{"id":"CVE-2026-72341","title":"net/mlx5e: Fix publication race for priv->channel_stats[]","summary":"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_nc…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= fa691d0c9c0812b9045f3a9420862e47b3b92518 < 268869794170af37727816ad02051808adb9c9c3","Linux >= fa691d0c9c0812b9045f3a9420862e47b3b92518 < acd34d24342a28794e706ce8191ca6c3114a38ae","Linux >= fa691d0c9c0812b9045f3a9420862e47b3b92518 < 5c7e3755abf663f033de24f917b77685e9543045","Linux >= fa691d0c9c0812b9045f3a9420862e47b3b92518 < 815515ec68f527ca755cb1e2c1ff9148f6b3ea56","Linux >= fa691d0c9c0812b9045f3a9420862e47b3b92518 < 5a799714e8ca0bce9ea40694f49914cf1adbbaa9","Linux 5.17"],"published":"2026-08-15","updated":"2026-10-21","sourceUpdated":"2026-10-21T12:44:38.498Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-72341","references":[{"url":"https://git.kernel.org/stable/c/268869794170af37727816ad02051808adb9c9c3"},{"url":"https://git.kernel.org/stable/c/acd34d24342a28794e706ce8191ca6c3114a38ae"},{"url":"https://git.kernel.org/stable/c/5c7e3755abf663f033de24f917b77685e9543045"},{"url":"https://git.kernel.org/stable/c/815515ec68f527ca755cb1e2c1ff9148f6b3ea56"},{"url":"https://git.kernel.org/stable/c/5a799714e8ca0bce9ea40694f49914cf1adbbaa9"}],"tags":["cve.org"],"epss":0.00206,"epssPercentile":0.10126,"ingestedAt":"2026-10-21T12:48:53.591Z","slug":"CVE-2026-72341","body":"## Overview\n\nIn 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.\n\n## Affected\n\n- `Linux >= fa691d0c9c0812b9045f3a9420862e47b3b92518 < 268869794170af37727816ad02051808adb9c9c3`\n- `Linux >= fa691d0c9c0812b9045f3a9420862e47b3b92518 < acd34d24342a28794e706ce8191ca6c3114a38ae`\n- `Linux >= fa691d0c9c0812b9045f3a9420862e47b3b92518 < 5c7e3755abf663f033de24f917b77685e9543045`\n- `Linux >= fa691d0c9c0812b9045f3a9420862e47b3b92518 < 815515ec68f527ca755cb1e2c1ff9148f6b3ea56`\n- `Linux >= fa691d0c9c0812b9045f3a9420862e47b3b92518 < 5a799714e8ca0bce9ea40694f49914cf1adbbaa9`\n- `Linux 5.17`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}