{
   "containers": {
      "cna": {
         "providerMetadata": {
            "orgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038"
         },
         "descriptions": [
            {
               "lang": "en",
               "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nocfs2: fix race between searching chunks and release journal_head from buffer_head\n\nEncountered a race between ocfs2_test_bg_bit_allocatable() and\njbd2_journal_put_journal_head() resulting in the below vmcore.\n\n  PID: 106879  TASK: ffff880244ba9c00  CPU: 2   COMMAND: \"loop3\"\n  Call trace:\n    panic\n    oops_end\n    no_context\n    __bad_area_nosemaphore\n    bad_area_nosemaphore\n    __do_page_fault\n    do_page_fault\n    page_fault\n      [exception RIP: ocfs2_block_group_find_clear_bits+316]\n    ocfs2_block_group_find_clear_bits [ocfs2]\n    ocfs2_cluster_group_search [ocfs2]\n    ocfs2_search_chain [ocfs2]\n    ocfs2_claim_suballoc_bits [ocfs2]\n    __ocfs2_claim_clusters [ocfs2]\n    ocfs2_claim_clusters [ocfs2]\n    ocfs2_local_alloc_slide_window [ocfs2]\n    ocfs2_reserve_local_alloc_bits [ocfs2]\n    ocfs2_reserve_clusters_with_limit [ocfs2]\n    ocfs2_reserve_clusters [ocfs2]\n    ocfs2_lock_refcount_allocators [ocfs2]\n    ocfs2_make_clusters_writable [ocfs2]\n    ocfs2_replace_cow [ocfs2]\n    ocfs2_refcount_cow [ocfs2]\n    ocfs2_file_write_iter [ocfs2]\n    lo_rw_aio\n    loop_queue_work\n    kthread_worker_fn\n    kthread\n    ret_from_fork\n\nWhen ocfs2_test_bg_bit_allocatable() called bh2jh(bg_bh), the\nbg_bh->b_private NULL as jbd2_journal_put_journal_head() raced and\nreleased the jounal head from the buffer head.  Needed to take bit lock\nfor the bit 'BH_JournalHead' to fix this race."
            }
         ],
         "affected": [
            {
               "product": "Linux",
               "vendor": "Linux",
               "defaultStatus": "unaffected",
               "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
               "programFiles": [
                  "fs/ocfs2/suballoc.c"
               ],
               "versions": [
                  {
                     "version": "1da177e4c3f4",
                     "lessThan": "5043fbd294f5",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "1da177e4c3f4",
                     "lessThan": "2e382600e885",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "1da177e4c3f4",
                     "lessThan": "6f1b228529ae",
                     "status": "affected",
                     "versionType": "git"
                  }
               ]
            },
            {
               "product": "Linux",
               "vendor": "Linux",
               "defaultStatus": "affected",
               "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
               "programFiles": [
                  "fs/ocfs2/suballoc.c"
               ],
               "versions": [
                  {
                     "version": "5.10.77",
                     "lessThanOrEqual": "5.10.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "5.14.16",
                     "lessThanOrEqual": "5.14.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "5.15",
                     "lessThanOrEqual": "*",
                     "status": "unaffected",
                     "versionType": "original_commit_for_fix"
                  }
               ]
            }
         ],
         "references": [
            {
               "url": "https://git.kernel.org/stable/c/5043fbd294f5909a080ade0f04b70a4da9e122b7"
            },
            {
               "url": "https://git.kernel.org/stable/c/2e382600e8856ea654677b5134ee66e03ea72bc2"
            },
            {
               "url": "https://git.kernel.org/stable/c/6f1b228529ae49b0f85ab89bcdb6c365df401558"
            }
         ],
         "title": "ocfs2: fix race between searching chunks and release journal_head from buffer_head",
         "x_generator": {
            "engine": "bippy-a5840b7849dd"
         }
      }
   },
   "cveMetadata": {
      "assignerOrgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038",
      "cveID": "CVE-2021-47493",
      "requesterUserId": "gregkh@kernel.org",
      "serial": "1",
      "state": "PUBLISHED"
   },
   "dataType": "CVE_RECORD",
   "dataVersion": "5.0"
}