{"id":"AZL-102839","summary":"CVE-2026-90081 affecting package kernel 6.6.150.1-1","details":"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-\u003em_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.","modified":"2026-09-19T05:33:49Z","published":"2026-09-17T17:16:57Z","upstream":["CVE-2026-90081"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-90081"}],"affected":[{"package":{"name":"kernel","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/kernel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"6.6.150.1-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-102839.json"}}],"schema_version":"1.9.0"}