{
   "containers": {
      "cna": {
         "providerMetadata": {
            "orgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038"
         },
         "descriptions": [
            {
               "lang": "en",
               "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/mlx5e: Avoid field-overflowing memcpy()\n\nIn preparation for FORTIFY_SOURCE performing compile-time and run-time\nfield bounds checking for memcpy(), memmove(), and memset(), avoid\nintentionally writing across neighboring fields.\n\nUse flexible arrays instead of zero-element arrays (which look like they\nare always overflowing) and split the cross-field memcpy() into two halves\nthat can be appropriately bounds-checked by the compiler.\n\nWe were doing:\n\n\t#define ETH_HLEN  14\n\t#define VLAN_HLEN  4\n\t...\n\t#define MLX5E_XDP_MIN_INLINE (ETH_HLEN + VLAN_HLEN)\n\t...\n        struct mlx5e_tx_wqe      *wqe  = mlx5_wq_cyc_get_wqe(wq, pi);\n\t...\n        struct mlx5_wqe_eth_seg  *eseg = &wqe->eth;\n        struct mlx5_wqe_data_seg *dseg = wqe->data;\n\t...\n\tmemcpy(eseg->inline_hdr.start, xdptxd->data, MLX5E_XDP_MIN_INLINE);\n\ntarget is wqe->eth.inline_hdr.start (which the compiler sees as being\n2 bytes in size), but copying 18, intending to write across start\n(really vlan_tci, 2 bytes). The remaining 16 bytes get written into\nwqe->data[0], covering byte_count (4 bytes), lkey (4 bytes), and addr\n(8 bytes).\n\nstruct mlx5e_tx_wqe {\n        struct mlx5_wqe_ctrl_seg   ctrl;                 /*     0    16 */\n        struct mlx5_wqe_eth_seg    eth;                  /*    16    16 */\n        struct mlx5_wqe_data_seg   data[];               /*    32     0 */\n\n        /* size: 32, cachelines: 1, members: 3 */\n        /* last cacheline: 32 bytes */\n};\n\nstruct mlx5_wqe_eth_seg {\n        u8                         swp_outer_l4_offset;  /*     0     1 */\n        u8                         swp_outer_l3_offset;  /*     1     1 */\n        u8                         swp_inner_l4_offset;  /*     2     1 */\n        u8                         swp_inner_l3_offset;  /*     3     1 */\n        u8                         cs_flags;             /*     4     1 */\n        u8                         swp_flags;            /*     5     1 */\n        __be16                     mss;                  /*     6     2 */\n        __be32                     flow_table_metadata;  /*     8     4 */\n        union {\n                struct {\n                        __be16     sz;                   /*    12     2 */\n                        u8         start[2];             /*    14     2 */\n                } inline_hdr;                            /*    12     4 */\n                struct {\n                        __be16     type;                 /*    12     2 */\n                        __be16     vlan_tci;             /*    14     2 */\n                } insert;                                /*    12     4 */\n                __be32             trailer;              /*    12     4 */\n        };                                               /*    12     4 */\n\n        /* size: 16, cachelines: 1, members: 9 */\n        /* last cacheline: 16 bytes */\n};\n\nstruct mlx5_wqe_data_seg {\n        __be32                     byte_count;           /*     0     4 */\n        __be32                     lkey;                 /*     4     4 */\n        __be64                     addr;                 /*     8     8 */\n\n        /* size: 16, cachelines: 1, members: 3 */\n        /* last cacheline: 16 bytes */\n};\n\nSo, split the memcpy() so the compiler can reason about the buffer\nsizes.\n\n\"pahole\" shows no size nor member offset changes to struct mlx5e_tx_wqe\nnor struct mlx5e_umr_wqe. \"objdump -d\" shows no meaningful object\ncode changes (i.e. only source line number induced differences and\noptimizations)."
            }
         ],
         "affected": [
            {
               "product": "Linux",
               "vendor": "Linux",
               "defaultStatus": "unaffected",
               "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
               "programFiles": [
                  "drivers/net/ethernet/mellanox/mlx5/core/en.h",
                  "drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c"
               ],
               "versions": [
                  {
                     "version": "b5503b994ed5",
                     "lessThan": "8fbdf8c8b8ab",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "b5503b994ed5",
                     "lessThan": "ad5185735f7d",
                     "status": "affected",
                     "versionType": "git"
                  }
               ]
            },
            {
               "product": "Linux",
               "vendor": "Linux",
               "defaultStatus": "affected",
               "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
               "programFiles": [
                  "drivers/net/ethernet/mellanox/mlx5/core/en.h",
                  "drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c"
               ],
               "versions": [
                  {
                     "version": "4.9",
                     "status": "affected"
                  },
                  {
                     "version": "0",
                     "lessThan": "4.9",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "5.16.6",
                     "lessThanOrEqual": "5.16.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "5.17",
                     "lessThanOrEqual": "*",
                     "status": "unaffected",
                     "versionType": "original_commit_for_fix"
                  }
               ]
            }
         ],
         "references": [
            {
               "url": "https://git.kernel.org/stable/c/8fbdf8c8b8ab82beab882175157650452c46493e"
            },
            {
               "url": "https://git.kernel.org/stable/c/ad5185735f7dab342fdd0dd41044da4c9ccfef67"
            }
         ],
         "title": "net/mlx5e: Avoid field-overflowing memcpy()",
         "x_generator": {
            "engine": "bippy-7d53e8ef8be4"
         }
      }
   },
   "cveMetadata": {
      "assignerOrgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038",
      "cveID": "CVE-2022-48744",
      "requesterUserId": "gregkh@kernel.org",
      "serial": "1",
      "state": "PUBLISHED"
   },
   "dataType": "CVE_RECORD",
   "dataVersion": "5.0"
}