{"api_version":"1","generated_at":"2026-09-05T19:24:06+00:00","cve":"CVE-2026-80811","urls":{"html":"https://cve.report/CVE-2026-80811","api":"https://cve.report/api/cve/CVE-2026-80811.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-80811","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-80811"},"summary":{"title":"io_uring/cmd: fix iovec leak when the async cmd is not recycled","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nio_uring/cmd: fix iovec leak when the async cmd is not recycled\n\nAn io_async_cmd carries an iovec array in ->vec.iovec, allocated when the\nvec has to grow and kept across recycling through ctx->cmd_cache.  On two\npaths nothing frees it and io_clean_op()'s kfree(req->async_data) drops\nthe io_async_cmd without it.\n\nio_req_uring_cleanup() clears the async data flags only when\nio_alloc_cache_put() succeeds, and the cache holds IO_ALLOC_CACHE_MAX ==\n128 entries, so once it is full the put fails and the vec is left behind.\nAn NVMe passthrough workload gets there without doing anything unusual:\nnvme_uring_cmd_io() returns -EIOCBQUEUED, so the io_async_cmd stays\nattached for the lifetime of the command and the live object count tracks\nthe queue depth.  Above 128 the puts start failing.\n\n->cleanup is the last chance to free an inherited vec, since\nio_req_uring_cleanup() returns early for an io-wq issued command and is\nnot called at all for one completed without ever being issued.  But\nio_clean_op() calls ->cleanup only if REQ_F_NEED_CLEANUP is set, and for\nuring_cmd that happens only where the vec has to grow, so a command\nreusing a large enough cached vec never sets it.  io_rw_alloc_async() and\nio_msg_alloc_async() flag an inherited vec for exactly this reason;\nio_uring_cmd_prep() does not.\n\nFlag an inherited vec in io_uring_cmd_prep(), and free the vec when the\ncache put fails, as io_req_rw_cleanup() does.\n\nThe leak is invisible under KASAN, where io_alloc_cache_vec_kasan() frees\nthe vec unconditionally.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-09-04 16:18:08","updated_at":"2026-09-04 16:18:08"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/b290de4d16d75b6c1ef42025b47f5d94eb1ec09f","name":"https://git.kernel.org/stable/c/b290de4d16d75b6c1ef42025b47f5d94eb1ec09f","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/bb34ae5da3365699d53a756f4c96b6ea9f8ba0c1","name":"https://git.kernel.org/stable/c/bb34ae5da3365699d53a756f4c96b6ea9f8ba0c1","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/b6a768aa975b9ca81b92f028bdd975d1f8237894","name":"https://git.kernel.org/stable/c/b6a768aa975b9ca81b92f028bdd975d1f8237894","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/7068d3587a64a24943a7c9e232976da2c9e0e303","name":"https://git.kernel.org/stable/c/7068d3587a64a24943a7c9e232976da2c9e0e303","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-80811","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-80811","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 3a4689ac109f18f23ea0d0c1c79e055142796858 b6a768aa975b9ca81b92f028bdd975d1f8237894 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 3a4689ac109f18f23ea0d0c1c79e055142796858 b290de4d16d75b6c1ef42025b47f5d94eb1ec09f git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 3a4689ac109f18f23ea0d0c1c79e055142796858 7068d3587a64a24943a7c9e232976da2c9e0e303 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 3a4689ac109f18f23ea0d0c1c79e055142796858 bb34ae5da3365699d53a756f4c96b6ea9f8ba0c1 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.15","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.15 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.47 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.1.11 7.1.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2.1 7.2.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.3-rc1 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["io_uring/uring_cmd.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"b6a768aa975b9ca81b92f028bdd975d1f8237894","status":"affected","version":"3a4689ac109f18f23ea0d0c1c79e055142796858","versionType":"git"},{"lessThan":"b290de4d16d75b6c1ef42025b47f5d94eb1ec09f","status":"affected","version":"3a4689ac109f18f23ea0d0c1c79e055142796858","versionType":"git"},{"lessThan":"7068d3587a64a24943a7c9e232976da2c9e0e303","status":"affected","version":"3a4689ac109f18f23ea0d0c1c79e055142796858","versionType":"git"},{"lessThan":"bb34ae5da3365699d53a756f4c96b6ea9f8ba0c1","status":"affected","version":"3a4689ac109f18f23ea0d0c1c79e055142796858","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["io_uring/uring_cmd.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"6.15"},{"lessThan":"6.15","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.47","versionType":"semver"},{"lessThanOrEqual":"7.1.*","status":"unaffected","version":"7.1.11","versionType":"semver"},{"lessThanOrEqual":"7.2.*","status":"unaffected","version":"7.2.1","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.3-rc1","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.47","versionStartIncluding":"6.15","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.1.11","versionStartIncluding":"6.15","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2.1","versionStartIncluding":"6.15","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.3-rc1","versionStartIncluding":"6.15","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nio_uring/cmd: fix iovec leak when the async cmd is not recycled\n\nAn io_async_cmd carries an iovec array in ->vec.iovec, allocated when the\nvec has to grow and kept across recycling through ctx->cmd_cache.  On two\npaths nothing frees it and io_clean_op()'s kfree(req->async_data) drops\nthe io_async_cmd without it.\n\nio_req_uring_cleanup() clears the async data flags only when\nio_alloc_cache_put() succeeds, and the cache holds IO_ALLOC_CACHE_MAX ==\n128 entries, so once it is full the put fails and the vec is left behind.\nAn NVMe passthrough workload gets there without doing anything unusual:\nnvme_uring_cmd_io() returns -EIOCBQUEUED, so the io_async_cmd stays\nattached for the lifetime of the command and the live object count tracks\nthe queue depth.  Above 128 the puts start failing.\n\n->cleanup is the last chance to free an inherited vec, since\nio_req_uring_cleanup() returns early for an io-wq issued command and is\nnot called at all for one completed without ever being issued.  But\nio_clean_op() calls ->cleanup only if REQ_F_NEED_CLEANUP is set, and for\nuring_cmd that happens only where the vec has to grow, so a command\nreusing a large enough cached vec never sets it.  io_rw_alloc_async() and\nio_msg_alloc_async() flag an inherited vec for exactly this reason;\nio_uring_cmd_prep() does not.\n\nFlag an inherited vec in io_uring_cmd_prep(), and free the vec when the\ncache put fails, as io_req_rw_cleanup() does.\n\nThe leak is invisible under KASAN, where io_alloc_cache_vec_kasan() frees\nthe vec unconditionally."}],"providerMetadata":{"dateUpdated":"2026-09-04T15:13:31.761Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/b6a768aa975b9ca81b92f028bdd975d1f8237894"},{"url":"https://git.kernel.org/stable/c/b290de4d16d75b6c1ef42025b47f5d94eb1ec09f"},{"url":"https://git.kernel.org/stable/c/7068d3587a64a24943a7c9e232976da2c9e0e303"},{"url":"https://git.kernel.org/stable/c/bb34ae5da3365699d53a756f4c96b6ea9f8ba0c1"}],"title":"io_uring/cmd: fix iovec leak when the async cmd is not recycled","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-80811","datePublished":"2026-09-04T15:13:31.761Z","dateReserved":"2026-08-26T14:34:25.794Z","dateUpdated":"2026-09-04T15:13:31.761Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-09-04 16:18:08","lastModifiedDate":"2026-09-04 16:18:08","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"80811","Ordinal":"1","Title":"io_uring/cmd: fix iovec leak when the async cmd is not recycled","CVE":"CVE-2026-80811","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"80811","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nio_uring/cmd: fix iovec leak when the async cmd is not recycled\n\nAn io_async_cmd carries an iovec array in ->vec.iovec, allocated when the\nvec has to grow and kept across recycling through ctx->cmd_cache.  On two\npaths nothing frees it and io_clean_op()'s kfree(req->async_data) drops\nthe io_async_cmd without it.\n\nio_req_uring_cleanup() clears the async data flags only when\nio_alloc_cache_put() succeeds, and the cache holds IO_ALLOC_CACHE_MAX ==\n128 entries, so once it is full the put fails and the vec is left behind.\nAn NVMe passthrough workload gets there without doing anything unusual:\nnvme_uring_cmd_io() returns -EIOCBQUEUED, so the io_async_cmd stays\nattached for the lifetime of the command and the live object count tracks\nthe queue depth.  Above 128 the puts start failing.\n\n->cleanup is the last chance to free an inherited vec, since\nio_req_uring_cleanup() returns early for an io-wq issued command and is\nnot called at all for one completed without ever being issued.  But\nio_clean_op() calls ->cleanup only if REQ_F_NEED_CLEANUP is set, and for\nuring_cmd that happens only where the vec has to grow, so a command\nreusing a large enough cached vec never sets it.  io_rw_alloc_async() and\nio_msg_alloc_async() flag an inherited vec for exactly this reason;\nio_uring_cmd_prep() does not.\n\nFlag an inherited vec in io_uring_cmd_prep(), and free the vec when the\ncache put fails, as io_req_rw_cleanup() does.\n\nThe leak is invisible under KASAN, where io_alloc_cache_vec_kasan() frees\nthe vec unconditionally.","Type":"Description","Title":"io_uring/cmd: fix iovec leak when the async cmd is not recycled"}]}}}