Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Fix error output of boot instance creation failure

   Currently if a boot instance creation fails, instead of printing out
   the name of the instance that failed, it prints "(null)". That is
   because it prints "cur_str" that had already been processed by
   strsep(). Print the saved name instead.

   While at it, print the error code of the failure.

 - Fix use-after-free for same named historgrams

   Histograms can be named so that they can be used in multiple events.
   But if the named histogram has a variable attached, the second event
   that uses the named histogram which duplicates it and needs to free
   the original after duplication leaves the old variable in place and
   still visible. If another histogram uses than variable, it will use
   the stale one which will try to reference the freed duplicate
   histogram and crash the kernel.

   Free the duplicate variables along with the duplicated histogram
   data.

 - Check return value of kthread_run() in event self test

   The events self tests uses a kthread for testing but does not check
   if it succeeded in creating a kthread. If the kthread creation were
   to fail, the code will still try to call kthread_stop() on the error
   returned.

 - Fix race between reading trace_pipe and updating subbuffer size

   If a user is reading the trace_pipe file at the same time they update
   the ring buffer sub-buffer size, can cause the trace_pipe read to
   read stale data. Add trace_access_lock() around updating the ring
   buffer sub-buffer size.

 - Fix eventfs_inode on failure path in creation of the events directory

   In the creation of the "events" directory, if after allocating the
   eventfs_inode a failure is detected, it calls cleanup_ei() which
   calls free_ei(). The free_ei() will test if eventfs_inode being freed
   has no children. It is a bug if it does. But on the failure case of
   the creation of the "events" directory, the children lists have not
   yet been initialized and the free will trigger a warning because
   list_empty() on an uninitialized list returns false.

   Move the initialization into init_ei() where it makes more sense and
   makes sure that a created eventfs_inode has its lists initialized
   upon creation.

 - Check return value of kthread_run() in ftrace direct sample code

   The sample code that shows how to use the ftrace direct calls does
   not test the return of kthread_run() to see if it succeeds. Return a
   failure if the kthread_run() doesn't succeed.

 - Clear user events state on fork in case of alloc failure

   On fork, the child gets a pointer to the parent's user events state.
   It makes a copy of it then updates the child's pointer to it. But if
   the allocation fails, the duplication function leaves the child with
   a pointer to its parent's descriptor. When the child cleans up its
   data, it will free the parent's descriptor while the parent is still
   using it.

   In the duplication function, set the child's user_event_mm to NULL
   before testing if the allocation succeeded, and when it exits it will
   not free the parent's descriptor.

 - Fix retry exhaustion in simple ring buffer reader swap

   simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
   post-decrements it only after a failed link replacement. On the final
   attempt, a successful replacement leaves retry at zero, while a
   failed replacement leaves it at -1.

   But the check for success expects the retry value to be non-zero and
   exits with an error on zero. This is the opposite result. Fix it.

 - Fail nicely when the remote swap_reader_page() returns an error

   Currently, if the swap_reader_page() of a remote buffer fails, it
   triggers a WARN_ON_ONCE() and continues normally. Instead, have it
   exit with an error and a pr_warn() print instead of a full WARNING.

* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Stop remote reader update when page swap fails
  tracing: Fix retry exhaustion in simple ring buffer reader swap
  tracing/user_events: Clear copied tracing state before fork duplication
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
  eventfs: Initialize ei->children and ei->list in init_ei()
  tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
  tracing: Fix crash passing ERR_PTR to kthread_stop()
  tracing: Fix use-after-free with same-name named triggers
  tracing: Fix logged instance name on creation failure

1 files changed, 598 insertions, 0 deletions

diff --git a/block/blk-crypto.c b/block/blk-crypto.c
new file mode 100644
index 000000000..bc3a9f595
--- /dev/null
+++ b/block/blk-crypto.c
@@ -0,0 +1,598 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2019 Google LLC
+ */
+
+/*
+ * Refer to Documentation/block/inline-encryption.rst for detailed explanation.
+ */
+
+#define pr_fmt(fmt) "blk-crypto: " fmt
+
+#include <linux/bio.h>
+#include <linux/blkdev.h>
+#include <linux/blk-crypto-profile.h>
+#include <linux/module.h>
+#include <linux/ratelimit.h>
+#include <linux/slab.h>
+
+#include "blk-crypto-internal.h"
+
+const struct blk_crypto_mode blk_crypto_modes[] = {
+	[BLK_ENCRYPTION_MODE_AES_256_XTS] = {
+		.name = "AES-256-XTS",
+		.cipher_str = "xts(aes)",
+		.keysize = 64,
+		.security_strength = 32,
+		.ivsize = 16,
+	},
+	[BLK_ENCRYPTION_MODE_AES_128_CBC_ESSIV] = {
+		.name = "AES-128-CBC-ESSIV",
+		.cipher_str = "essiv(cbc(aes),sha256)",
+		.keysize = 16,
+		.security_strength = 16,
+		.ivsize = 16,
+	},
+	[BLK_ENCRYPTION_MODE_ADIANTUM] = {
+		.name = "Adiantum",
+		.cipher_str = "adiantum(xchacha12,aes)",
+		.keysize = 32,
+		.security_strength = 32,
+		.ivsize = 32,
+	},
+	[BLK_ENCRYPTION_MODE_SM4_XTS] = {
+		.name = "SM4-XTS",
+		.cipher_str = "xts(sm4)",
+		.keysize = 32,
+		.security_strength = 16,
+		.ivsize = 16,
+	},
+};
+
+/*
+ * This number needs to be at least (the number of threads doing IO
+ * concurrently) * (maximum recursive depth of a bio), so that we don't
+ * deadlock on crypt_ctx allocations. The default is chosen to be the same
+ * as the default number of post read contexts in both EXT4 and F2FS.
+ */
+static int num_prealloc_crypt_ctxs = 128;
+
+module_param(num_prealloc_crypt_ctxs, int, 0444);
+MODULE_PARM_DESC(num_prealloc_crypt_ctxs,
+		"Number of bio crypto contexts to preallocate");
+
+static struct kmem_cache *bio_crypt_ctx_cache;
+static mempool_t *bio_crypt_ctx_pool;
+
+static int __init bio_crypt_ctx_init(void)
+{
+	size_t i;
+
+	bio_crypt_ctx_cache = KMEM_CACHE(bio_crypt_ctx, 0);
+	if (!bio_crypt_ctx_cache)
+		goto out_no_mem;
+
+	bio_crypt_ctx_pool = mempool_create_slab_pool(num_prealloc_crypt_ctxs,
+						      bio_crypt_ctx_cache);
+	if (!bio_crypt_ctx_pool)
+		goto out_no_mem;
+
+	/* This is assumed in various places. */
+	BUILD_BUG_ON(BLK_ENCRYPTION_MODE_INVALID != 0);
+
+	/*
+	 * Validate the crypto mode properties.  This ideally would be done with
+	 * static assertions, but boot-time checks are the next best thing.
+	 */
+	for (i = 0; i < BLK_ENCRYPTION_MODE_MAX; i++) {
+		BUG_ON(blk_crypto_modes[i].keysize >
+		       BLK_CRYPTO_MAX_RAW_KEY_SIZE);
+		BUG_ON(blk_crypto_modes[i].security_strength >
+		       blk_crypto_modes[i].keysize);
+		BUG_ON(blk_crypto_modes[i].ivsize > BLK_CRYPTO_MAX_IV_SIZE);
+	}
+
+	return 0;
+out_no_mem:
+	panic("Failed to allocate mem for bio crypt ctxs\n");
+}
+subsys_initcall(bio_crypt_ctx_init);
+
+void bio_crypt_set_ctx(struct bio *bio, const struct blk_crypto_key *key,
+		       const u64 dun[BLK_CRYPTO_DUN_ARRAY_SIZE], gfp_t gfp_mask)
+{
+	struct bio_crypt_ctx *bc;
+
+	/*
+	 * The caller must use a gfp_mask that contains __GFP_DIRECT_RECLAIM so
+	 * that the mempool_alloc() can't fail.
+	 */
+	WARN_ON_ONCE(!(gfp_mask & __GFP_DIRECT_RECLAIM));
+
+	bc = mempool_alloc(bio_crypt_ctx_pool, gfp_mask);
+
+	bc->bc_key = key;
+	memcpy(bc->bc_dun, dun, sizeof(bc->bc_dun));
+
+	bio->bi_crypt_context = bc;
+}
+EXPORT_SYMBOL_GPL(bio_crypt_set_ctx);
+
+void __bio_crypt_free_ctx(struct bio *bio)
+{
+	mempool_free(bio->bi_crypt_context, bio_crypt_ctx_pool);
+	bio->bi_crypt_context = NULL;
+}
+
+int __bio_crypt_clone(struct bio *dst, struct bio *src, gfp_t gfp_mask)
+{
+	dst->bi_crypt_context = mempool_alloc(bio_crypt_ctx_pool, gfp_mask);
+	if (!dst->bi_crypt_context)
+		return -ENOMEM;
+	*dst->bi_crypt_context = *src->bi_crypt_context;
+	return 0;
+}
+
+/* Increments @dun by @inc, treating @dun as a multi-limb integer. */
+void bio_crypt_dun_increment(u64 dun[BLK_CRYPTO_DUN_ARRAY_SIZE],
+			     unsigned int inc)
+{
+	int i;
+
+	for (i = 0; inc && i < BLK_CRYPTO_DUN_ARRAY_SIZE; i++) {
+		dun[i] += inc;
+		/*
+		 * If the addition in this limb overflowed, then we need to
+		 * carry 1 into the next limb. Else the carry is 0.
+		 */
+		if (dun[i] < inc)
+			inc = 1;
+		else
+			inc = 0;
+	}
+}
+
+void __bio_crypt_advance(struct bio *bio, unsigned int bytes)
+{
+	struct bio_crypt_ctx *bc = bio->bi_crypt_context;
+
+	bio_crypt_dun_increment(bc->bc_dun,
+				bytes >> bc->bc_key->data_unit_size_bits);
+}
+
+/*
+ * Returns true if @bc->bc_dun plus @bytes converted to data units is equal to
+ * @next_dun, treating the DUNs as multi-limb integers.
+ */
+bool bio_crypt_dun_is_contiguous(const struct bio_crypt_ctx *bc,
+				 unsigned int bytes,
+				 const u64 next_dun[BLK_CRYPTO_DUN_ARRAY_SIZE])
+{
+	int i;
+	unsigned int carry = bytes >> bc->bc_key->data_unit_size_bits;
+
+	for (i = 0; i < BLK_CRYPTO_DUN_ARRAY_SIZE; i++) {
+		if (bc->bc_dun[i] + carry != next_dun[i])
+			return false;
+		/*
+		 * If the addition in this limb overflowed, then we need to
+		 * carry 1 into the next limb. Else the carry is 0.
+		 */
+		if ((bc->bc_dun[i] + carry) < carry)
+			carry = 1;
+		else
+			carry = 0;
+	}
+
+	/* If the DUN wrapped through 0, don't treat it as contiguous. */
+	return carry == 0;
+}
+
+/*
+ * Checks that two bio crypt contexts are compatible - i.e. that
+ * they are mergeable except for data_unit_num continuity.
+ */
+static bool bio_crypt_ctx_compatible(struct bio_crypt_ctx *bc1,
+				     struct bio_crypt_ctx *bc2)
+{
+	if (!bc1)
+		return !bc2;
+
+	return bc2 && bc1->bc_key == bc2->bc_key;
+}
+
+bool bio_crypt_rq_ctx_compatible(struct request *rq, struct bio *bio)
+{
+	return bio_crypt_ctx_compatible(rq->crypt_ctx, bio->bi_crypt_context);
+}
+
+/*
+ * Checks that two bio crypt contexts are compatible, and also
+ * that their data_unit_nums are continuous (and can hence be merged)
+ * in the order @bc1 followed by @bc2.
+ */
+bool bio_crypt_ctx_mergeable(struct bio_crypt_ctx *bc1, unsigned int bc1_bytes,
+			     struct bio_crypt_ctx *bc2)
+{
+	if (!bio_crypt_ctx_compatible(bc1, bc2))
+		return false;
+
+	return !bc1 || bio_crypt_dun_is_contiguous(bc1, bc1_bytes, bc2->bc_dun);
+}
+
+blk_status_t __blk_crypto_rq_get_keyslot(struct request *rq)
+{
+	return blk_crypto_get_keyslot(rq->q->crypto_profile,
+				      rq->crypt_ctx->bc_key,
+				      &rq->crypt_keyslot);
+}
+
+void __blk_crypto_rq_put_keyslot(struct request *rq)
+{
+	blk_crypto_put_keyslot(rq->crypt_keyslot);
+	rq->crypt_keyslot = NULL;
+}
+
+void __blk_crypto_free_request(struct request *rq)
+{
+	/* The keyslot, if one was needed, should have been released earlier. */
+	if (WARN_ON_ONCE(rq->crypt_keyslot))
+		__blk_crypto_rq_put_keyslot(rq);
+
+	mempool_free(rq->crypt_ctx, bio_crypt_ctx_pool);
+	rq->crypt_ctx = NULL;
+}
+
+/*
+ * Process a bio with a crypto context.  Returns true if the caller should
+ * submit the passed in bio, false if the bio is consumed.
+ *
+ * See the kerneldoc comment for blk_crypto_submit_bio for further details.
+ */
+bool __blk_crypto_submit_bio(struct bio *bio)
+{
+	const struct blk_crypto_key *bc_key = bio->bi_crypt_context->bc_key;
+	struct block_device *bdev = bio->bi_bdev;
+
+	/* Error if bio has no data. */
+	if (WARN_ON_ONCE(!bio_has_data(bio))) {
+		bio_io_error(bio);
+		return false;
+	}
+
+	/*
+	 * If the device does not natively support the encryption context, try to use
+	 * the fallback if available.
+	 */
+	if (!blk_crypto_config_supported_natively(bdev, &bc_key->crypto_cfg)) {
+		if (!IS_ENABLED(CONFIG_BLK_INLINE_ENCRYPTION_FALLBACK)) {
+			pr_warn_once("%pg: crypto API fallback disabled; failing request.\n",
+				bdev);
+			bio_endio_status(bio, BLK_STS_NOTSUPP);
+			return false;
+		}
+		return blk_crypto_fallback_bio_prep(bio);
+	}
+
+	return true;
+}
+EXPORT_SYMBOL_GPL(__blk_crypto_submit_bio);
+
+int __blk_crypto_rq_bio_prep(struct request *rq, struct bio *bio,
+			     gfp_t gfp_mask)
+{
+	if (!rq->crypt_ctx) {
+		rq->crypt_ctx = mempool_alloc(bio_crypt_ctx_pool, gfp_mask);
+		if (!rq->crypt_ctx)
+			return -ENOMEM;
+	}
+	*rq->crypt_ctx = *bio->bi_crypt_context;
+	return 0;
+}
+
+/**
+ * blk_crypto_init_key() - Prepare a key for use with blk-crypto
+ * @blk_key: Pointer to the blk_crypto_key to initialize.
+ * @key_bytes: the bytes of the key
+ * @key_size: size of the key in bytes
+ * @key_type: type of the key -- either raw or hardware-wrapped
+ * @crypto_mode: identifier for the encryption algorithm to use
+ * @dun_bytes: number of bytes that will be used to specify the DUN when this
+ *	       key is used
+ * @data_unit_size: the data unit size to use for en/decryption
+ * @flags: BLK_CRYPTO_CFG_* flags
+ *
+ * Return: 0 on success, -errno on failure.  The caller is responsible for
+ *	   zeroizing both blk_key and key_bytes when done with them.
+ */
+int blk_crypto_init_key(struct blk_crypto_key *blk_key,
+			const u8 *key_bytes, size_t key_size,
+			enum blk_crypto_key_type key_type,
+			enum blk_crypto_mode_num crypto_mode,
+			unsigned int dun_bytes,
+			unsigned int data_unit_size, int flags)
+{
+	const struct blk_crypto_mode *mode;
+
+	memset(blk_key, 0, sizeof(*blk_key));
+
+	if (crypto_mode >= ARRAY_SIZE(blk_crypto_modes))
+		return -EINVAL;
+
+	if (flags & ~BLK_CRYPTO_CFG_ALLOW_HW)
+		return -EINVAL;
+
+	mode = &blk_crypto_modes[crypto_mode];
+	switch (key_type) {
+	case BLK_CRYPTO_KEY_TYPE_RAW:
+		if (key_size != mode->keysize)
+			return -EINVAL;
+		break;
+	case BLK_CRYPTO_KEY_TYPE_HW_WRAPPED:
+		if (key_size < mode->security_strength ||
+		    key_size > BLK_CRYPTO_MAX_HW_WRAPPED_KEY_SIZE)
+			return -EINVAL;
+		if (!(flags & BLK_CRYPTO_CFG_ALLOW_HW))
+			return -EINVAL;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	if (dun_bytes == 0 || dun_bytes > mode->ivsize)
+		return -EINVAL;
+
+	if (!is_power_of_2(data_unit_size))
+		return -EINVAL;
+
+	blk_key->crypto_cfg.crypto_mode = crypto_mode;
+	blk_key->crypto_cfg.dun_bytes = dun_bytes;
+	blk_key->crypto_cfg.data_unit_size = data_unit_size;
+	blk_key->crypto_cfg.key_type = key_type;
+	blk_key->crypto_cfg.flags = flags;
+	blk_key->data_unit_size_bits = ilog2(data_unit_size);
+	blk_key->size = key_size;
+	memcpy(blk_key->bytes, key_bytes, key_size);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(blk_crypto_init_key);
+
+/**
+ * blk_crypto_config_supported_natively() - Check whether a block device
+ *					    supports hardware inline encryption
+ *					    with the given configuration.
+ * @bdev: the block device
+ * @cfg: the crypto configuration to check for
+ *
+ * Return: %true if @bdev supports hardware inline encryption with @cfg.
+ */
+bool blk_crypto_config_supported_natively(struct block_device *bdev,
+					  const struct blk_crypto_config *cfg)
+{
+	struct blk_crypto_profile *profile =
+		bdev_get_queue(bdev)->crypto_profile;
+
+	if (!profile)
+		return false;
+	if (!(cfg->flags & BLK_CRYPTO_CFG_ALLOW_HW))
+		return false;
+	if (!(profile->modes_supported[cfg->crypto_mode] & cfg->data_unit_size))
+		return false;
+	if (profile->max_dun_bytes_supported < cfg->dun_bytes)
+		return false;
+	if (!(profile->key_types_supported & cfg->key_type))
+		return false;
+	return true;
+}
+
+/**
+ * blk_crypto_start_using_key() - Start using a blk_crypto_key on a device
+ * @bdev: block device to operate on
+ * @key: A key to use on the device
+ *
+ * Upper layers must call this function to ensure that either the hardware
+ * supports the key's crypto settings, or the crypto API fallback has transforms
+ * for the needed mode allocated and ready to go. This function may allocate
+ * an skcipher, and *should not* be called from the data path, since that might
+ * cause a deadlock
+ *
+ * Return: 0 on success; -EOPNOTSUPP if the key is wrapped but the hardware does
+ *	   not support wrapped keys; -ENOPKG if the key is a raw key but the
+ *	   hardware does not support raw keys and blk-crypto-fallback is either
+ *	   disabled or the needed algorithm is disabled in the crypto API; or
+ *	   another -errno code if something else went wrong.
+ */
+int blk_crypto_start_using_key(struct block_device *bdev,
+			       const struct blk_crypto_key *key)
+{
+	if (blk_crypto_config_supported_natively(bdev, &key->crypto_cfg))
+		return 0;
+	if (key->crypto_cfg.key_type != BLK_CRYPTO_KEY_TYPE_RAW) {
+		pr_warn_ratelimited("%pg: no support for wrapped keys\n", bdev);
+		return -EOPNOTSUPP;
+	}
+	return blk_crypto_fallback_start_using_mode(key->crypto_cfg.crypto_mode);
+}
+EXPORT_SYMBOL_GPL(blk_crypto_start_using_key);
+
+/**
+ * blk_crypto_evict_key() - Evict a blk_crypto_key from a block_device
+ * @bdev: a block_device on which I/O using the key may have been done
+ * @key: the key to evict
+ *
+ * For a given block_device, this function removes the given blk_crypto_key from
+ * the keyslot management structures and evicts it from any underlying hardware
+ * keyslot(s) or blk-crypto-fallback keyslot it may have been programmed into.
+ *
+ * Upper layers must call this before freeing the blk_crypto_key.  It must be
+ * called for every block_device the key may have been used on.  The key must no
+ * longer be in use by any I/O when this function is called.
+ *
+ * Context: May sleep.
+ */
+void blk_crypto_evict_key(struct block_device *bdev,
+			  const struct blk_crypto_key *key)
+{
+	struct request_queue *q = bdev_get_queue(bdev);
+	int err;
+
+	if (blk_crypto_config_supported_natively(bdev, &key->crypto_cfg))
+		err = __blk_crypto_evict_key(q->crypto_profile, key);
+	else
+		err = blk_crypto_fallback_evict_key(key);
+	/*
+	 * An error can only occur here if the key failed to be evicted from a
+	 * keyslot (due to a hardware or driver issue) or is allegedly still in
+	 * use by I/O (due to a kernel bug).  Even in these cases, the key is
+	 * still unlinked from the keyslot management structures, and the caller
+	 * is allowed and expected to free it right away.  There's nothing
+	 * callers can do to handle errors, so just log them and return void.
+	 */
+	if (err)
+		pr_warn_ratelimited("%pg: error %d evicting key\n", bdev, err);
+}
+EXPORT_SYMBOL_GPL(blk_crypto_evict_key);
+
+static int blk_crypto_ioctl_import_key(struct blk_crypto_profile *profile,
+				       void __user *argp)
+{
+	struct blk_crypto_import_key_arg arg;
+	u8 raw_key[BLK_CRYPTO_MAX_RAW_KEY_SIZE];
+	u8 lt_key[BLK_CRYPTO_MAX_HW_WRAPPED_KEY_SIZE];
+	int ret;
+
+	if (copy_from_user(&arg, argp, sizeof(arg)))
+		return -EFAULT;
+
+	if (memchr_inv(arg.reserved, 0, sizeof(arg.reserved)))
+		return -EINVAL;
+
+	if (arg.raw_key_size < 16 || arg.raw_key_size > sizeof(raw_key))
+		return -EINVAL;
+
+	if (copy_from_user(raw_key, u64_to_user_ptr(arg.raw_key_ptr),
+			   arg.raw_key_size)) {
+		ret = -EFAULT;
+		goto out;
+	}
+	ret = blk_crypto_import_key(profile, raw_key, arg.raw_key_size, lt_key);
+	if (ret < 0)
+		goto out;
+	if (ret > arg.lt_key_size) {
+		ret = -EOVERFLOW;
+		goto out;
+	}
+	arg.lt_key_size = ret;
+	if (copy_to_user(u64_to_user_ptr(arg.lt_key_ptr), lt_key,
+			 arg.lt_key_size) ||
+	    copy_to_user(argp, &arg, sizeof(arg))) {
+		ret = -EFAULT;
+		goto out;
+	}
+	ret = 0;
+
+out:
+	memzero_explicit(raw_key, sizeof(raw_key));
+	memzero_explicit(lt_key, sizeof(lt_key));
+	return ret;
+}
+
+static int blk_crypto_ioctl_generate_key(struct blk_crypto_profile *profile,
+					 void __user *argp)
+{
+	struct blk_crypto_generate_key_arg arg;
+	u8 lt_key[BLK_CRYPTO_MAX_HW_WRAPPED_KEY_SIZE];
+	int ret;
+
+	if (copy_from_user(&arg, argp, sizeof(arg)))
+		return -EFAULT;
+
+	if (memchr_inv(arg.reserved, 0, sizeof(arg.reserved)))
+		return -EINVAL;
+
+	ret = blk_crypto_generate_key(profile, lt_key);
+	if (ret < 0)
+		goto out;
+	if (ret > arg.lt_key_size) {
+		ret = -EOVERFLOW;
+		goto out;
+	}
+	arg.lt_key_size = ret;
+	if (copy_to_user(u64_to_user_ptr(arg.lt_key_ptr), lt_key,
+			 arg.lt_key_size) ||
+	    copy_to_user(argp, &arg, sizeof(arg))) {
+		ret = -EFAULT;
+		goto out;
+	}
+	ret = 0;
+
+out:
+	memzero_explicit(lt_key, sizeof(lt_key));
+	return ret;
+}
+
+static int blk_crypto_ioctl_prepare_key(struct blk_crypto_profile *profile,
+					void __user *argp)
+{
+	struct blk_crypto_prepare_key_arg arg;
+	u8 lt_key[BLK_CRYPTO_MAX_HW_WRAPPED_KEY_SIZE];
+	u8 eph_key[BLK_CRYPTO_MAX_HW_WRAPPED_KEY_SIZE];
+	int ret;
+
+	if (copy_from_user(&arg, argp, sizeof(arg)))
+		return -EFAULT;
+
+	if (memchr_inv(arg.reserved, 0, sizeof(arg.reserved)))
+		return -EINVAL;
+
+	if (arg.lt_key_size > sizeof(lt_key))
+		return -EINVAL;
+
+	if (copy_from_user(lt_key, u64_to_user_ptr(arg.lt_key_ptr),
+			   arg.lt_key_size)) {
+		ret = -EFAULT;
+		goto out;
+	}
+	ret = blk_crypto_prepare_key(profile, lt_key, arg.lt_key_size, eph_key);
+	if (ret < 0)
+		goto out;
+	if (ret > arg.eph_key_size) {
+		ret = -EOVERFLOW;
+		goto out;
+	}
+	arg.eph_key_size = ret;
+	if (copy_to_user(u64_to_user_ptr(arg.eph_key_ptr), eph_key,
+			 arg.eph_key_size) ||
+	    copy_to_user(argp, &arg, sizeof(arg))) {
+		ret = -EFAULT;
+		goto out;
+	}
+	ret = 0;
+
+out:
+	memzero_explicit(lt_key, sizeof(lt_key));
+	memzero_explicit(eph_key, sizeof(eph_key));
+	return ret;
+}
+
+int blk_crypto_ioctl(struct block_device *bdev, unsigned int cmd,
+		     void __user *argp)
+{
+	struct blk_crypto_profile *profile =
+		bdev_get_queue(bdev)->crypto_profile;
+
+	if (!profile)
+		return -EOPNOTSUPP;
+
+	switch (cmd) {
+	case BLKCRYPTOIMPORTKEY:
+		return blk_crypto_ioctl_import_key(profile, argp);
+	case BLKCRYPTOGENERATEKEY:
+		return blk_crypto_ioctl_generate_key(profile, argp);
+	case BLKCRYPTOPREPAREKEY:
+		return blk_crypto_ioctl_prepare_key(profile, argp);
+	default:
+		return -ENOTTY;
+	}
+}