{"id":"CVE-2026-90108","state":"PUBLISHED","title":"net/smc: free stashed qentry before overwrite in REQ_ADD_LINK to ADD_LINK transition","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/smc: free stashed qentry before overwrite in REQ_ADD_LINK to ADD_LINK transition\n\nWhen smc_llc_event_handler() transitions the local LLC flow from\nSMC_LLC_FLOW_REQ_ADD_LINK to SMC_LLC_FLOW_ADD_LINK on arrival of an ADD_LINK\nrequest, it calls smc_llc_flow_qentry_set() unconditionally:\n\n\tif (lgr->llc_flow_lcl.type == SMC_LLC_FLOW_REQ_ADD_LINK) {\n\t\tlgr->llc_flow_lcl.type = SMC_LLC_FLOW_ADD_LINK;\n\t\tsmc_llc_flow_qentry_set(&lgr->llc_flow_lcl, qentry);\n\t\t...\n\t}\n\nA CONFIRM_LINK or ADD_LINK_CONT arriving while flow->type is\nSMC_LLC_FLOW_REQ_ADD_LINK is stashed into flow->qentry via the\nSMC_LLC_CONFIRM_LINK / SMC_LLC_ADD_LINK_CONT handler (which stores into\nflow->qentry for any non-NONE flow type).  When the subsequent ADD_LINK\narrives, the REQ_ADD_LINK branch overwrites flow->qentry with the new pointer\nwithout first freeing the stashed allocation, leaking one kmalloc object.\n\nThe stashed entry has no consumer: smc_llc_wait() is only called from\nllc_add_link_work, which is not yet scheduled while the flow type remains\nREQ_ADD_LINK.  No waiter is sleeping on llc_msg_waiter at this point.\nIt is safe to unconditionally free any stashed qentry before\nthe overwrite.\n\nCall smc_llc_flow_qentry_del() before smc_llc_flow_qentry_set() in the\nREQ_ADD_LINK branch.  smc_llc_flow_qentry_del() already checks flow->qentry\nbefore freeing, so the normal path where no entry is stashed is a no-op.","publishedAt":"2026-09-17T16:06:16.813Z","updatedAt":"2026-10-19T08:58:06.785Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"b4ba4652b3f8b7c9bbb5786f8acf4724bdab2196","status":"affected","lessThan":"7dd55348c0d9399a9448847819e9f3904ae507ad","versionType":"git"},{"version":"b4ba4652b3f8b7c9bbb5786f8acf4724bdab2196","status":"affected","lessThan":"056395acb7041b3a1f2baa08d89a1938a8b8776a","versionType":"git"},{"version":"b4ba4652b3f8b7c9bbb5786f8acf4724bdab2196","status":"affected","lessThan":"b08aacfb226a840628151643b6a34eecf545d311","versionType":"git"},{"version":"b4ba4652b3f8b7c9bbb5786f8acf4724bdab2196","status":"affected","lessThan":"0fb9a513766071ea9d5f3bf988e39241b8e9ee3b","versionType":"git"},{"version":"b4ba4652b3f8b7c9bbb5786f8acf4724bdab2196","status":"affected","lessThan":"e25a602c45c76a7130878db72bcf6f76df04bf85","versionType":"git"},{"version":"b4ba4652b3f8b7c9bbb5786f8acf4724bdab2196","status":"affected","lessThan":"036322025d6e440cb75fc6fecbba9a16b271a2ae","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/smc/smc_llc.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.16","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.16","versionType":"semver"},{"version":"6.1.188","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.157","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.110","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.52","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.6","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/smc/smc_llc.c"]}],"references":["https://git.kernel.org/stable/c/7dd55348c0d9399a9448847819e9f3904ae507ad","https://git.kernel.org/stable/c/056395acb7041b3a1f2baa08d89a1938a8b8776a","https://git.kernel.org/stable/c/b08aacfb226a840628151643b6a34eecf545d311","https://git.kernel.org/stable/c/0fb9a513766071ea9d5f3bf988e39241b8e9ee3b","https://git.kernel.org/stable/c/e25a602c45c76a7130878db72bcf6f76df04bf85","https://git.kernel.org/stable/c/036322025d6e440cb75fc6fecbba9a16b271a2ae"],"weaknesses":[],"ingestedAt":"2026-10-29T20:13:34.582Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/90xxx/CVE-2026-90108.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-90108","state":"PUBLISHED","datePublished":"2026-09-17T16:06:16.813Z","dateUpdated":"2026-10-19T08:58:06.785Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-09-11T19:38:34.787Z"},"containers":{"cna":{"title":"net/smc: free stashed qentry before overwrite in REQ_ADD_LINK to ADD_LINK transition","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/smc: free stashed qentry before overwrite in REQ_ADD_LINK to ADD_LINK transition\n\nWhen smc_llc_event_handler() transitions the local LLC flow from\nSMC_LLC_FLOW_REQ_ADD_LINK to SMC_LLC_FLOW_ADD_LINK on arrival of an ADD_LINK\nrequest, it calls smc_llc_flow_qentry_set() unconditionally:\n\n\tif (lgr->llc_flow_lcl.type == SMC_LLC_FLOW_REQ_ADD_LINK) {\n\t\tlgr->llc_flow_lcl.type = SMC_LLC_FLOW_ADD_LINK;\n\t\tsmc_llc_flow_qentry_set(&lgr->llc_flow_lcl, qentry);\n\t\t...\n\t}\n\nA CONFIRM_LINK or ADD_LINK_CONT arriving while flow->type is\nSMC_LLC_FLOW_REQ_ADD_LINK is stashed into flow->qentry via the\nSMC_LLC_CONFIRM_LINK / SMC_LLC_ADD_LINK_CONT handler (which stores into\nflow->qentry for any non-NONE flow type).  When the subsequent ADD_LINK\narrives, the REQ_ADD_LINK branch overwrites flow->qentry with the new pointer\nwithout first freeing the stashed allocation, leaking one kmalloc object.\n\nThe stashed entry has no consumer: smc_llc_wait() is only called from\nllc_add_link_work, which is not yet scheduled while the flow type remains\nREQ_ADD_LINK.  No waiter is sleeping on llc_msg_waiter at this point.\nIt is safe to unconditionally free any stashed qentry before\nthe overwrite.\n\nCall smc_llc_flow_qentry_del() before smc_llc_flow_qentry_set() in the\nREQ_ADD_LINK branch.  smc_llc_flow_qentry_del() already checks flow->qentry\nbefore freeing, so the normal path where no entry is stashed is a no-op."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"b4ba4652b3f8b7c9bbb5786f8acf4724bdab2196","status":"affected","lessThan":"7dd55348c0d9399a9448847819e9f3904ae507ad","versionType":"git"},{"version":"b4ba4652b3f8b7c9bbb5786f8acf4724bdab2196","status":"affected","lessThan":"056395acb7041b3a1f2baa08d89a1938a8b8776a","versionType":"git"},{"version":"b4ba4652b3f8b7c9bbb5786f8acf4724bdab2196","status":"affected","lessThan":"b08aacfb226a840628151643b6a34eecf545d311","versionType":"git"},{"version":"b4ba4652b3f8b7c9bbb5786f8acf4724bdab2196","status":"affected","lessThan":"0fb9a513766071ea9d5f3bf988e39241b8e9ee3b","versionType":"git"},{"version":"b4ba4652b3f8b7c9bbb5786f8acf4724bdab2196","status":"affected","lessThan":"e25a602c45c76a7130878db72bcf6f76df04bf85","versionType":"git"},{"version":"b4ba4652b3f8b7c9bbb5786f8acf4724bdab2196","status":"affected","lessThan":"036322025d6e440cb75fc6fecbba9a16b271a2ae","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/smc/smc_llc.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.16","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.16","versionType":"semver"},{"version":"6.1.188","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.157","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.110","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.52","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.6","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/smc/smc_llc.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/7dd55348c0d9399a9448847819e9f3904ae507ad"},{"url":"https://git.kernel.org/stable/c/056395acb7041b3a1f2baa08d89a1938a8b8776a"},{"url":"https://git.kernel.org/stable/c/b08aacfb226a840628151643b6a34eecf545d311"},{"url":"https://git.kernel.org/stable/c/0fb9a513766071ea9d5f3bf988e39241b8e9ee3b"},{"url":"https://git.kernel.org/stable/c/e25a602c45c76a7130878db72bcf6f76df04bf85"},{"url":"https://git.kernel.org/stable/c/036322025d6e440cb75fc6fecbba9a16b271a2ae"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-19T08:58:06.785Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.16","versionEndExcluding":"6.1.188"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.16","versionEndExcluding":"6.6.157"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.16","versionEndExcluding":"6.12.110"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.16","versionEndExcluding":"6.18.52"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.16","versionEndExcluding":"7.2.6"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.16","versionEndExcluding":"7.3"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}