tx_ring->name, netdev); if (err) - return err; + goto err_free; adapter->tx_ring->itr_register = adapter->hw.hw_addr + E1000_EITR_82574(vector); adapter->tx_ring->itr_val = adapter->itr; @@ -2136,11 +2136,16 @@ static int e1000_request_msix(struct e1000_adapter *adapter) err = request_irq(adapter->msix_entries[vector].vector, e1000_msix_other, 0, netdev->name, netdev); if (err) - return err; + goto err_free; e1000_configure_msix(adapter); return 0; + +err_free: + for (i = vector - 1; i >= 0; i--) + free_irq(adapter->msix_entries[i].vector, netdev); + return err; } /** -- 2.43.0