CVE-2026-23253
In the Linux kernel, the following vulnerability has been resolved: media: dvb-core: fix wrong reinitialization of ringbuffer on reopen dvb_dvr_open() calls dvb_ringbuffer_init() when a new reader opens the DVR device. dvb_ringbuffer_init() calls init_waitqueue_head(), which reinitializes the waitqueue list head to empty. Since dmxdev->dvr_buffer.queue is a shared waitqueue (all opens of the same DVR device share it), this orphans any existing waitqueue entries from io_uring poll or epoll, leaving them with stale prev/next pointers while the list head is reset to {self, self}. The waitqueue and spinlock in dvr_buffer are already properly initialized once in dvb_dmxdev_init(). The open path only needs to reset the buffer data pointer, size, and read/write positions. Replace the dvb_ringbuffer_init() call in dvb_dvr_open() with direct assignment of data/size and a call to dvb_ringbuffer_reset(), which properly resets pread, pwrite, and error with correct memory ordering without touching the waitqueue or spinlock.
- CVSS 3.1
- 7.8
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - EPSS
- 0.1% chance of exploitation in the next 30 days; higher than 3% of CVEs (scores of 2026-10-25)
- CWE
- CWE-665
- Published
- Modified
- Record from
- the NVD, synced
Affected
- linux:linux_kernel
References
- https://git.kernel.org/stable/c/32eb8e4adc207ef31bc6e5ae56bab940b0176066
- https://git.kernel.org/stable/c/527cfa8a3486b3555c5c15e2f62be484a11398dc
- https://git.kernel.org/stable/c/af050ab44fa1b1897a940d7d756e512232f5e5df
- https://git.kernel.org/stable/c/bfbc0b5b32a8f28ce284add619bf226716a59bc0
- https://git.kernel.org/stable/c/cfd94642025e6f71c8f754bdec0800ee95e4f3dd