{
   "containers": {
      "cna": {
         "providerMetadata": {
            "orgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038"
         },
         "descriptions": [
            {
               "lang": "en",
               "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nworkqueue: Fix spruious data race in __flush_work()\n\nWhen flushing a work item for cancellation, __flush_work() knows that it\nexclusively owns the work item through its PENDING bit. 134874e2eee9\n(\"workqueue: Allow cancel_work_sync() and disable_work() from atomic\ncontexts on BH work items\") added a read of @work->data to determine whether\nto use busy wait for BH work items that are being canceled. While the read\nis safe when @from_cancel, @work->data was read before testing @from_cancel\nto simplify code structure:\n\n\tdata = *work_data_bits(work);\n\tif (from_cancel &&\n\t    !WARN_ON_ONCE(data & WORK_STRUCT_PWQ) && (data & WORK_OFFQ_BH)) {\n\nWhile the read data was never used if !@from_cancel, this could trigger\nKCSAN data race detection spuriously:\n\n  ==================================================================\n  BUG: KCSAN: data-race in __flush_work / __flush_work\n\n  write to 0xffff8881223aa3e8 of 8 bytes by task 3998 on cpu 0:\n   instrument_write include/linux/instrumented.h:41 [inline]\n   ___set_bit include/asm-generic/bitops/instrumented-non-atomic.h:28 [inline]\n   insert_wq_barrier kernel/workqueue.c:3790 [inline]\n   start_flush_work kernel/workqueue.c:4142 [inline]\n   __flush_work+0x30b/0x570 kernel/workqueue.c:4178\n   flush_work kernel/workqueue.c:4229 [inline]\n   ...\n\n  read to 0xffff8881223aa3e8 of 8 bytes by task 50 on cpu 1:\n   __flush_work+0x42a/0x570 kernel/workqueue.c:4188\n   flush_work kernel/workqueue.c:4229 [inline]\n   flush_delayed_work+0x66/0x70 kernel/workqueue.c:4251\n   ...\n\n  value changed: 0x0000000000400000 -> 0xffff88810006c00d\n\nReorganize the code so that @from_cancel is tested before @work->data is\naccessed. The only problem is triggering KCSAN detection spuriously. This\nshouldn't need READ_ONCE() or other access qualifiers.\n\nNo functional changes."
            }
         ],
         "affected": [
            {
               "product": "Linux",
               "vendor": "Linux",
               "defaultStatus": "unaffected",
               "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
               "programFiles": [
                  "kernel/workqueue.c"
               ],
               "versions": [
                  {
                     "version": "134874e2eee9",
                     "lessThan": "91d09642127a",
                     "status": "affected",
                     "versionType": "git"
                  },
                  {
                     "version": "134874e2eee9",
                     "lessThan": "8bc35475ef1a",
                     "status": "affected",
                     "versionType": "git"
                  }
               ]
            },
            {
               "product": "Linux",
               "vendor": "Linux",
               "defaultStatus": "affected",
               "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
               "programFiles": [
                  "kernel/workqueue.c"
               ],
               "versions": [
                  {
                     "version": "6.10",
                     "status": "affected"
                  },
                  {
                     "version": "0",
                     "lessThan": "6.10",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "6.10.7",
                     "lessThanOrEqual": "6.10.*",
                     "status": "unaffected",
                     "versionType": "custom"
                  },
                  {
                     "version": "6.11",
                     "lessThanOrEqual": "*",
                     "status": "unaffected",
                     "versionType": "original_commit_for_fix"
                  }
               ]
            }
         ],
         "references": [
            {
               "url": "https://git.kernel.org/stable/c/91d09642127a32fde231face2ff489af70eef316"
            },
            {
               "url": "https://git.kernel.org/stable/c/8bc35475ef1a23b0e224f3242eb11c76cab0ea88"
            }
         ],
         "title": "workqueue: Fix spruious data race in __flush_work()",
         "x_generator": {
            "engine": "bippy-c9c4e1df01b2"
         }
      }
   },
   "cveMetadata": {
      "assignerOrgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038",
      "cveID": "CVE-2024-46704",
      "requesterUserId": "gregkh@kernel.org",
      "serial": "1",
      "state": "PUBLISHED"
   },
   "dataType": "CVE_RECORD",
   "dataVersion": "5.0"
}
