Merge tag 'for-6.8/dm-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper fixes from Mike Snitzer:

 - Stable fixes for 3 DM targets (integrity, verity and crypt) to
   address systemic failure that can occur if user provided pages map to
   the same block.

 - Fix DM crypt to not allow modifying data that being encrypted for
   authenticated encryption.

 - Fix DM crypt and verity targets to align their respective bvec_iter
   struct members to avoid the need for byte level access (due to
   __packed attribute) that is costly on some arches (like RISC).

* tag 'for-6.8/dm-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
  dm-crypt, dm-integrity, dm-verity: bump target version
  dm-verity, dm-crypt: align "struct bvec_iter" correctly
  dm-crypt: recheck the integrity tag after a failure
  dm-crypt: don't modify the data when using authenticated encryption
  dm-verity: recheck the hash after a failure
  dm-integrity: recheck the integrity tag after a failure

4 files changed, 256 insertions, 38 deletions

diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index f745f8508243..59445763e55a 100644
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -53,15 +53,17 @@
 struct convert_context {
 	struct completion restart;
 	struct bio *bio_in;
-	struct bio *bio_out;
 	struct bvec_iter iter_in;
+	struct bio *bio_out;
 	struct bvec_iter iter_out;
-	u64 cc_sector;
 	atomic_t cc_pending;
+	u64 cc_sector;
 	union {
 		struct skcipher_request *req;
 		struct aead_request *req_aead;
 	} r;
+	bool aead_recheck;
+	bool aead_failed;
 
 };
 
@@ -82,6 +84,8 @@ struct dm_crypt_io {
 	blk_status_t error;
 	sector_t sector;
 
+	struct bvec_iter saved_bi_iter;
+
 	struct rb_node rb_node;
 } CRYPTO_MINALIGN_ATTR;
 
@@ -1370,10 +1374,13 @@ static int crypt_convert_block_aead(struct crypt_config *cc,
 	if (r == -EBADMSG) {
 		sector_t s = le64_to_cpu(*sector);
 
-		DMERR_LIMIT("%pg: INTEGRITY AEAD ERROR, sector %llu",
-			    ctx->bio_in->bi_bdev, s);
-		dm_audit_log_bio(DM_MSG_PREFIX, "integrity-aead",
-				 ctx->bio_in, s, 0);
+		ctx->aead_failed = true;
+		if (ctx->aead_recheck) {
+			DMERR_LIMIT("%pg: INTEGRITY AEAD ERROR, sector %llu",
+				    ctx->bio_in->bi_bdev, s);
+			dm_audit_log_bio(DM_MSG_PREFIX, "integrity-aead",
+					 ctx->bio_in, s, 0);
+		}
 	}
 
 	if (!r && cc->iv_gen_ops && cc->iv_gen_ops->post)
@@ -1757,6 +1764,8 @@ static void crypt_io_init(struct dm_crypt_io *io, struct crypt_config *cc,
 	io->base_bio = bio;
 	io->sector = sector;
 	io->error = 0;
+	io->ctx.aead_recheck = false;
+	io->ctx.aead_failed = false;
 	io->ctx.r.req = NULL;
 	io->integrity_metadata = NULL;
 	io->integrity_metadata_from_pool = false;
@@ -1768,6 +1777,8 @@ static void crypt_inc_pending(struct dm_crypt_io *io)
 	atomic_inc(&io->io_pending);
 }
 
+static void kcryptd_queue_read(struct dm_crypt_io *io);
+
 /*
  * One of the bios was finished. Check for completion of
  * the whole request and correctly clean up the buffer.
@@ -1781,6 +1792,15 @@ static void crypt_dec_pending(struct dm_crypt_io *io)
 	if (!atomic_dec_and_test(&io->io_pending))
 		return;
 
+	if (likely(!io->ctx.aead_recheck) && unlikely(io->ctx.aead_failed) &&
+	    cc->on_disk_tag_size && bio_data_dir(base_bio) == READ) {
+		io->ctx.aead_recheck = true;
+		io->ctx.aead_failed = false;
+		io->error = 0;
+		kcryptd_queue_read(io);
+		return;
+	}
+
 	if (io->ctx.r.req)
 		crypt_free_req(cc, io->ctx.r.req, base_bio);
 
@@ -1816,15 +1836,19 @@ static void crypt_endio(struct bio *clone)
 	struct dm_crypt_io *io = clone->bi_private;
 	struct crypt_config *cc = io->cc;
 	unsigned int rw = bio_data_dir(clone);
-	blk_status_t error;
+	blk_status_t error = clone->bi_status;
+
+	if (io->ctx.aead_recheck && !error) {
+		kcryptd_queue_crypt(io);
+		return;
+	}
 
 	/*
 	 * free the processed pages
 	 */
-	if (rw == WRITE)
+	if (rw == WRITE || io->ctx.aead_recheck)
 		crypt_free_buffer_pages(cc, clone);
 
-	error = clone->bi_status;
 	bio_put(clone);
 
 	if (rw == READ && !error) {
@@ -1845,6 +1869,22 @@ static int kcryptd_io_read(struct dm_crypt_io *io, gfp_t gfp)
 	struct crypt_config *cc = io->cc;
 	struct bio *clone;
 
+	if (io->ctx.aead_recheck) {
+		if (!(gfp & __GFP_DIRECT_RECLAIM))
+			return 1;
+		crypt_inc_pending(io);
+		clone = crypt_alloc_buffer(io, io->base_bio->bi_iter.bi_size);
+		if (unlikely(!clone)) {
+			crypt_dec_pending(io);
+			return 1;
+		}
+		clone->bi_iter.bi_sector = cc->start + io->sector;
+		crypt_convert_init(cc, &io->ctx, clone, clone, io->sector);
+		io->saved_bi_iter = clone->bi_iter;
+		dm_submit_bio_remap(io->base_bio, clone);
+		return 0;
+	}
+
 	/*
 	 * We need the original biovec array in order to decrypt the whole bio
 	 * data *afterwards* -- thanks to immutable biovecs we don't need to
@@ -2071,6 +2111,12 @@ static void kcryptd_crypt_write_convert(struct dm_crypt_io *io)
 	io->ctx.bio_out = clone;
 	io->ctx.iter_out = clone->bi_iter;
 
+	if (crypt_integrity_aead(cc)) {
+		bio_copy_data(clone, io->base_bio);
+		io->ctx.bio_in = clone;
+		io->ctx.iter_in = clone->bi_iter;
+	}
+
 	sector += bio_sectors(clone);
 
 	crypt_inc_pending(io);
@@ -2107,6 +2153,14 @@ dec:
 
 static void kcryptd_crypt_read_done(struct dm_crypt_io *io)
 {
+	if (io->ctx.aead_recheck) {
+		if (!io->error) {
+			io->ctx.bio_in->bi_iter = io->saved_bi_iter;
+			bio_copy_data(io->base_bio, io->ctx.bio_in);
+		}
+		crypt_free_buffer_pages(io->cc, io->ctx.bio_in);
+		bio_put(io->ctx.bio_in);
+	}
 	crypt_dec_pending(io);
 }
 
@@ -2136,11 +2190,17 @@ static void kcryptd_crypt_read_convert(struct dm_crypt_io *io)
 
 	crypt_inc_pending(io);
 
-	crypt_convert_init(cc, &io->ctx, io->base_bio, io->base_bio,
-			   io->sector);
+	if (io->ctx.aead_recheck) {
+		io->ctx.cc_sector = io->sector + cc->iv_offset;
+		r = crypt_convert(cc, &io->ctx,
+				  test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags), true);
+	} else {
+		crypt_convert_init(cc, &io->ctx, io->base_bio, io->base_bio,
+				   io->sector);
 
-	r = crypt_convert(cc, &io->ctx,
-			  test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags), true);
+		r = crypt_convert(cc, &io->ctx,
+				  test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags), true);
+	}
 	/*
 	 * Crypto API backlogged the request, because its queue was full
 	 * and we're in softirq context, so continue from a workqueue
@@ -2182,10 +2242,13 @@ static void kcryptd_async_done(void *data, int error)
 	if (error == -EBADMSG) {
 		sector_t s = le64_to_cpu(*org_sector_of_dmreq(cc, dmreq));
 
-		DMERR_LIMIT("%pg: INTEGRITY AEAD ERROR, sector %llu",
-			    ctx->bio_in->bi_bdev, s);
-		dm_audit_log_bio(DM_MSG_PREFIX, "integrity-aead",
-				 ctx->bio_in, s, 0);
+		ctx->aead_failed = true;
+		if (ctx->aead_recheck) {
+			DMERR_LIMIT("%pg: INTEGRITY AEAD ERROR, sector %llu",
+				    ctx->bio_in->bi_bdev, s);
+			dm_audit_log_bio(DM_MSG_PREFIX, "integrity-aead",
+					 ctx->bio_in, s, 0);
+		}
 		io->error = BLK_STS_PROTECTION;
 	} else if (error < 0)
 		io->error = BLK_STS_IOERR;
@@ -3110,7 +3173,7 @@ static int crypt_ctr_optional(struct dm_target *ti, unsigned int argc, char **ar
 			sval = strchr(opt_string + strlen("integrity:"), ':') + 1;
 			if (!strcasecmp(sval, "aead")) {
 				set_bit(CRYPT_MODE_INTEGRITY_AEAD, &cc->cipher_flags);
-			} else  if (strcasecmp(sval, "none")) {
+			} else if (strcasecmp(sval, "none")) {
 				ti->error = "Unknown integrity profile";
 				return -EINVAL;
 			}
@@ -3639,7 +3702,7 @@ static void crypt_io_hints(struct dm_target *ti, struct queue_limits *limits)
 
 static struct target_type crypt_target = {
 	.name   = "crypt",
-	.version = {1, 24, 0},
+	.version = {1, 25, 0},
 	.module = THIS_MODULE,
 	.ctr    = crypt_ctr,
 	.dtr    = crypt_dtr,
diff --git a/drivers/md/dm-integrity.c b/drivers/md/dm-integrity.c
index c5f03aab4552..44a1dcc06dd7 100644
--- a/drivers/md/dm-integrity.c
+++ b/drivers/md/dm-integrity.c
@@ -278,6 +278,8 @@ struct dm_integrity_c {
 
 	atomic64_t number_of_mismatches;
 
+	mempool_t recheck_pool;
+
 	struct notifier_block reboot_notifier;
 };
 
@@ -1689,6 +1691,79 @@ failed:
 	get_random_bytes(result, ic->tag_size);
 }
 
+static void integrity_recheck(struct dm_integrity_io *dio)
+{
+	struct bio *bio = dm_bio_from_per_bio_data(dio, sizeof(struct dm_integrity_io));
+	struct dm_integrity_c *ic = dio->ic;
+	struct bvec_iter iter;
+	struct bio_vec bv;
+	sector_t sector, logical_sector, area, offset;
+	char checksum_onstack[max_t(size_t, HASH_MAX_DIGESTSIZE, MAX_TAG_SIZE)];
+	struct page *page;
+	void *buffer;
+
+	get_area_and_offset(ic, dio->range.logical_sector, &area, &offset);
+	dio->metadata_block = get_metadata_sector_and_offset(ic, area, offset,
+							     &dio->metadata_offset);
+	sector = get_data_sector(ic, area, offset);
+	logical_sector = dio->range.logical_sector;
+
+	page = mempool_alloc(&ic->recheck_pool, GFP_NOIO);
+	buffer = page_to_virt(page);
+
+	__bio_for_each_segment(bv, bio, iter, dio->bio_details.bi_iter) {
+		unsigned pos = 0;
+
+		do {
+			char *mem;
+			int r;
+			struct dm_io_request io_req;
+			struct dm_io_region io_loc;
+			io_req.bi_opf = REQ_OP_READ;
+			io_req.mem.type = DM_IO_KMEM;
+			io_req.mem.ptr.addr = buffer;
+			io_req.notify.fn = NULL;
+			io_req.client = ic->io;
+			io_loc.bdev = ic->dev->bdev;
+			io_loc.sector = sector;
+			io_loc.count = ic->sectors_per_block;
+
+			r = dm_io(&io_req, 1, &io_loc, NULL);
+			if (unlikely(r)) {
+				dio->bi_status = errno_to_blk_status(r);
+				goto free_ret;
+			}
+
+			integrity_sector_checksum(ic, logical_sector, buffer,
+						  checksum_onstack);
+			r = dm_integrity_rw_tag(ic, checksum_onstack, &dio->metadata_block,
+						&dio->metadata_offset, ic->tag_size, TAG_CMP);
+			if (r) {
+				if (r > 0) {
+					DMERR_LIMIT("%pg: Checksum failed at sector 0x%llx",
+						    bio->bi_bdev, logical_sector);
+					atomic64_inc(&ic->number_of_mismatches);
+					dm_audit_log_bio(DM_MSG_PREFIX, "integrity-checksum",
+							 bio, logical_sector, 0);
+					r = -EILSEQ;
+				}
+				dio->bi_status = errno_to_blk_status(r);
+				goto free_ret;
+			}
+
+			mem = bvec_kmap_local(&bv);
+			memcpy(mem + pos, buffer, ic->sectors_per_block << SECTOR_SHIFT);
+			kunmap_local(mem);
+
+			pos += ic->sectors_per_block << SECTOR_SHIFT;
+			sector += ic->sectors_per_block;
+			logical_sector += ic->sectors_per_block;
+		} while (pos < bv.bv_len);
+	}
+free_ret:
+	mempool_free(page, &ic->recheck_pool);
+}
+
 static void integrity_metadata(struct work_struct *w)
 {
 	struct dm_integrity_io *dio = container_of(w, struct dm_integrity_io, work);
@@ -1776,15 +1851,8 @@ again:
 						checksums_ptr - checksums, dio->op == REQ_OP_READ ? TAG_CMP : TAG_WRITE);
 			if (unlikely(r)) {
 				if (r > 0) {
-					sector_t s;
-
-					s = sector - ((r + ic->tag_size - 1) / ic->tag_size);
-					DMERR_LIMIT("%pg: Checksum failed at sector 0x%llx",
-						    bio->bi_bdev, s);
-					r = -EILSEQ;
-					atomic64_inc(&ic->number_of_mismatches);
-					dm_audit_log_bio(DM_MSG_PREFIX, "integrity-checksum",
-							 bio, s, 0);
+					integrity_recheck(dio);
+					goto skip_io;
 				}
 				if (likely(checksums != checksums_onstack))
 					kfree(checksums);
@@ -4261,6 +4329,12 @@ static int dm_integrity_ctr(struct dm_target *ti, unsigned int argc, char **argv
 		goto bad;
 	}
 
+	r = mempool_init_page_pool(&ic->recheck_pool, 1, 0);
+	if (r) {
+		ti->error = "Cannot allocate mempool";
+		goto bad;
+	}
+
 	ic->metadata_wq = alloc_workqueue("dm-integrity-metadata",
 					  WQ_MEM_RECLAIM, METADATA_WORKQUEUE_MAX_ACTIVE);
 	if (!ic->metadata_wq) {
@@ -4609,6 +4683,7 @@ static void dm_integrity_dtr(struct dm_target *ti)
 	kvfree(ic->bbs);
 	if (ic->bufio)
 		dm_bufio_client_destroy(ic->bufio);
+	mempool_exit(&ic->recheck_pool);
 	mempool_exit(&ic->journal_io_mempool);
 	if (ic->io)
 		dm_io_client_destroy(ic->io);
@@ -4661,7 +4736,7 @@ static void dm_integrity_dtr(struct dm_target *ti)
 
 static struct target_type integrity_target = {
 	.name			= "integrity",
-	.version		= {1, 10, 0},
+	.version		= {1, 11, 0},
 	.module			= THIS_MODULE,
 	.features		= DM_TARGET_SINGLETON | DM_TARGET_INTEGRITY,
 	.ctr			= dm_integrity_ctr,
diff --git a/drivers/md/dm-verity-target.c b/drivers/md/dm-verity-target.c
index 82662f5769c4..06c8b637849c 100644
--- a/drivers/md/dm-verity-target.c
+++ b/drivers/md/dm-verity-target.c
@@ -482,6 +482,63 @@ int verity_for_bv_block(struct dm_verity *v, struct dm_verity_io *io,
 	return 0;
 }
 
+static int verity_recheck_copy(struct dm_verity *v, struct dm_verity_io *io,
+			       u8 *data, size_t len)
+{
+	memcpy(data, io->recheck_buffer, len);
+	io->recheck_buffer += len;
+
+	return 0;
+}
+
+static int verity_recheck(struct dm_verity *v, struct dm_verity_io *io,
+			  struct bvec_iter start, sector_t cur_block)
+{
+	struct page *page;
+	void *buffer;
+	int r;
+	struct dm_io_request io_req;
+	struct dm_io_region io_loc;
+
+	page = mempool_alloc(&v->recheck_pool, GFP_NOIO);
+	buffer = page_to_virt(page);
+
+	io_req.bi_opf = REQ_OP_READ;
+	io_req.mem.type = DM_IO_KMEM;
+	io_req.mem.ptr.addr = buffer;
+	io_req.notify.fn = NULL;
+	io_req.client = v->io;
+	io_loc.bdev = v->data_dev->bdev;
+	io_loc.sector = cur_block << (v->data_dev_block_bits - SECTOR_SHIFT);
+	io_loc.count = 1 << (v->data_dev_block_bits - SECTOR_SHIFT);
+	r = dm_io(&io_req, 1, &io_loc, NULL);
+	if (unlikely(r))
+		goto free_ret;
+
+	r = verity_hash(v, verity_io_hash_req(v, io), buffer,
+			1 << v->data_dev_block_bits,
+			verity_io_real_digest(v, io), true);
+	if (unlikely(r))
+		goto free_ret;
+
+	if (memcmp(verity_io_real_digest(v, io),
+		   verity_io_want_digest(v, io), v->digest_size)) {
+		r = -EIO;
+		goto free_ret;
+	}
+
+	io->recheck_buffer = buffer;
+	r = verity_for_bv_block(v, io, &start, verity_recheck_copy);
+	if (unlikely(r))
+		goto free_ret;
+
+	r = 0;
+free_ret:
+	mempool_free(page, &v->recheck_pool);
+
+	return r;
+}
+
 static int verity_bv_zero(struct dm_verity *v, struct dm_verity_io *io,
 			  u8 *data, size_t len)
 {
@@ -508,9 +565,7 @@ static int verity_verify_io(struct dm_verity_io *io)
 {
 	bool is_zero;
 	struct dm_verity *v = io->v;
-#if defined(CONFIG_DM_VERITY_FEC)
 	struct bvec_iter start;
-#endif
 	struct bvec_iter iter_copy;
 	struct bvec_iter *iter;
 	struct crypto_wait wait;
@@ -561,10 +616,7 @@ static int verity_verify_io(struct dm_verity_io *io)
 		if (unlikely(r < 0))
 			return r;
 
-#if defined(CONFIG_DM_VERITY_FEC)
-		if (verity_fec_is_enabled(v))
-			start = *iter;
-#endif
+		start = *iter;
 		r = verity_for_io_block(v, io, iter, &wait);
 		if (unlikely(r < 0))
 			return r;
@@ -586,6 +638,10 @@ static int verity_verify_io(struct dm_verity_io *io)
 			 * tasklet since it may sleep, so fallback to work-queue.
 			 */
 			return -EAGAIN;
+		} else if (verity_recheck(v, io, start, cur_block) == 0) {
+			if (v->validated_blocks)
+				set_bit(cur_block, v->validated_blocks);
+			continue;
 #if defined(CONFIG_DM_VERITY_FEC)
 		} else if (verity_fec_decode(v, io, DM_VERITY_BLOCK_TYPE_DATA,
 					     cur_block, NULL, &start) == 0) {
@@ -941,6 +997,10 @@ static void verity_dtr(struct dm_target *ti)
 	if (v->verify_wq)
 		destroy_workqueue(v->verify_wq);
 
+	mempool_exit(&v->recheck_pool);
+	if (v->io)
+		dm_io_client_destroy(v->io);
+
 	if (v->bufio)
 		dm_bufio_client_destroy(v->bufio);
 
@@ -1379,6 +1439,20 @@ static int verity_ctr(struct dm_target *ti, unsigned int argc, char **argv)
 	}
 	v->hash_blocks = hash_position;
 
+	r = mempool_init_page_pool(&v->recheck_pool, 1, 0);
+	if (unlikely(r)) {
+		ti->error = "Cannot allocate mempool";
+		goto bad;
+	}
+
+	v->io = dm_io_client_create();
+	if (IS_ERR(v->io)) {
+		r = PTR_ERR(v->io);
+		v->io = NULL;
+		ti->error = "Cannot allocate dm io";
+		goto bad;
+	}
+
 	v->bufio = dm_bufio_client_create(v->hash_dev->bdev,
 		1 << v->hash_dev_block_bits, 1, sizeof(struct buffer_aux),
 		dm_bufio_alloc_callback, NULL,
@@ -1486,7 +1560,7 @@ int dm_verity_get_root_digest(struct dm_target *ti, u8 **root_digest, unsigned i
 static struct target_type verity_target = {
 	.name		= "verity",
 	.features	= DM_TARGET_IMMUTABLE,
-	.version	= {1, 9, 0},
+	.version	= {1, 10, 0},
 	.module		= THIS_MODULE,
 	.ctr		= verity_ctr,
 	.dtr		= verity_dtr,
diff --git a/drivers/md/dm-verity.h b/drivers/md/dm-verity.h
index f3f607008419..db93a91169d5 100644
--- a/drivers/md/dm-verity.h
+++ b/drivers/md/dm-verity.h
@@ -11,6 +11,7 @@
 #ifndef DM_VERITY_H
 #define DM_VERITY_H
 
+#include <linux/dm-io.h>
 #include <linux/dm-bufio.h>
 #include <linux/device-mapper.h>
 #include <linux/interrupt.h>
@@ -68,6 +69,9 @@ struct dm_verity {
 	unsigned long *validated_blocks; /* bitset blocks validated */
 
 	char *signature_key_desc; /* signature keyring reference */
+
+	struct dm_io_client *io;
+	mempool_t recheck_pool;
 };
 
 struct dm_verity_io {
@@ -76,14 +80,16 @@ struct dm_verity_io {
 	/* original value of bio->bi_end_io */
 	bio_end_io_t *orig_bi_end_io;
 
+	struct bvec_iter iter;
+
 	sector_t block;
 	unsigned int n_blocks;
 	bool in_tasklet;
 
-	struct bvec_iter iter;
-
 	struct work_struct work;
 
+	char *recheck_buffer;
+
 	/*
 	 * Three variably-size fields follow this struct:
 	 *