CVE-2026-46089
MediumCVSS 5.5Exploitation Probability (EPSS)
Low risk2th percentile - higher than 2% of all known CVEs
Summary
In the Linux kernel, a vulnerability in the zram driver causes partial discard operations to hang indefinitely. The issue is due to missing bio_endio() call after immediate request completion, leading to blkdiscard process freeze.
Risk Assessment
An attacker or user can cause a permanent system hang by executing blkdiscard with a page size smaller than the zram block size, resulting in denial of service (DoS).
Recommendation
Apply the Linux kernel patch that adds bio_endio() call for partial discard requests in the zram driver immediately.
Original NVD description (English source)
In the Linux kernel, the following vulnerability has been resolved: zram: do not forget to endio for partial discard requests As reported by Qu Wenruo and Avinesh Kumar, the following getconf PAGESIZE 65536 blkdiscard -p 4k /dev/zram0 takes literally forever to complete. zram doesn't support partial discards and just returns immediately w/o doing any discard work in such cases. The problem is that we forget to endio on our way out, so blkdiscard sleeps forever in submit_bio_wait(). Fix this by jumping to end_bio label, which does bio_endio().