From: Michal Schmidt <mschmidt@redhat.com> stable inclusion from stable-v6.6.136 commit d8a747057a17ffc79e31df1abb11d05e1669d8e5 category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/14640 CVE: CVE-2026-43094 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ Upstream commit 4821d563cd7f251ae728be1a6d04af82a294a5b9 ] Commit a7075f501bd3 ("ixgbevf: fix mailbox API compatibility by negotiating supported features") added the .negotiate_features callback to ixgbe_mac_operations and populated it in ixgbevf_mac_ops, but forgot to add it to ixgbevf_hv_mac_ops. This leaves the function pointer NULL on Hyper-V VMs. During probe, ixgbevf_negotiate_api() calls ixgbevf_set_features(), which unconditionally dereferences hw->mac.ops.negotiate_features(). On Hyper-V this results in a NULL pointer dereference: BUG: kernel NULL pointer dereference, address: 0000000000000000 [...] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine [...] Workqueue: events work_for_cpu_fn RIP: 0010:0x0 [...] Call Trace: ixgbevf_negotiate_api+0x66/0x160 [ixgbevf] ixgbevf_sw_init+0xe4/0x1f0 [ixgbevf] ixgbevf_probe+0x20f/0x4a0 [ixgbevf] local_pci_probe+0x50/0xa0 work_for_cpu_fn+0x1a/0x30 [...] Add ixgbevf_hv_negotiate_features_vf() that returns -EOPNOTSUPP and wire it into ixgbevf_hv_mac_ops. The caller already handles -EOPNOTSUPP gracefully. Fixes: a7075f501bd3 ("ixgbevf: fix mailbox API compatibility by negotiating supported features") Reported-by: Xiaoqiang Xiong <xxiong@redhat.com> Closes: https://issues.redhat.com/browse/RHEL-155455 Assisted-by: Claude:claude-4.6-opus-high Cursor Tested-by: Xiaoqiang Xiong <xxiong@redhat.com> Signed-off-by: Michal Schmidt <mschmidt@redhat.com> Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com> Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Pu Lehui <pulehui@huawei.com> --- drivers/net/ethernet/intel/ixgbevf/vf.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/net/ethernet/intel/ixgbevf/vf.c b/drivers/net/ethernet/intel/ixgbevf/vf.c index 65257107dfc8..92e5b0ec5c7d 100644 --- a/drivers/net/ethernet/intel/ixgbevf/vf.c +++ b/drivers/net/ethernet/intel/ixgbevf/vf.c @@ -709,6 +709,12 @@ static int ixgbevf_negotiate_features_vf(struct ixgbe_hw *hw, u32 *pf_features) return err; } +static int ixgbevf_hv_negotiate_features_vf(struct ixgbe_hw *hw, + u32 *pf_features) +{ + return -EOPNOTSUPP; +} + /** * ixgbevf_set_vfta_vf - Set/Unset VLAN filter table address * @hw: pointer to the HW structure @@ -1141,6 +1147,7 @@ static const struct ixgbe_mac_operations ixgbevf_hv_mac_ops = { .setup_link = ixgbevf_setup_mac_link_vf, .check_link = ixgbevf_hv_check_mac_link_vf, .negotiate_api_version = ixgbevf_hv_negotiate_api_version_vf, + .negotiate_features = ixgbevf_hv_negotiate_features_vf, .set_rar = ixgbevf_hv_set_rar_vf, .update_mc_addr_list = ixgbevf_hv_update_mc_addr_list_vf, .update_xcast_mode = ixgbevf_hv_update_xcast_mode, -- 2.34.1