{
   "containers": {
      "cna": {
         "providerMetadata": {
            "orgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038"
         },
         "descriptions": [
            {
               "lang": "en",
               "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nRDMA/mlx5: Fix releasing unallocated memory in dereg MR flow\n\nFor the case of IB_MR_TYPE_DM the mr does doesn't have a umem, even though\nit is a user MR. This causes function mlx5_free_priv_descs() to think that\nit is a kernel MR, leading to wrongly accessing mr->descs that will get\nwrong values in the union which leads to attempt to release resources that\nwere not allocated in the first place.\n\nFor example:\n DMA-API: mlx5_core 0000:08:00.1: device driver tries to free DMA memory it has not allocated [device address=0x0000000000000000] [size=0 bytes]\n WARNING: CPU: 8 PID: 1021 at kernel/dma/debug.c:961 check_unmap+0x54f/0x8b0\n RIP: 0010:check_unmap+0x54f/0x8b0\n Call Trace:\n  debug_dma_unmap_page+0x57/0x60\n  mlx5_free_priv_descs+0x57/0x70 [mlx5_ib]\n  mlx5_ib_dereg_mr+0x1fb/0x3d0 [mlx5_ib]\n  ib_dereg_mr_user+0x60/0x140 [ib_core]\n  uverbs_destroy_uobject+0x59/0x210 [ib_uverbs]\n  uobj_destroy+0x3f/0x80 [ib_uverbs]\n  ib_uverbs_cmd_verbs+0x435/0xd10 [ib_uverbs]\n  ? uverbs_finalize_object+0x50/0x50 [ib_uverbs]\n  ? lock_acquire+0xc4/0x2e0\n  ? lock_acquired+0x12/0x380\n  ? lock_acquire+0xc4/0x2e0\n  ? lock_acquire+0xc4/0x2e0\n  ? ib_uverbs_ioctl+0x7c/0x140 [ib_uverbs]\n  ? lock_release+0x28a/0x400\n  ib_uverbs_ioctl+0xc0/0x140 [ib_uverbs]\n  ? ib_uverbs_ioctl+0x7c/0x140 [ib_uverbs]\n  __x64_sys_ioctl+0x7f/0xb0\n  do_syscall_64+0x38/0x90\n\nFix it by reorganizing the dereg flow and mlx5_ib_mr structure:\n - Move the ib_umem field into the user MRs structure in the union as it's\n   applicable only there.\n - Function mlx5_ib_dereg_mr() will now call mlx5_free_priv_descs() only\n   in case there isn't udata, which indicates that this isn't a user MR."
            }
         ],
         "affected": [
            {
               "product": "Linux",
               "vendor": "Linux",
               "defaultStatus": "unaffected",
               "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
               "programFiles": [
                  "drivers/infiniband/hw/mlx5/mlx5_ib.h",
                  "drivers/infiniband/hw/mlx5/mr.c"
               ],
               "versions": [
                  {
                     "version": "f18ec4223117",
                     "lessThan": "e3bc4d4b50ca",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "f18ec4223117",
                     "lessThan": "c44979ace49b",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "f18ec4223117",
                     "lessThan": "f0ae4afe3d35",
                     "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/infiniband/hw/mlx5/mlx5_ib.h",
                  "drivers/infiniband/hw/mlx5/mr.c"
               ],
               "versions": [
                  {
                     "version": "5.13",
                     "status": "affected"
                  },
                  {
                     "version": "0",
                     "lessThan": "5.13",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "5.15.10",
                     "lessThanOrEqual": "5.15.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "5.15.14",
                     "lessThanOrEqual": "5.15.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "5.16",
                     "lessThanOrEqual": "*",
                     "status": "unaffected",
                     "versionType": "original_commit_for_fix"
                  }
               ]
            }
         ],
         "references": [
            {
               "url": "https://git.kernel.org/stable/c/e3bc4d4b50cae7db08e50dbe43f771c906e97701"
            },
            {
               "url": "https://git.kernel.org/stable/c/c44979ace49b4aede3cc7cb5542316e53a4005c9"
            },
            {
               "url": "https://git.kernel.org/stable/c/f0ae4afe3d35e67db042c58a52909e06262b740f"
            }
         ],
         "title": "RDMA/mlx5: Fix releasing unallocated memory in dereg MR flow",
         "x_generator": {
            "engine": "bippy-a5840b7849dd"
         }
      }
   },
   "cveMetadata": {
      "assignerOrgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038",
      "cveID": "CVE-2021-47615",
      "requesterUserId": "gregkh@kernel.org",
      "serial": "1",
      "state": "PUBLISHED"
   },
   "dataType": "CVE_RECORD",
   "dataVersion": "5.0"
}