{"cve":"CVE-2026-90081","nvd":{"published":"2026-09-17T17:16:57.423","modified":"2026-10-19T09:18:56.993","status":"Received","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/rds: use wq_has_sleeper() in rds_cong_map_updated()\n\nrds_cong_map_updated() runs after a peer's congestion map has been\nrewritten (by rds_tcp_cong_recv() and rds_ib_cong_recv(), or the\nclear-all in the loopback and IB send-completion paths).  It bumps\nrds_cong_generation and then checks waitqueue_active() on\nmap->m_waitq and on rds_poll_waitq to decide whether anyone needs\nwaking.  atomic_inc() carries no ordering and waitqueue_active() is a\nplain load, so nothing orders the map and generation stores before\nthe wait queue reads.  The waiters do the mirror image: rds_cong_wait()\nadds itself to m_waitq and then tests the port bit, and rds_poll()\nregisters on rds_poll_waitq and then reads the generation.  That is\nthe store-buffering pattern described above waitqueue_active() in\ninclude/linux/wait.h - the updater can observe an empty wait queue\nwhile the waiter still observes the port as congested, and no wake-up\nis issued.\n\nrds_cong_wait() is an interruptible sleep with no timeout, so a\nsender blocked on a congested port stays blocked until the next\ncongestion update from that peer arrives or a signal is delivered.\nA poll() waiter misses the map-updated notification the same way.\n\nUse wq_has_sleeper(), which is waitqueue_active() preceded by the\nrequired full barrier, as rds_tcp_state_change() already does for\nthe same pattern.","cvss_v4":null,"cvss_v3":null,"cwes":[],"references":["https://git.kernel.org/stable/c/0e169f6a2adeb17b5577ed7e8abd642465bb50ec","https://git.kernel.org/stable/c/281f9fda2e06d6c211bb365a5379ed2e05cc2e21","https://git.kernel.org/stable/c/2a809d7896dbf18e1ecfbdd930f71c9fc298b16d","https://git.kernel.org/stable/c/42884bd8b8fd023d6a610a695bd5ddd1d5dece17","https://git.kernel.org/stable/c/a526214b9f0548ca0e53a6e0d1727d8ea9befc23"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:55:23.253742848+00:00"},"epss":{"cve":"CVE-2026-90081","score":0.00216,"percentile":0.1197,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}