In the Linux kernel, the following vulnerability has been resolved:
netfilter: br_netfilter: skip conntrack input hook for promisc packets
For historical reasons, when bridge device is in promisc mode, packets that are directed to the taps follow bridge input hook path. This patch adds a workaround to reset conntrack for these packets.
Jianbo Liu reports warning splats in their test infrastructure where cloned packets reach the br_netfilter input hook to confirm the conntrack object.
Scratch one bit from BR_INPUT_SKB_CB to annotate that this packet has reached the input hook because it is passed up to the bridge device to reach the taps.
[ 57.571874] WARNING: CPU: 1 PID: 0 at net/bridge/br_netfilter_hooks.c:616 br_nf_local_in+0x157/0x180 [br_netfilter] [ 57.572749] Modules linked in: xt_MASQUERADE nf_conntrack_netlink nfnetlink iptable_nat xt_addrtype xt_conntrack nf_nat br_netfilter rpcsec_gss_krb5 auth_rpcgss oid_registry overlay rpcrdma rdma_ucm ib_iser libiscsi scsi_transport_isc si ib_umad rdma_cm ib_ipoib iw_cm ib_cm mlx5_ib ib_uverbs ib_core mlx5ctl mlx5_core [ 57.575158] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 6.8.0+ #19 [ 57.575700] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014 [ 57.576662] RIP: 0010:br_nf_local_in+0x157/0x180 [br_netfilter] [ 57.577195] Code: fe ff ff 41 bd 04 00 00 00 be 04 00 00 00 e9 4a ff ff ff be 04 00 00 00 48 89 ef e8 f3 a9 3c e1 66 83 ad b4 00 00 00 04 eb 91 <0f> 0b e9 f1 fe ff ff 0f 0b e9 df fe ff ff 48 89 df e8 b3 53 47 e1 [ 57.578722] RSP: 0018:ffff88885f845a08 EFLAGS: 00010202 [ 57.579207] RAX: 0000000000000002 RBX: ffff88812dfe8000 RCX: 0000000000000000 [ 57.579830] RDX: ffff88885f845a60 RSI: ffff8881022dc300 RDI: 0000000000000000 [ 57.580454] RBP: ffff88885f845a60 R08: 0000000000000001 R09: 0000000000000003 [ 57.581076] R10: 00000000ffff1300 R11: 0000000000000002 R12: 0000000000000000 [ 57.581695] R13: ffff8881047ffe00 R14: ffff888108dbee00 R15: ffff88814519b800 [ 57.582313] FS: 0000000000000000(0000) GS:ffff88885f840000(0000) knlGS:0000000000000000 [ 57.583040] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 57.583564] CR2: 000000c4206aa000 CR3: 0000000103847001 CR4: 0000000000370eb0 [ 57.584194] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 57.584820] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 57.585440] Call Trace: [ 57.585721] <IRQ> [ 57.585976] ? __warn+0x7d/0x130 [ 57.586323] ? br_nf_local_in+0x157/0x180 [br_netfilter] [ 57.586811] ? report_bug+0xf1/0x1c0 [ 57.587177] ? handle_bug+0x3f/0x70 [ 57.587539] ? exc_invalid_op+0x13/0x60 [ 57.587929] ? asm_exc_invalid_op+0x16/0x20 [ 57.588336] ? br_nf_local_in+0x157/0x180 [br_netfilter] [ 57.588825] nf_hook_slow+0x3d/0xd0 [ 57.589188] ? br_handle_vlan+0x4b/0x110 [ 57.589579] br_pass_frame_up+0xfc/0x150 [ 57.589970] ? br_port_flags_change+0x40/0x40 [ 57.590396] br_handle_frame_finish+0x346/0x5e0 [ 57.590837] ? ipt_do_table+0x32e/0x430 [ 57.591221] ? br_handle_local_finish+0x20/0x20 [ 57.591656] br_nf_hook_thresh+0x4b/0xf0 [br_netfilter] [ 57.592286] ? br_handle_local_finish+0x20/0x20 [ 57.592802] br_nf_pre_routing_finish+0x178/0x480 [br_netfilter] [ 57.593348] ? br_handle_local_finish+0x20/0x20 [ 57.593782] ? nf_nat_ipv4_pre_routing+0x25/0x60 [nf_nat] [ 57.594279] br_nf_pre_routing+0x24c/0x550 [br_netfilter] [ 57.594780] ? br_nf_hook_thresh+0xf0/0xf0 [br_netfilter] [ 57.595280] br_handle_frame+0x1f3/0x3d0 [ 57.595676] ? br_handle_local_finish+0x20/0x20 [ 57.596118] ? br_handle_frame_finish+0x5e0/0x5e0 [ 57.596566] __netif_receive_skb_core+0x25b/0xfc0 [ 57.597017] ? __napi_build_skb+0x37/0x40 [ 57.597418] __netif_receive_skb_list_core+0xfb/0x220
CVSS Details
- CVSS 3.1 Base Score: 8.2
- CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H)
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Amazon Linux Ami 2 | — | Upgrade kernel-headersUpgrade kernel-tools-develUpgrade kernel-develUpgrade python-perf-debuginfoUpgrade kernel-debuginfoUpgrade kernel-livepatch-5.15.158-103.164Upgrade kernelUpgrade kernel-tools-debuginfoUpgrade kernel-debuginfo-common-x86_64Upgrade perfUpgrade kernel-toolsUpgrade bpftoolUpgrade perf-debuginfoUpgrade python-perfUpgrade kernel-debuginfo-common-aarch64Upgrade bpftool-debuginfo | Aug 14, 2024 | May 1, 2024 |
| Amazon_linux_2023 | — | Upgrade kernel-tools-debuginfoUpgrade kernel-develUpgrade kernel-libbpf-staticUpgrade python3-perfUpgrade kernel-debuginfo-common-aarch64Upgrade perfUpgrade kernel-modules-extraUpgrade kernel-toolsUpgrade kernel-modules-extra-commonUpgrade bpftoolUpgrade kernel-livepatch-6.1.90-99.173Upgrade python3-perf-debuginfoUpgrade kernel-tools-develUpgrade bpftool-debuginfoUpgrade kernel-libbpf-develUpgrade kernel-debuginfo-common-x86_64Upgrade kernelUpgrade kernel-debuginfoUpgrade perf-debuginfoUpgrade kernel-headersUpgrade kernel-libbpf | Feb 17, 2025 | May 1, 2024 |
| Debian | — | Upgrade linux | May 8, 2024 | May 1, 2024 |
| Redhat_linux | — | No solution exists | Jul 9, 2025 | May 1, 2024 |
| Suse | — | Upgrade kernel-develUpgrade gfs2-kmp-64kbUpgrade kernel-default-livepatchUpgrade kernel-zfcpdumpUpgrade gfs2-kmp-azureUpgrade kernel-default-optionalUpgrade kernel-obs-buildUpgrade kernel-default-vdsoUpgrade kernel-rt-develUpgrade kernel-sourceUpgrade kernel-rt_debug-develUpgrade kernel-devel-azureUpgrade ocfs2-kmp-rtUpgrade kselftests-kmp-azureUpgrade dtb-freescaleUpgrade cluster-md-kmp-azureUpgrade dtb-exynosUpgrade kernel-rtUpgrade kernel-kvmsmallUpgrade reiserfs-kmp-azureUpgrade kernel-source-azureUpgrade dtb-lgUpgrade kernel-azure-develUpgrade dtb-allwinnerUpgrade kernel-64kb-develUpgrade dtb-amdUpgrade dtb-nvidiaUpgrade reiserfs-kmp-defaultUpgrade kernel-kvmsmall-vdsoUpgrade gfs2-kmp-defaultUpgrade kernel-debug-vdsoUpgrade dtb-armUpgrade kernel-debugUpgrade kernel-rt_debug-vdsoUpgrade reiserfs-kmp-rtUpgrade kernel-macrosUpgrade kernel-64kb-optionalUpgrade dlm-kmp-defaultUpgrade dtb-appleUpgrade cluster-md-kmp-defaultUpgrade kernel-docs-htmlUpgrade kernel-docsUpgrade kernel-debug-develUpgrade kernel-azure-vdsoUpgrade kernel-azure-extraUpgrade kernel-64kb-extraUpgrade dtb-broadcomUpgrade dlm-kmp-azureUpgrade cluster-md-kmp-64kbUpgrade kselftests-kmp-defaultUpgrade kernel-rt-vdsoUpgrade kernel-rt-optionalUpgrade kernel-default-livepatch-develUpgrade dtb-hisiliconUpgrade ocfs2-kmp-64kbUpgrade kernel-default-extraUpgrade kernel-default-baseUpgrade dtb-sprdUpgrade dtb-renesasUpgrade kernel-syms-rtUpgrade kernel-source-rtUpgrade kernel-rt_debugUpgrade kernel-symsUpgrade kernel-obs-qaUpgrade dlm-kmp-rtUpgrade ocfs2-kmp-azureUpgrade kernel-defaultUpgrade dtb-apmUpgrade dtb-socionextUpgrade reiserfs-kmp-64kbUpgrade kselftests-kmp-rtUpgrade kernel-rt-livepatch-develUpgrade dtb-marvellUpgrade kernel-rt-extraUpgrade dtb-amlogicUpgrade kernel-syms-azureUpgrade kernel-default-base-rebuildUpgrade kernel-devel-rtUpgrade kernel-source-vanillaUpgrade dtb-caviumUpgrade dtb-mediatekUpgrade dtb-amazonUpgrade kernel-64kbUpgrade gfs2-kmp-rtUpgrade dlm-kmp-64kbUpgrade kernel-azure-optionalUpgrade dtb-xilinxUpgrade dtb-alteraUpgrade dtb-rockchipUpgrade kselftests-kmp-64kbUpgrade ocfs2-kmp-defaultUpgrade cluster-md-kmp-rtUpgrade kernel-default-develUpgrade dtb-qcomUpgrade kernel-azureUpgrade kernel-kvmsmall-devel | Dec 5, 2025 | May 21, 2025 |
| Ubuntu | — | Upgrade linux-image-generic-lpaeUpgrade linux-image-5.15.0-1068-azureUpgrade linux-image-oem-24.04Upgrade linux-image-gke-5.15Upgrade linux-image-generic-64kUpgrade linux-image-6.8.0-38-generic-64kUpgrade linux-image-6.8.0-1006-gkeUpgrade linux-image-generic-64k-hwe-20.04Upgrade linux-image-6.8.0-1009-nvidia-64kUpgrade linux-image-lowlatency-64kUpgrade linux-image-intel-iotgUpgrade linux-image-lowlatency-64k-hwe-20.04Upgrade linux-image-6.8.0-1011-awsUpgrade linux-image-genericUpgrade linux-image-gkeopUpgrade linux-image-5.15.0-116-generic-lpaeUpgrade linux-image-gcp-lts-22.04Upgrade linux-image-5.15.0-1065-gcpUpgrade linux-image-5.15.0-1063-oracleUpgrade linux-image-gkeUpgrade linux-image-6.8.0-38-lowlatency-64kUpgrade linux-image-nvidia-lowlatencyUpgrade linux-image-5.15.0-116-lowlatency-64kUpgrade linux-image-6.8.0-1010-azureUpgrade linux-image-oem-20.04Upgrade linux-image-6.8.0-1010-gcpUpgrade linux-image-6.8.0-38-lowlatencyUpgrade linux-image-azure-lts-22.04Upgrade linux-image-oracle-lts-22.04Upgrade linux-image-lowlatencyUpgrade linux-image-oem-20.04bUpgrade linux-image-ibmUpgrade linux-image-xilinx-zynqmpUpgrade linux-image-5.15.0-1060-intel-iotgUpgrade linux-image-nvidiaUpgrade linux-image-6.8.0-1008-oracle-64kUpgrade linux-image-intelUpgrade linux-image-6.8.0-1010-azure-fdeUpgrade linux-image-5.15.0-1062-kvmUpgrade linux-image-6.8.0-1009-nvidiaUpgrade linux-image-5.15.0-1062-gkeUpgrade linux-image-azure-cvmUpgrade linux-image-aws-lts-22.04Upgrade linux-image-kvmUpgrade linux-image-5.15.0-116-genericUpgrade linux-image-azureUpgrade linux-image-generic-lpae-hwe-20.04Upgrade linux-image-generic-hwe-20.04Upgrade linux-image-6.8.0-38-genericUpgrade linux-image-6.8.0-1008-ibmUpgrade linux-image-raspiUpgrade linux-image-gcpUpgrade linux-image-gkeop-5.15Upgrade linux-image-5.15.0-1060-nvidia-lowlatencyUpgrade linux-image-lowlatency-hwe-20.04Upgrade linux-image-5.15.0-1035-xilinx-zynqmpUpgrade linux-image-virtual-hwe-20.04Upgrade linux-image-6.8.0-1008-oracleUpgrade linux-image-6.8.0-1008-oemUpgrade linux-image-oem-20.04cUpgrade linux-image-6.8.0-1007-intelUpgrade linux-image-virtual-hwe-24.04Upgrade linux-image-oracle-64kUpgrade linux-image-nvidia-64kUpgrade linux-image-azure-fde-lts-22.04Upgrade linux-image-generic-hwe-24.04Upgrade linux-image-oem-20.04dUpgrade linux-image-5.15.0-116-generic-64kUpgrade linux-image-5.15.0-1048-gkeopUpgrade linux-image-azure-fdeUpgrade linux-image-5.15.0-1065-awsUpgrade linux-image-6.8.0-1007-raspiUpgrade linux-image-ibm-classicUpgrade linux-image-5.15.0-1058-ibmUpgrade linux-image-5.15.0-1068-azure-fdeUpgrade linux-image-oracleUpgrade linux-image-5.15.0-1064-gcpUpgrade linux-image-awsUpgrade linux-image-virtualUpgrade linux-image-ibm-lts-24.04Upgrade linux-image-generic-64k-hwe-24.04Upgrade linux-image-oem-24.04aUpgrade linux-image-5.15.0-1060-nvidiaUpgrade linux-image-5.15.0-116-lowlatency | Jul 12, 2024 | May 1, 2024 |
| Vmware Photon_os | — | Use 'tdnf update' to upgrade all packages to the latest version. | Jan 20, 2025 | May 1, 2024 |
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