{"dataType":"CVE_RECORD","dataVersion":"5.1","cveMetadata":{"cveId":"CVE-2021-47189","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2024-03-25T09:12:14.113Z","datePublished":"2024-04-10T18:56:28.194Z","dateUpdated":"2025-05-04T07:06:01.389Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2025-05-04T07:06:01.389Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nbtrfs: fix memory ordering between normal and ordered work functions\n\nOrdered work functions aren't guaranteed to be handled by the same thread\nwhich executed the normal work functions. The only way execution between\nnormal/ordered functions is synchronized is via the WORK_DONE_BIT,\nunfortunately the used bitops don't guarantee any ordering whatsoever.\n\nThis manifested as seemingly inexplicable crashes on ARM64, where\nasync_chunk::inode is seen as non-null in async_cow_submit which causes\nsubmit_compressed_extents to be called and crash occurs because\nasync_chunk::inode suddenly became NULL. The call trace was similar to:\n\n    pc : submit_compressed_extents+0x38/0x3d0\n    lr : async_cow_submit+0x50/0xd0\n    sp : ffff800015d4bc20\n\n    <registers omitted for brevity>\n\n    Call trace:\n     submit_compressed_extents+0x38/0x3d0\n     async_cow_submit+0x50/0xd0\n     run_ordered_work+0xc8/0x280\n     btrfs_work_helper+0x98/0x250\n     process_one_work+0x1f0/0x4ac\n     worker_thread+0x188/0x504\n     kthread+0x110/0x114\n     ret_from_fork+0x10/0x18\n\nFix this by adding respective barrier calls which ensure that all\naccesses preceding setting of WORK_DONE_BIT are strictly ordered before\nsetting the flag. At the same time add a read barrier after reading of\nWORK_DONE_BIT in run_ordered_work which ensures all subsequent loads\nwould be strictly ordered after reading the bit. This in turn ensures\nare all accesses before WORK_DONE_BIT are going to be strictly ordered\nbefore any access that can occur in ordered_func."}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/btrfs/async-thread.c"],"versions":[{"version":"08a9ff3264181986d1d692a4e6fce3669700c9f8","lessThan":"bd660a20fea3ec60a49709ef5360f145ec0fe779","status":"affected","versionType":"git"},{"version":"08a9ff3264181986d1d692a4e6fce3669700c9f8","lessThan":"637d652d351fd4f263ef302dc52f3971d314e500","status":"affected","versionType":"git"},{"version":"08a9ff3264181986d1d692a4e6fce3669700c9f8","lessThan":"804a9d239ae9cbe88e861a7cd62319cc6ec7b136","status":"affected","versionType":"git"},{"version":"08a9ff3264181986d1d692a4e6fce3669700c9f8","lessThan":"ed058d735a70f4b063323f1a7bb33cda0f987513","status":"affected","versionType":"git"},{"version":"08a9ff3264181986d1d692a4e6fce3669700c9f8","lessThan":"670f6b3867c8f0f11e5097f353b164cecfec6179","status":"affected","versionType":"git"},{"version":"08a9ff3264181986d1d692a4e6fce3669700c9f8","lessThan":"6adbc07ebcaf8bead08b21687d49e0fc94400987","status":"affected","versionType":"git"},{"version":"08a9ff3264181986d1d692a4e6fce3669700c9f8","lessThan":"47e6f9f69153247109042010f3a77579e9dc61ff","status":"affected","versionType":"git"},{"version":"08a9ff3264181986d1d692a4e6fce3669700c9f8","lessThan":"45da9c1767ac31857df572f0a909fbe88fd5a7e9","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/btrfs/async-thread.c"],"versions":[{"version":"3.15","status":"affected"},{"version":"0","lessThan":"3.15","status":"unaffected","versionType":"semver"},{"version":"4.4.293","lessThanOrEqual":"4.4.*","status":"unaffected","versionType":"semver"},{"version":"4.9.291","lessThanOrEqual":"4.9.*","status":"unaffected","versionType":"semver"},{"version":"4.14.256","lessThanOrEqual":"4.14.*","status":"unaffected","versionType":"semver"},{"version":"4.19.218","lessThanOrEqual":"4.19.*","status":"unaffected","versionType":"semver"},{"version":"5.4.162","lessThanOrEqual":"5.4.*","status":"unaffected","versionType":"semver"},{"version":"5.10.82","lessThanOrEqual":"5.10.*","status":"unaffected","versionType":"semver"},{"version":"5.15.5","lessThanOrEqual":"5.15.*","status":"unaffected","versionType":"semver"},{"version":"5.16","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.15","versionEndExcluding":"4.4.293"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.15","versionEndExcluding":"4.9.291"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.15","versionEndExcluding":"4.14.256"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.15","versionEndExcluding":"4.19.218"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.15","versionEndExcluding":"5.4.162"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.15","versionEndExcluding":"5.10.82"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.15","versionEndExcluding":"5.15.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.15","versionEndExcluding":"5.16"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/bd660a20fea3ec60a49709ef5360f145ec0fe779"},{"url":"https://git.kernel.org/stable/c/637d652d351fd4f263ef302dc52f3971d314e500"},{"url":"https://git.kernel.org/stable/c/804a9d239ae9cbe88e861a7cd62319cc6ec7b136"},{"url":"https://git.kernel.org/stable/c/ed058d735a70f4b063323f1a7bb33cda0f987513"},{"url":"https://git.kernel.org/stable/c/670f6b3867c8f0f11e5097f353b164cecfec6179"},{"url":"https://git.kernel.org/stable/c/6adbc07ebcaf8bead08b21687d49e0fc94400987"},{"url":"https://git.kernel.org/stable/c/47e6f9f69153247109042010f3a77579e9dc61ff"},{"url":"https://git.kernel.org/stable/c/45da9c1767ac31857df572f0a909fbe88fd5a7e9"}],"title":"btrfs: fix memory ordering between normal and ordered work functions","x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"problemTypes":[{"descriptions":[{"type":"CWE","lang":"en","description":"CWE-noinfo Not enough information"}]}],"metrics":[{"cvssV3_1":{"scope":"UNCHANGED","version":"3.1","baseScore":6.3,"attackVector":"NETWORK","baseSeverity":"MEDIUM","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L","integrityImpact":"LOW","userInteraction":"NONE","attackComplexity":"LOW","availabilityImpact":"LOW","privilegesRequired":"LOW","confidentialityImpact":"LOW"}},{"other":{"type":"ssvc","content":{"timestamp":"2024-04-10T19:44:25.164224Z","id":"CVE-2021-47189","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2024-11-01T17:56:06.717Z"}},{"providerMetadata":{"orgId":"af854a3a-2127-422b-91ae-364da2661108","shortName":"CVE","dateUpdated":"2024-08-04T05:32:07.308Z"},"title":"CVE Program Container","references":[{"url":"https://git.kernel.org/stable/c/bd660a20fea3ec60a49709ef5360f145ec0fe779","tags":["x_transferred"]},{"url":"https://git.kernel.org/stable/c/637d652d351fd4f263ef302dc52f3971d314e500","tags":["x_transferred"]},{"url":"https://git.kernel.org/stable/c/804a9d239ae9cbe88e861a7cd62319cc6ec7b136","tags":["x_transferred"]},{"url":"https://git.kernel.org/stable/c/ed058d735a70f4b063323f1a7bb33cda0f987513","tags":["x_transferred"]},{"url":"https://git.kernel.org/stable/c/670f6b3867c8f0f11e5097f353b164cecfec6179","tags":["x_transferred"]},{"url":"https://git.kernel.org/stable/c/6adbc07ebcaf8bead08b21687d49e0fc94400987","tags":["x_transferred"]},{"url":"https://git.kernel.org/stable/c/47e6f9f69153247109042010f3a77579e9dc61ff","tags":["x_transferred"]},{"url":"https://git.kernel.org/stable/c/45da9c1767ac31857df572f0a909fbe88fd5a7e9","tags":["x_transferred"]}]}]}}