{"id":"CVE-2026-90108","published":"2026-09-17T17:17:02.730","lastModified":"2026-09-17T17:17:02.730","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.","cvssScore":null,"cvssSeverity":null,"cvssVector":null,"cwes":[],"vendors":[],"products":[],"references":[{"url":"https://git.kernel.org/stable/c/036322025d6e440cb75fc6fecbba9a16b271a2ae","tags":[]},{"url":"https://git.kernel.org/stable/c/056395acb7041b3a1f2baa08d89a1938a8b8776a","tags":[]},{"url":"https://git.kernel.org/stable/c/0fb9a513766071ea9d5f3bf988e39241b8e9ee3b","tags":[]},{"url":"https://git.kernel.org/stable/c/7dd55348c0d9399a9448847819e9f3904ae507ad","tags":[]},{"url":"https://git.kernel.org/stable/c/b08aacfb226a840628151643b6a34eecf545d311","tags":[]},{"url":"https://git.kernel.org/stable/c/e25a602c45c76a7130878db72bcf6f76df04bf85","tags":[]}],"exploitRefs":[],"hasPoc":false,"ai":null}