>-----Original Message----- >From: Intel-wired-lan <[email protected]> On Behalf Of >Jiayuan Chen >Sent: Friday, June 26, 2026 10:39 AM >To: [email protected] >Cc: Jiayuan Chen <[email protected]>; Nguyen, Anthony L ><[email protected]>; Kitszel, Przemyslaw ><[email protected]>; Andrew Lunn <[email protected]>; David S. >Miller <[email protected]>; Eric Dumazet <[email protected]>; Jakub >Kicinski <[email protected]>; Paolo Abeni <[email protected]>; Jeff Garzik ><[email protected]>; Bruce Allan <[email protected]>; >[email protected]; [email protected] >Subject: [Intel-wired-lan] [PATCH net] e1000e: fix IRQ leak when request_irq() >fails in e1000_request_msix() > >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: ><TASK> >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 <[email protected]> >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; Thank you for the patch. I'd suggest to declare 'i' right in the loop, besides: Reviewed-by: Piotr Kwapulinski <[email protected]>
> > 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 > >
