CVE-2026-98821

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.