{"id":"CVE-2026-23253","summary":"media: dvb-core: fix wrong reinitialization of ringbuffer on reopen","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nmedia: dvb-core: fix wrong reinitialization of ringbuffer on reopen\n\ndvb_dvr_open() calls dvb_ringbuffer_init() when a new reader opens the\nDVR device.  dvb_ringbuffer_init() calls init_waitqueue_head(), which\nreinitializes the waitqueue list head to empty.\n\nSince dmxdev-\u003edvr_buffer.queue is a shared waitqueue (all opens of the\nsame DVR device share it), this orphans any existing waitqueue entries\nfrom io_uring poll or epoll, leaving them with stale prev/next pointers\nwhile the list head is reset to {self, self}.\n\nThe waitqueue and spinlock in dvr_buffer are already properly\ninitialized once in dvb_dmxdev_init().  The open path only needs to\nreset the buffer data pointer, size, and read/write positions.\n\nReplace the dvb_ringbuffer_init() call in dvb_dvr_open() with direct\nassignment of data/size and a call to dvb_ringbuffer_reset(), which\nproperly resets pread, pwrite, and error with correct memory ordering\nwithout touching the waitqueue or spinlock.","modified":"2026-04-14T03:48:19.926934Z","published":"2026-03-18T17:01:44.126Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/23xxx/CVE-2026-23253.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/32eb8e4adc207ef31bc6e5ae56bab940b0176066"},{"type":"WEB","url":"https://git.kernel.org/stable/c/af050ab44fa1b1897a940d7d756e512232f5e5df"},{"type":"WEB","url":"https://git.kernel.org/stable/c/bfbc0b5b32a8f28ce284add619bf226716a59bc0"},{"type":"WEB","url":"https://git.kernel.org/stable/c/cfd94642025e6f71c8f754bdec0800ee95e4f3dd"},{"type":"WEB","url":"https://git.kernel.org/stable/c/d71781bad59b1c9d60d7068004581f9bf19c0c9d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/f1e520ca2e83ece6731af6167c9e5e16931ecba0"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/23xxx/CVE-2026-23253.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-23253"},{"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":"34731df288a5ffe4b0c396caf8cd24c6a710a222"},{"fixed":"f1e520ca2e83ece6731af6167c9e5e16931ecba0"},{"fixed":"af050ab44fa1b1897a940d7d756e512232f5e5df"},{"fixed":"d71781bad59b1c9d60d7068004581f9bf19c0c9d"},{"fixed":"cfd94642025e6f71c8f754bdec0800ee95e4f3dd"},{"fixed":"32eb8e4adc207ef31bc6e5ae56bab940b0176066"},{"fixed":"bfbc0b5b32a8f28ce284add619bf226716a59bc0"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-23253.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"2.6.17"},{"fixed":"6.1.167"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.130"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.77"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.17"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"6.19.7"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-23253.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"}]}