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CVE-2026-72341

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: net/mlx5e: Fix publication race for priv->channel_stats[] mlx5e_channel_stats_alloc() publishes a new entry to priv->channel_stats[] and then increments priv->stats_nch as a publication token, but neither store carries any memory barrier: priv->channel_stats[ix] = kvzalloc_node(...); if (!priv->channel_stats[ix]) return -ENOMEM; priv->stats_nch++; Concurrent readers compute the loop bound from priv->stats_nch and then dereference priv->channel_stats[i] using plain accesses, e.g. for (i = 0; i < priv->stats_nch; i++) { struct mlx5e_channel_stats *cs = priv->channel_stats[i]; ... cs->rq.packets ... } On weakly-ordered architectures (ARM, PowerPC, RISC-V) the writes to channel_stats[ix] and stats_nch may become visible to other CPUs out of program order. A reader can observe stats_nch == N while still seeing channel_stats[N-1] == NULL, leading to a NULL pointer dereference in the channel_stats loop. This has been observed in production on BlueField-3 DPUs (arm64), where ovs-vswitchd queries netdev statistics over netlink during NIC bringup, racing mlx5e_open_channel() -> mlx5e_channel_stats_alloc() on another CPU: Unable to handle kernel NULL pointer dereference at virtual address 0x840 Hardware name: BlueField-3 DPU pc : mlx5e_fold_sw_stats64+0x30/0x180 [mlx5_core] Call trace: mlx5e_fold_sw_stats64+0x30/0x180 [mlx5_core] dev_get_stats+0x50/0xc0 ovs_vport_get_stats+0x38/0xac [openvswitch] ovs_vport_cmd_fill_info+0x194/0x290 [openvswitch] ovs_vport_cmd_get+0xbc/0x10c [openvswitch] genl_family_rcv_msg_doit+0xd0/0x160 genl_rcv_msg+0xec/0x1f0 netlink_rcv_skb+0x64/0x130 genl_rcv+0x40/0x60 netlink_unicast+0x2fc/0x370 netlink_sendmsg+0x1dc/0x454 ... __arm64_sys_sendmsg+0x2c/0x40 Add mlx5e_stats_nch_write() and mlx5e_stats_nch_read() helpers in en.h that wrap the smp_store_release()/smp_load_acquire() pair on stats_nch. The release/acquire pair establishes the contract: stats_nch == N => channel_stats[0..N-1] are visible and non-NULL. Publish the stats_nch increment via mlx5e_stats_nch_write() in the writer (mlx5e_channel_stats_alloc()), and read stats_nch via mlx5e_stats_nch_read() in all readers: mlx5e RX/TX queue stats, mlx5e_get_base_stats(), ethtool channels stats, IPoIB stats, the sw_stats fold and the HV VHCA stats agent.

Severity
Not scored
CVSS score
Not available
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-08-15 06:22:07.403000
Last modified
2026-10-30 13:19:50.050000
View original CVE JSON
{
  "id": "CVE-2026-72341",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-08-15T06:22:07.403",
  "lastModified": "2026-10-30T13:19:50.050",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/mlx5e: Fix publication race for priv->channel_stats[]\n\nmlx5e_channel_stats_alloc() publishes a new entry to\npriv->channel_stats[] and then increments priv->stats_nch as a\npublication token, but neither store carries any memory barrier:\n\n\tpriv->channel_stats[ix] = kvzalloc_node(...);\n\tif (!priv->channel_stats[ix])\n\t\treturn -ENOMEM;\n\tpriv->stats_nch++;\n\nConcurrent readers compute the loop bound from priv->stats_nch and\nthen dereference priv->channel_stats[i] using plain accesses, e.g.\n\n\tfor (i = 0; i < priv->stats_nch; i++) {\n\t\tstruct mlx5e_channel_stats *cs = priv->channel_stats[i];\n\t\t... cs->rq.packets ...\n\t}\n\nOn weakly-ordered architectures (ARM, PowerPC, RISC-V) the writes to\nchannel_stats[ix] and stats_nch may become visible to other CPUs out\nof program order. A reader can observe stats_nch == N while still\nseeing channel_stats[N-1] == NULL, leading to a NULL pointer\ndereference in the channel_stats loop.\n\nThis has been observed in production on BlueField-3 DPUs (arm64),\nwhere ovs-vswitchd queries netdev statistics over netlink during NIC\nbringup, racing mlx5e_open_channel() -> mlx5e_channel_stats_alloc()\non another CPU:\n\n  Unable to handle kernel NULL pointer dereference at virtual address 0x840\n  Hardware name: BlueField-3 DPU\n  pc : mlx5e_fold_sw_stats64+0x30/0x180 [mlx5_core]\n  Call trace:\n   mlx5e_fold_sw_stats64+0x30/0x180 [mlx5_core]\n   dev_get_stats+0x50/0xc0\n   ovs_vport_get_stats+0x38/0xac [openvswitch]\n   ovs_vport_cmd_fill_info+0x194/0x290 [openvswitch]\n   ovs_vport_cmd_get+0xbc/0x10c [openvswitch]\n   genl_family_rcv_msg_doit+0xd0/0x160\n   genl_rcv_msg+0xec/0x1f0\n   netlink_rcv_skb+0x64/0x130\n   genl_rcv+0x40/0x60\n   netlink_unicast+0x2fc/0x370\n   netlink_sendmsg+0x1dc/0x454\n   ...\n   __arm64_sys_sendmsg+0x2c/0x40\n\nAdd mlx5e_stats_nch_write() and mlx5e_stats_nch_read() helpers in en.h\nthat wrap the smp_store_release()/smp_load_acquire() pair on stats_nch.\nThe release/acquire pair establishes the contract:\n\n  stats_nch == N  =>  channel_stats[0..N-1] are visible and non-NULL.\n\nPublish the stats_nch increment via mlx5e_stats_nch_write() in the\nwriter (mlx5e_channel_stats_alloc()), and read stats_nch via\nmlx5e_stats_nch_read() in all readers: mlx5e RX/TX queue stats,\nmlx5e_get_base_stats(), ethtool channels stats, IPoIB stats, the\nsw_stats fold and the HV VHCA stats agent."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "drivers/net/ethernet/mellanox/mlx5/core/en.h",
            "drivers/net/ethernet/mellanox/mlx5/core/en/hv_vhca_stats.c",
            "drivers/net/ethernet/mellanox/mlx5/core/en_main.c",
            "drivers/net/ethernet/mellanox/mlx5/core/en_stats.c",
            "drivers/net/ethernet/mellanox/mlx5/core/ipoib/ipoib.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "fa691d0c9c0812b9045f3a9420862e47b3b92518",
              "lessThan": "df122c593735aa5e1c97457767aa10ed8fa972e0",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "fa691d0c9c0812b9045f3a9420862e47b3b92518",
              "lessThan": "268869794170af37727816ad02051808adb9c9c3",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "fa691d0c9c0812b9045f3a9420862e47b3b92518",
              "lessThan": "acd34d24342a28794e706ce8191ca6c3114a38ae",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "fa691d0c9c0812b9045f3a9420862e47b3b92518",
              "lessThan": "5c7e3755abf663f033de24f917b77685e9543045",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "fa691d0c9c0812b9045f3a9420862e47b3b92518",
              "lessThan": "815515ec68f527ca755cb1e2c1ff9148f6b3ea56",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "fa691d0c9c0812b9045f3a9420862e47b3b92518",
              "lessThan": "5a799714e8ca0bce9ea40694f49914cf1adbbaa9",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "drivers/net/ethernet/mellanox/mlx5/core/en.h",
            "drivers/net/ethernet/mellanox/mlx5/core/en/hv_vhca_stats.c",
            "drivers/net/ethernet/mellanox/mlx5/core/en_main.c",
            "drivers/net/ethernet/mellanox/mlx5/core/en_stats.c",
            "drivers/net/ethernet/mellanox/mlx5/core/ipoib/ipoib.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "5.17",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "5.17",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.1.191",
              "lessThanOrEqual": "6.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.6.160",
              "lessThanOrEqual": "6.6.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.114",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.40",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.1.5",
              "lessThanOrEqual": "7.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {},
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/268869794170af37727816ad02051808adb9c9c3",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/5a799714e8ca0bce9ea40694f49914cf1adbbaa9",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/5c7e3755abf663f033de24f917b77685e9543045",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/815515ec68f527ca755cb1e2c1ff9148f6b3ea56",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/acd34d24342a28794e706ce8191ca6c3114a38ae",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/df122c593735aa5e1c97457767aa10ed8fa972e0",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}