{"id":"CVE-2026-89748","summary":"tracing: Fix retry exhaustion in simple ring buffer reader swap","details":"In the Linux kernel, the following vulnerability has been resolved:\n\ntracing: Fix retry exhaustion in simple ring buffer reader swap\n\nsimple_ring_buffer_swap_reader_page() starts with retry set to 8 and\npost-decrements it only after a failed link replacement. On the final\nattempt, a successful replacement leaves retry at zero, while a failed\nreplacement leaves it at -1.\n\nThe current !retry test reverses both outcomes. It returns an error after\na successful final replacement, leaving the link update complete but the\nreader bookkeeping unfinished. After a failed final replacement, it\nfalls through and updates the head and reader pointers as though the\nreplacement succeeded, which can corrupt the ring.\n\nTreat only a negative counter as exhaustion and return the documented\n-EBUSY error.","modified":"2026-09-13T03:47:20.526376710Z","published":"2026-09-11T19:46:53.070Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89748.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/df02489aa3aa1834659f0d20c89f7d212047d268"},{"type":"WEB","url":"https://git.kernel.org/stable/c/e0d3aed7b12cf37b74c7cc5265073d0263b49cde"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89748.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89748"},{"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":"34e5b958bdad0f9cf16306368bbc2dc5b2a50143"},{"fixed":"df02489aa3aa1834659f0d20c89f7d212047d268"},{"fixed":"e0d3aed7b12cf37b74c7cc5265073d0263b49cde"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-89748.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"7.1.0"},{"fixed":"7.2.4"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-89748.json"}}],"schema_version":"1.9.0"}