Merge tag 'block-6.18-20251023' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux

Pull block fixes from Jens Axboe:

 - Fix dma alignment for PI

 - Fix selinux bogosity with nbd, where sendmsg would get rejected

* tag 'block-6.18-20251023' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux:
  block: require LBA dma_alignment when using PI
  nbd: override creds to kernel when calling sock_{send,recv}msg()

Author: torvalds

block/blk-settings.c

@@ -184,6 +184,16 @@ static int blk_validate_integrity_limits(struct queue_limits *lim)
 	if (!bi->interval_exp)
 		bi->interval_exp = ilog2(lim->logical_block_size);
 
+	/*
+	 * The PI generation / validation helpers do not expect intervals to
+	 * straddle multiple bio_vecs.  Enforce alignment so that those are
+	 * never generated, and that each buffer is aligned as expected.
+	 */
+	if (bi->csum_type) {
+		lim->dma_alignment = max(lim->dma_alignment,
+					(1U << bi->interval_exp) - 1);
+	}
+
 	return 0;
 }
 

drivers/block/nbd.c

@@ -52,6 +52,7 @@
 static DEFINE_IDR(nbd_index_idr);
 static DEFINE_MUTEX(nbd_index_mutex);
 static struct workqueue_struct *nbd_del_wq;
+static struct cred *nbd_cred;
 static int nbd_total_devices = 0;
 
 struct nbd_sock {
@@ -554,6 +555,7 @@ static int __sock_xmit(struct nbd_device *nbd, struct socket *sock, int send,
 	int result;
 	struct msghdr msg = {} ;
 	unsigned int noreclaim_flag;
+	const struct cred *old_cred;
 
 	if (unlikely(!sock)) {
 		dev_err_ratelimited(disk_to_dev(nbd->disk),
@@ -562,6 +564,8 @@ static int __sock_xmit(struct nbd_device *nbd, struct socket *sock, int send,
 		return -EINVAL;
 	}
 
+	old_cred = override_creds(nbd_cred);
+
 	msg.msg_iter = *iter;
 
 	noreclaim_flag = memalloc_noreclaim_save();
@@ -586,6 +590,8 @@ static int __sock_xmit(struct nbd_device *nbd, struct socket *sock, int send,
 
 	memalloc_noreclaim_restore(noreclaim_flag);
 
+	revert_creds(old_cred);
+
 	return result;
 }
 
@@ -2677,7 +2683,15 @@ static int __init nbd_init(void)
 		return -ENOMEM;
 	}
 
+	nbd_cred = prepare_kernel_cred(&init_task);
+	if (!nbd_cred) {
+		destroy_workqueue(nbd_del_wq);
+		unregister_blkdev(NBD_MAJOR, "nbd");
+		return -ENOMEM;
+	}
+
 	if (genl_register_family(&nbd_genl_family)) {
+		put_cred(nbd_cred);
 		destroy_workqueue(nbd_del_wq);
 		unregister_blkdev(NBD_MAJOR, "nbd");
 		return -EINVAL;
@@ -2732,6 +2746,7 @@ static void __exit nbd_cleanup(void)
 	/* Also wait for nbd_dev_remove_work() completes */
 	destroy_workqueue(nbd_del_wq);
 
+	put_cred(nbd_cred);
 	idr_destroy(&nbd_index_idr);
 	unregister_blkdev(NBD_MAJOR, "nbd");
 }