From 2a42e6fe1293f2e2d579c9fe5bbab056dd8b880e Mon Sep 17 00:00:00 2001 From: Yang Xiuwei Date: Wed, 23 Sep 2026 17:37:32 +0800 Subject: [PATCH] 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. Fixes: 2729a60bbfb9 ("block: don't silently ignore metadata for sync read/write") Assisted-by: LLM Signed-off-by: Yang Xiuwei Link: https://patch.msgid.link/20260923093732.1504291-1-yangxiuwei@kylinos.cn Signed-off-by: Jens Axboe --- block/fops.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/block/fops.c b/block/fops.c index 2ce7c6c4714e..c915ec0126d7 100644 --- a/block/fops.c +++ b/block/fops.c @@ -402,6 +402,11 @@ static ssize_t blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter) if (blkdev_dio_invalid(bdev, iocb, iter)) return -EINVAL; + /* HIPRI needs private as bio; HAS_METADATA keeps it as uio_meta */ + if ((iocb->ki_flags & IOCB_HIPRI) && + (iocb->ki_flags & IOCB_HAS_METADATA)) + return -EOPNOTSUPP; + if (iov_iter_rw(iter) == WRITE) { u16 max_write_streams = bdev_max_write_streams(bdev);