Messages in this thread Patch in this message | | | Subject | Re: [Intel-wired-lan] [PATCH net 2/2] ice: Fix NULL pointer deref during VF reset | From | Petr Oros <> | Date | Wed, 09 Aug 2023 20:14:03 +0200 |
| |
Przemek Kitszel píše v Čt 01. 01. 1970 v 00:00 +0000: > On 8/7/23 11:48, Petr Oros wrote: > > During stress test with attaching and detaching VF from KVM and > > simultaneously changing VFs spoofcheck and trust there was a > > NULL pointer dereference in ice_reset_vf that VF's VSI is null. > > > > More than one instance of ice_reset_vf() can be running at a given > > time. When we rebuild the VSI in ice_reset_vf, another reset can be > > triaged from ice_service_task. In this case we can access the > > currently > > uninitialized VSI and couse panic. The window for this racing > > condition > > has been around for a long time but it's much worse after commit > > 227bf4500aaa ("ice: move VSI delete outside deconfig") because > > the reset runs faster. ice_reset_vf() using vf->cfg_lock and when > > we move this lock before accessing to the VF VSI, we can fix > > BUG for all cases. > > > > Panic occurs sometimes in ice_vsi_is_rx_queue_active() and > > sometimes > > in ice_vsi_stop_all_rx_rings() > > > > With our reproducer, we can hint BUG: > > s/hint/hit/ > > > ~8h before commit 227bf4500aaa ("ice: move VSI delete outside > > deconfig"). > > ~20m after commit 227bf4500aaa ("ice: move VSI delete outside > > deconfig"). > > After this fix we are not able to reproduce it after ~48h > > > > There was commit cf90b74341ee ("ice: Fix call trace with null VSI > > during > > VF reset") which also tried to fix this issue, but it was only > > partially resolved and the bug still exists. > > > > [ 6420.658415] BUG: kernel NULL pointer dereference, address: > > 0000000000000000 > > [ 6420.665382] #PF: supervisor read access in kernel mode > > [ 6420.670521] #PF: error_code(0x0000) - not-present page > > [ 6420.675659] PGD 0 > > [ 6420.677679] Oops: 0000 [#1] PREEMPT SMP NOPTI > > [ 6420.682038] CPU: 53 PID: 326472 Comm: kworker/53:0 Kdump: loaded > > Not tainted 5.14.0-317.el9.x86_64 #1 > > [ 6420.691250] Hardware name: Dell Inc. PowerEdge R750/04V528, BIOS > > 1.6.5 04/15/2022 > > [ 6420.698729] Workqueue: ice ice_service_task [ice] > > [ 6420.703462] RIP: 0010:ice_vsi_is_rx_queue_active+0x2d/0x60 [ice] > > [ 6420.705860] ice 0000:ca:00.0: VF 0 is now untrusted > > [ 6420.709494] Code: 00 00 66 83 bf 76 04 00 00 00 48 8b 77 10 74 > > 3e 31 c0 eb 0f 0f b7 97 76 04 00 00 48 83 c0 01 39 c2 7e 2b 48 8b > > 97 68 04 00 00 <0f> b7 0c 42 48 8b 96 20 13 00 00 48 8d 94 8a 00 00 > > 12 00 8b 12 83 > > [ 6420.714426] ice 0000:ca:00.0 ens7f0: Setting MAC > > 22:22:22:22:22:00 on VF 0. VF driver will be reinitialized > > [ 6420.733120] RSP: 0018:ff778d2ff383fdd8 EFLAGS: 00010246 > > [ 6420.733123] RAX: 0000000000000000 RBX: ff2acf1916294000 RCX: > > 0000000000000000 > > [ 6420.733125] RDX: 0000000000000000 RSI: ff2acf1f2c6401a0 RDI: > > ff2acf1a27301828 > > [ 6420.762346] RBP: ff2acf1a27301828 R08: 0000000000000010 R09: > > 0000000000001000 > > [ 6420.769476] R10: ff2acf1916286000 R11: 00000000019eba3f R12: > > ff2acf19066460d0 > > [ 6420.776611] R13: ff2acf1f2c6401a0 R14: ff2acf1f2c6401a0 R15: > > 00000000ffffffff > > [ 6420.783742] FS: 0000000000000000(0000) > > GS:ff2acf28ffa80000(0000) knlGS:0000000000000000 > > [ 6420.791829] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > > [ 6420.797575] CR2: 0000000000000000 CR3: 00000016ad410003 CR4: > > 0000000000773ee0 > > [ 6420.804708] DR0: 0000000000000000 DR1: 0000000000000000 DR2: > > 0000000000000000 > > [ 6420.811034] vfio-pci 0000:ca:01.0: enabling device (0000 -> > > 0002) > > [ 6420.811840] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: > > 0000000000000400 > > [ 6420.811841] PKRU: 55555554 > > [ 6420.811842] Call Trace: > > [ 6420.811843] <TASK> > > [ 6420.811844] ice_reset_vf+0x9a/0x450 [ice] > > [ 6420.811876] ice_process_vflr_event+0x8f/0xc0 [ice] > > [ 6420.841343] ice_service_task+0x23b/0x600 [ice] > > [ 6420.845884] ? __schedule+0x212/0x550 > > [ 6420.849550] process_one_work+0x1e2/0x3b0 > > [ 6420.853563] ? rescuer_thread+0x390/0x390 > > [ 6420.857577] worker_thread+0x50/0x3a0 > > [ 6420.861242] ? rescuer_thread+0x390/0x390 > > [ 6420.865253] kthread+0xdd/0x100 > > [ 6420.868400] ? kthread_complete_and_exit+0x20/0x20 > > [ 6420.873194] ret_from_fork+0x1f/0x30 > > [ 6420.876774] </TASK> > > [ 6420.878967] Modules linked in: vfio_pci vfio_pci_core > > vfio_iommu_type1 vfio iavf vhost_net vhost vhost_iotlb tap tun > > xt_CHECKSUM xt_MASQUERADE xt_conntrack ipt_REJECT nf_reject_ipv4 > > nft_compat nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 > > nf_defrag_ipv4 nft_counter nf_tables bridge stp llc sctp > > ip6_udp_tunnel udp_tunnel nfp tls nfnetlink bluetooth mlx4_en > > mlx4_core rpcsec_gss_krb5 auth_rpcgss nfsv4 dns_resolver nfs lockd > > grace fscache netfs rfkill sunrpc intel_rapl_msr intel_rapl_common > > i10nm_edac nfit libnvdimm ipmi_ssif x86_pkg_temp_thermal > > intel_powerclamp coretemp irdma kvm_intel i40e kvm iTCO_wdt dcdbas > > ib_uverbs irqbypass iTCO_vendor_support mgag200 mei_me ib_core > > dell_smbios isst_if_mmio isst_if_mbox_pci rapl i2c_algo_bit > > drm_shmem_helper intel_cstate drm_kms_helper syscopyarea > > sysfillrect isst_if_common sysimgblt intel_uncore fb_sys_fops > > dell_wmi_descriptor wmi_bmof intel_vsec mei i2c_i801 acpi_ipmi > > ipmi_si i2c_smbus ipmi_devintf intel_pch_thermal acpi_power_meter > > pcspk > > r > > > > Fixes: efe41860008e ("ice: Fix memory corruption in VF driver") > > Fixes: f23df5220d2b ("ice: Fix spurious interrupt during removal of > > trusted VF") > > Signed-off-by: Petr Oros <poros@redhat.com> > > Thank you for all of your testing efforts, detailed explanation, > and the fix! > > Is there anything interesting about your setup/methodology? > (Asking rather to explore and extend our tests, no doubts here :)
This test is part of our QE test suite. There are a large number of "cfg stress" tests. I can't explain all the tests, but this one in particular just created 2 threads. One attaching/detaching VF from VM and the other sets VF parameters in a loop (trust, spoof check, mac addr) This causes concurrent access to resources during reset. ice/iavf are very sensitive to this type of stress ;)
We also using LNST, but it currently catches other types of bugs.
> > > --- > > drivers/net/ethernet/intel/ice/ice_vf_lib.c | 15 ++++++++------- > > 1 file changed, 8 insertions(+), 7 deletions(-) > > > > diff --git a/drivers/net/ethernet/intel/ice/ice_vf_lib.c > > b/drivers/net/ethernet/intel/ice/ice_vf_lib.c > > index 294e91c3453ccd..ea3310be8354cf 100644 > > --- a/drivers/net/ethernet/intel/ice/ice_vf_lib.c > > +++ b/drivers/net/ethernet/intel/ice/ice_vf_lib.c > > @@ -612,11 +612,17 @@ int ice_reset_vf(struct ice_vf *vf, u32 > > flags) > > return 0; > > } > > > > + if (flags & ICE_VF_RESET_LOCK) > > + mutex_lock(&vf->cfg_lock); > > + else > > + lockdep_assert_held(&vf->cfg_lock); > > + > > if (ice_is_vf_disabled(vf)) { > > vsi = ice_get_vf_vsi(vf); > > if (!vsi) { > > dev_dbg(dev, "VF is already removed\n"); > > - return -EINVAL; > > + err = -EINVAL; > > + goto out_unlock; > > } > > ice_vsi_stop_lan_tx_rings(vsi, ICE_NO_RESET, vf- > > >vf_id); > > > > @@ -625,14 +631,9 @@ int ice_reset_vf(struct ice_vf *vf, u32 flags) > > > > dev_dbg(dev, "VF is already disabled, there is no > > need for resetting it, telling VM, all is fine %d\n", > > vf->vf_id); > > - return 0; > > + goto out_unlock; > > } > > > > - if (flags & ICE_VF_RESET_LOCK) > > - mutex_lock(&vf->cfg_lock); > > - else > > - lockdep_assert_held(&vf->cfg_lock); > > - > > /* Set VF disable bit state here, before triggering reset > > */ > > set_bit(ICE_VF_STATE_DIS, vf->vf_states); > > ice_trigger_vf_reset(vf, flags & ICE_VF_RESET_VFLR, false); >
| |