{"cve":"CVE-2024-46704","nvd":{"published":"2024-09-13T07:15:05.397","modified":"2026-06-17T07:55:45.800","status":"Analyzed","description":"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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H","score":4.7},"cwes":[],"references":["https://git.kernel.org/stable/c/8bc35475ef1a23b0e224f3242eb11c76cab0ea88","https://git.kernel.org/stable/c/91d09642127a32fde231face2ff489af70eef316"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T21:54:38.012257375+00:00"},"epss":{"cve":"CVE-2024-46704","score":0.00175,"percentile":0.06983,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}