CVE-2026-98821

medium

Description

In the Linux kernel, the following vulnerability has been resolved: block: reject polled dio with user integrity metadata IOCB_HAS_METADATA leaves iocb->private as a uio_meta, while iocb_bio_iopoll() expects a bio. Since 2729a60bbfb9, metadata I/O always uses __blkdev_direct_IO(), which never publishes the bio for polling, so IOPOLL calls bio_poll() on the uio_meta. Reproducer: io_uring IOPOLL plus a PI attribute on an integrity device (scsi_debug dif=1 dix=1). KASAN reports: Oops: general protection fault, probably for non-canonical address 0xdffffc0000000004 KASAN: null-ptr-deref in range [0x0000000000000020-0x0000000000000027] RIP: 0010:bio_poll+0x9d/0x4b0 Call Trace: iocb_bio_iopoll+0x5b/0x80 io_uring_classic_poll+0xf3/0x140 io_do_iopoll+0x4e3/0xc00 io_iopoll_check+0x275/0x560 __do_sys_io_uring_enter+0x2e5/0x720 Return -EOPNOTSUPP when HIPRI is combined with user metadata.

References

https://git.kernel.org/stable/c/dd33c03cefccdfcb223e9e6262643d64f8c1ae20

https://git.kernel.org/stable/c/c97ef13ad96be0e08af38dfa2ed40cded0b53e1b

https://git.kernel.org/stable/c/2a42e6fe1293f2e2d579c9fe5bbab056dd8b880e

https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-103906

Details

Source: Mitre, NVD

Published: 2026-10-18

Updated: 2026-10-18

Risk Information

CVSS v2

Base Score: 2.1

Vector: CVSS2#AV:L/AC:L/Au:N/C:N/I:P/A:N

Severity: Low

CVSS v3

Base Score: 5.5

Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N

Severity: Medium