{"id":"CVE-2026-80859","summary":"fuse: fix missing barrier when checking io-uring readiness","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nfuse: fix missing barrier when checking io-uring readiness\n\nfuse_block_alloc() reads fch-\u003einitialized and then fch-\u003eio_uring.\nfch-\u003eio_uring is set before fch-\u003einitialized, ordered by the smp_wmb()\nin fuse_chan_set_intialized(), but fuse_block_alloc() has no matching\nread barrier between the two loads.\n\nThis may lead a CPU to observe fch-\u003einitialized=1 but fch-\u003eio_uring=0,\nand skip the check that blocks request allocation until the io-uring\nqueues are ready. This can reintroduce the lock-order inversion deadlock\nthat commit 3393ff964e0f prevents.\n\nAdd an smp_rmb() barrier to pair with the smp_wmb() in\nfuse_chan_set_initialized() to prevent this.","modified":"2026-09-06T03:46:59.616773315Z","published":"2026-09-04T15:55:13.378Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/80xxx/CVE-2026-80859.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/dd9c835709f4bb3e4256eea7573e4e6e18f956de"},{"type":"WEB","url":"https://git.kernel.org/stable/c/edb310bc27f0ad83e7fd558a3caf1a94ca511654"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/80xxx/CVE-2026-80859.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-80859"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"3393ff964e0fa5def66570c54a4612bf9df06b76"},{"fixed":"dd9c835709f4bb3e4256eea7573e4e6e18f956de"},{"fixed":"edb310bc27f0ad83e7fd558a3caf1a94ca511654"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-80859.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"6.14.0"},{"fixed":"7.2.3"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-80859.json"}}],"schema_version":"1.9.0"}