{"id":"CVE-2026-43466","summary":"net/mlx5e: Fix DMA FIFO desync on error CQE SQ recovery","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/mlx5e: Fix DMA FIFO desync on error CQE SQ recovery\n\nIn case of a TX error CQE, a recovery flow is triggered,\nmlx5e_reset_txqsq_cc_pc() resets dma_fifo_cc to 0 but not dma_fifo_pc,\ndesyncing the DMA FIFO producer and consumer.\n\nAfter recovery, the producer pushes new DMA entries at the old\ndma_fifo_pc, while the consumer reads from position 0.\nThis causes us to unmap stale DMA addresses from before the recovery.\n\nThe DMA FIFO is a purely software construct with no HW counterpart.\nAt the point of reset, all WQEs have been flushed so dma_fifo_cc is\nalready equal to dma_fifo_pc. There is no need to reset either counter,\nsimilar to how skb_fifo pc/cc are untouched.\n\nRemove the 'dma_fifo_cc = 0' reset.\n\nThis fixes the following WARNING:\n    WARNING: CPU: 0 PID: 0 at drivers/iommu/dma-iommu.c:1240 iommu_dma_unmap_page+0x79/0x90\n    Modules linked in: mlx5_vdpa vringh vdpa bonding mlx5_ib mlx5_vfio_pci ipip mlx5_fwctl tunnel4 mlx5_core ib_ipoib geneve ip6_gre ip_gre gre nf_tables ip6_tunnel rdma_ucm ib_uverbs ib_umad vfio_pci vfio_pci_core act_mirred act_skbedit act_vlan vhost_net vhost tap ip6table_mangle ip6table_nat ip6table_filter ip6_tables iptable_mangle cls_matchall nfnetlink_cttimeout act_gact cls_flower sch_ingress vhost_iotlb iptable_raw tunnel6 vfio_iommu_type1 vfio openvswitch nsh rpcsec_gss_krb5 auth_rpcgss oid_registry xt_conntrack xt_MASQUERADE nf_conntrack_netlink nfnetlink iptable_nat nf_nat xt_addrtype br_netfilter overlay zram zsmalloc rpcrdma ib_iser libiscsi scsi_transport_iscsi rdma_cm iw_cm ib_cm ib_core fuse [last unloaded: nf_tables]\n    CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.13.0-rc5_for_upstream_min_debug_2024_12_30_21_33 #1\n    Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014\n    RIP: 0010:iommu_dma_unmap_page+0x79/0x90\n    Code: 2b 4d 3b 21 72 26 4d 3b 61 08 73 20 49 89 d8 44 89 f9 5b 4c 89 f2 4c 89 e6 48 89 ef 5d 41 5c 41 5d 41 5e 41 5f e9 c7 ae 9e ff \u003c0f\u003e 0b 5b 5d 41 5c 41 5d 41 5e 41 5f c3 66 2e 0f 1f 84 00 00 00 00\n    Call Trace:\n     \u003cIRQ\u003e\n     ? __warn+0x7d/0x110\n     ? iommu_dma_unmap_page+0x79/0x90\n     ? report_bug+0x16d/0x180\n     ? handle_bug+0x4f/0x90\n     ? exc_invalid_op+0x14/0x70\n     ? asm_exc_invalid_op+0x16/0x20\n     ? iommu_dma_unmap_page+0x79/0x90\n     ? iommu_dma_unmap_page+0x2e/0x90\n     dma_unmap_page_attrs+0x10d/0x1b0\n     mlx5e_tx_wi_dma_unmap+0xbe/0x120 [mlx5_core]\n     mlx5e_poll_tx_cq+0x16d/0x690 [mlx5_core]\n     mlx5e_napi_poll+0x8b/0xac0 [mlx5_core]\n     __napi_poll+0x24/0x190\n     net_rx_action+0x32a/0x3b0\n     ? mlx5_eq_comp_int+0x7e/0x270 [mlx5_core]\n     ? notifier_call_chain+0x35/0xa0\n     handle_softirqs+0xc9/0x270\n     irq_exit_rcu+0x71/0xd0\n     common_interrupt+0x7f/0xa0\n     \u003c/IRQ\u003e\n     \u003cTASK\u003e\n     asm_common_interrupt+0x22/0x40","modified":"2026-06-18T03:55:27.216440984Z","published":"2026-05-08T14:22:27.513Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/43xxx/CVE-2026-43466.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/1633111d69053512d099658d4a05fc736fab36b0"},{"type":"WEB","url":"https://git.kernel.org/stable/c/383b37c04a4827ba60b2bafc1a6cdfd995aed58f"},{"type":"WEB","url":"https://git.kernel.org/stable/c/6eb68ecc5acc3b319986566c595990b8a7265b23"},{"type":"WEB","url":"https://git.kernel.org/stable/c/6f41f7812bfa7f991b732a4b45c5c52fc4be3b4e"},{"type":"WEB","url":"https://git.kernel.org/stable/c/821f85d619f7f22cda7b9d7de89cf5eeb1d11544"},{"type":"WEB","url":"https://git.kernel.org/stable/c/829efcccfa8f69db5dc8332961295587d218cee6"},{"type":"WEB","url":"https://git.kernel.org/stable/c/9c5ee9b981ee050b73fdf3f4a2464d6f1a8e10a8"},{"type":"WEB","url":"https://git.kernel.org/stable/c/ce1b19dd0684eeb68a124c11085bd611260b36d9"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/43xxx/CVE-2026-43466.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-43466"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"db75373c91b0cfb6a68ad6ae88721e4e21ae6261"},{"fixed":"821f85d619f7f22cda7b9d7de89cf5eeb1d11544"},{"fixed":"6eb68ecc5acc3b319986566c595990b8a7265b23"},{"fixed":"6f41f7812bfa7f991b732a4b45c5c52fc4be3b4e"},{"fixed":"383b37c04a4827ba60b2bafc1a6cdfd995aed58f"},{"fixed":"9c5ee9b981ee050b73fdf3f4a2464d6f1a8e10a8"},{"fixed":"ce1b19dd0684eeb68a124c11085bd611260b36d9"},{"fixed":"829efcccfa8f69db5dc8332961295587d218cee6"},{"fixed":"1633111d69053512d099658d4a05fc736fab36b0"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-43466.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.17.0"},{"fixed":"5.10.253"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.15.203"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.167"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.130"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.78"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.19"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"6.19.9"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-43466.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H"}]}