{"id":"CVE-2026-64253","state":"PUBLISHED","title":"kernel/fork: clear PF_BLOCK_TS in copy_process()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nkernel/fork: clear PF_BLOCK_TS in copy_process()\n\nPF_BLOCK_TS is only set in blk_time_get_ns() when current->plug is\nnon-NULL, and blk_finish_plug() clears it via __blk_flush_plug()\nbefore NULLing the plug pointer.  copy_process() breaks the\ninvariant by inheriting PF_BLOCK_TS from the parent while resetting\nthe child's plug to NULL.\n\nClear PF_BLOCK_TS alongside that assignment so callers can rely on\n\"PF_BLOCK_TS set implies current->plug != NULL\" and dereference\ncurrent->plug unguarded.","publishedAt":"2026-07-24T15:31:21.378Z","updatedAt":"2026-08-17T04:52:05.134Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"06b23f92af87a84d70881b2ecaa72e00f7838264","status":"affected","lessThan":"ee0801aceabdf583392477baf69a290b09448b8f","versionType":"git"},{"version":"06b23f92af87a84d70881b2ecaa72e00f7838264","status":"affected","lessThan":"99e6c712cc300883b8cbf03347d5359ec1a4d6dd","versionType":"git"},{"version":"06b23f92af87a84d70881b2ecaa72e00f7838264","status":"affected","lessThan":"77bba61a20f1b3d206f4f90e10a7bb3cd90b9619","versionType":"git"},{"version":"06b23f92af87a84d70881b2ecaa72e00f7838264","status":"affected","lessThan":"fd38b75c4b43295b10d69772a46d1c74dbd6fc81","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/fork.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.9","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.9","versionType":"semver"},{"version":"6.12.95","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.38","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.3","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/fork.c"]}],"references":["https://git.kernel.org/stable/c/ee0801aceabdf583392477baf69a290b09448b8f","https://git.kernel.org/stable/c/99e6c712cc300883b8cbf03347d5359ec1a4d6dd","https://git.kernel.org/stable/c/77bba61a20f1b3d206f4f90e10a7bb3cd90b9619","https://git.kernel.org/stable/c/fd38b75c4b43295b10d69772a46d1c74dbd6fc81"],"weaknesses":[],"ingestedAt":"2026-10-29T20:12:41.951Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/64xxx/CVE-2026-64253.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-64253","state":"PUBLISHED","datePublished":"2026-07-24T15:31:21.378Z","dateUpdated":"2026-08-17T04:52:05.134Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-07-19T15:36:31.773Z"},"containers":{"cna":{"title":"kernel/fork: clear PF_BLOCK_TS in copy_process()","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nkernel/fork: clear PF_BLOCK_TS in copy_process()\n\nPF_BLOCK_TS is only set in blk_time_get_ns() when current->plug is\nnon-NULL, and blk_finish_plug() clears it via __blk_flush_plug()\nbefore NULLing the plug pointer.  copy_process() breaks the\ninvariant by inheriting PF_BLOCK_TS from the parent while resetting\nthe child's plug to NULL.\n\nClear PF_BLOCK_TS alongside that assignment so callers can rely on\n\"PF_BLOCK_TS set implies current->plug != NULL\" and dereference\ncurrent->plug unguarded."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"06b23f92af87a84d70881b2ecaa72e00f7838264","status":"affected","lessThan":"ee0801aceabdf583392477baf69a290b09448b8f","versionType":"git"},{"version":"06b23f92af87a84d70881b2ecaa72e00f7838264","status":"affected","lessThan":"99e6c712cc300883b8cbf03347d5359ec1a4d6dd","versionType":"git"},{"version":"06b23f92af87a84d70881b2ecaa72e00f7838264","status":"affected","lessThan":"77bba61a20f1b3d206f4f90e10a7bb3cd90b9619","versionType":"git"},{"version":"06b23f92af87a84d70881b2ecaa72e00f7838264","status":"affected","lessThan":"fd38b75c4b43295b10d69772a46d1c74dbd6fc81","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/fork.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.9","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.9","versionType":"semver"},{"version":"6.12.95","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.38","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.3","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/fork.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/ee0801aceabdf583392477baf69a290b09448b8f"},{"url":"https://git.kernel.org/stable/c/99e6c712cc300883b8cbf03347d5359ec1a4d6dd"},{"url":"https://git.kernel.org/stable/c/77bba61a20f1b3d206f4f90e10a7bb3cd90b9619"},{"url":"https://git.kernel.org/stable/c/fd38b75c4b43295b10d69772a46d1c74dbd6fc81"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-17T04:52:05.134Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.9","versionEndExcluding":"6.12.95"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.9","versionEndExcluding":"6.18.38"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.9","versionEndExcluding":"7.1.3"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.9","versionEndExcluding":"7.2"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}