1 files changed, 86 insertions, 38 deletions

diff --git a/fs/buffer.c b/fs/buffer.c
index d9c6d1fbb6dd..9e1e2add541e 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -48,6 +48,7 @@
 #include <linux/sched/mm.h>
 #include <trace/events/block.h>
 #include <linux/fscrypt.h>
+#include <linux/fsverity.h>
 
 #include "internal.h"
 
@@ -60,7 +61,7 @@ static void submit_bh_wbc(blk_opf_t opf, struct buffer_head *bh,
 inline void touch_buffer(struct buffer_head *bh)
 {
 	trace_block_touch_buffer(bh);
-	mark_page_accessed(bh->b_page);
+	folio_mark_accessed(bh->b_folio);
 }
 EXPORT_SYMBOL(touch_buffer);
 
@@ -246,18 +247,18 @@ static void end_buffer_async_read(struct buffer_head *bh, int uptodate)
 	unsigned long flags;
 	struct buffer_head *first;
 	struct buffer_head *tmp;
-	struct page *page;
-	int page_uptodate = 1;
+	struct folio *folio;
+	int folio_uptodate = 1;
 
 	BUG_ON(!buffer_async_read(bh));
 
-	page = bh->b_page;
+	folio = bh->b_folio;
 	if (uptodate) {
 		set_buffer_uptodate(bh);
 	} else {
 		clear_buffer_uptodate(bh);
 		buffer_io_error(bh, ", async page read");
-		SetPageError(page);
+		folio_set_error(folio);
 	}
 
 	/*
@@ -265,14 +266,14 @@ static void end_buffer_async_read(struct buffer_head *bh, int uptodate)
 	 * two buffer heads end IO at almost the same time and both
 	 * decide that the page is now completely done.
 	 */
-	first = page_buffers(page);
+	first = folio_buffers(folio);
 	spin_lock_irqsave(&first->b_uptodate_lock, flags);
 	clear_buffer_async_read(bh);
 	unlock_buffer(bh);
 	tmp = bh;
 	do {
 		if (!buffer_uptodate(tmp))
-			page_uptodate = 0;
+			folio_uptodate = 0;
 		if (buffer_async_read(tmp)) {
 			BUG_ON(!buffer_locked(tmp));
 			goto still_busy;
@@ -285,9 +286,9 @@ static void end_buffer_async_read(struct buffer_head *bh, int uptodate)
 	 * If all of the buffers are uptodate then we can set the page
 	 * uptodate.
 	 */
-	if (page_uptodate)
-		SetPageUptodate(page);
-	unlock_page(page);
+	if (folio_uptodate)
+		folio_mark_uptodate(folio);
+	folio_unlock(folio);
 	return;
 
 still_busy:
@@ -295,20 +296,53 @@ still_busy:
 	return;
 }
 
-struct decrypt_bh_ctx {
+struct postprocess_bh_ctx {
 	struct work_struct work;
 	struct buffer_head *bh;
 };
 
+static void verify_bh(struct work_struct *work)
+{
+	struct postprocess_bh_ctx *ctx =
+		container_of(work, struct postprocess_bh_ctx, work);
+	struct buffer_head *bh = ctx->bh;
+	bool valid;
+
+	valid = fsverity_verify_blocks(page_folio(bh->b_page), bh->b_size,
+				       bh_offset(bh));
+	end_buffer_async_read(bh, valid);
+	kfree(ctx);
+}
+
+static bool need_fsverity(struct buffer_head *bh)
+{
+	struct page *page = bh->b_page;
+	struct inode *inode = page->mapping->host;
+
+	return fsverity_active(inode) &&
+		/* needed by ext4 */
+		page->index < DIV_ROUND_UP(inode->i_size, PAGE_SIZE);
+}
+
 static void decrypt_bh(struct work_struct *work)
 {
-	struct decrypt_bh_ctx *ctx =
-		container_of(work, struct decrypt_bh_ctx, work);
+	struct postprocess_bh_ctx *ctx =
+		container_of(work, struct postprocess_bh_ctx, work);
 	struct buffer_head *bh = ctx->bh;
 	int err;
 
-	err = fscrypt_decrypt_pagecache_blocks(bh->b_page, bh->b_size,
-					       bh_offset(bh));
+	err = fscrypt_decrypt_pagecache_blocks(page_folio(bh->b_page),
+					       bh->b_size, bh_offset(bh));
+	if (err == 0 && need_fsverity(bh)) {
+		/*
+		 * We use different work queues for decryption and for verity
+		 * because verity may require reading metadata pages that need
+		 * decryption, and we shouldn't recurse to the same workqueue.
+		 */
+		INIT_WORK(&ctx->work, verify_bh);
+		fsverity_enqueue_verify_work(&ctx->work);
+		return;
+	}
 	end_buffer_async_read(bh, err == 0);
 	kfree(ctx);
 }
@@ -319,15 +353,24 @@ static void decrypt_bh(struct work_struct *work)
  */
 static void end_buffer_async_read_io(struct buffer_head *bh, int uptodate)
 {
-	/* Decrypt if needed */
-	if (uptodate &&
-	    fscrypt_inode_uses_fs_layer_crypto(bh->b_page->mapping->host)) {
-		struct decrypt_bh_ctx *ctx = kmalloc(sizeof(*ctx), GFP_ATOMIC);
+	struct inode *inode = bh->b_folio->mapping->host;
+	bool decrypt = fscrypt_inode_uses_fs_layer_crypto(inode);
+	bool verify = need_fsverity(bh);
+
+	/* Decrypt (with fscrypt) and/or verify (with fsverity) if needed. */
+	if (uptodate && (decrypt || verify)) {
+		struct postprocess_bh_ctx *ctx =
+			kmalloc(sizeof(*ctx), GFP_ATOMIC);
 
 		if (ctx) {
-			INIT_WORK(&ctx->work, decrypt_bh);
 			ctx->bh = bh;
-			fscrypt_enqueue_decrypt_work(&ctx->work);
+			if (decrypt) {
+				INIT_WORK(&ctx->work, decrypt_bh);
+				fscrypt_enqueue_decrypt_work(&ctx->work);
+			} else {
+				INIT_WORK(&ctx->work, verify_bh);
+				fsverity_enqueue_verify_work(&ctx->work);
+			}
 			return;
 		}
 		uptodate = 0;
@@ -344,21 +387,21 @@ void end_buffer_async_write(struct buffer_head *bh, int uptodate)
 	unsigned long flags;
 	struct buffer_head *first;
 	struct buffer_head *tmp;
-	struct page *page;
+	struct folio *folio;
 
 	BUG_ON(!buffer_async_write(bh));
 
-	page = bh->b_page;
+	folio = bh->b_folio;
 	if (uptodate) {
 		set_buffer_uptodate(bh);
 	} else {
 		buffer_io_error(bh, ", lost async page write");
 		mark_buffer_write_io_error(bh);
 		clear_buffer_uptodate(bh);
-		SetPageError(page);
+		folio_set_error(folio);
 	}
 
-	first = page_buffers(page);
+	first = folio_buffers(folio);
 	spin_lock_irqsave(&first->b_uptodate_lock, flags);
 
 	clear_buffer_async_write(bh);
@@ -372,7 +415,7 @@ void end_buffer_async_write(struct buffer_head *bh, int uptodate)
 		tmp = tmp->b_this_page;
 	}
 	spin_unlock_irqrestore(&first->b_uptodate_lock, flags);
-	end_page_writeback(page);
+	folio_end_writeback(folio);
 	return;
 
 still_busy:
@@ -570,7 +613,7 @@ void write_boundary_block(struct block_device *bdev,
 void mark_buffer_dirty_inode(struct buffer_head *bh, struct inode *inode)
 {
 	struct address_space *mapping = inode->i_mapping;
-	struct address_space *buffer_mapping = bh->b_page->mapping;
+	struct address_space *buffer_mapping = bh->b_folio->mapping;
 
 	mark_buffer_dirty(bh);
 	if (!mapping->private_data) {
@@ -1073,7 +1116,7 @@ __getblk_slow(struct block_device *bdev, sector_t block,
  * and then attach the address_space's inode to its superblock's dirty
  * inode list.
  *
- * mark_buffer_dirty() is atomic.  It takes bh->b_page->mapping->private_lock,
+ * mark_buffer_dirty() is atomic.  It takes bh->b_folio->mapping->private_lock,
  * i_pages lock and mapping->host->i_lock.
  */
 void mark_buffer_dirty(struct buffer_head *bh)
@@ -1095,16 +1138,16 @@ void mark_buffer_dirty(struct buffer_head *bh)
 	}
 
 	if (!test_set_buffer_dirty(bh)) {
-		struct page *page = bh->b_page;
+		struct folio *folio = bh->b_folio;
 		struct address_space *mapping = NULL;
 
-		lock_page_memcg(page);
-		if (!TestSetPageDirty(page)) {
-			mapping = page_mapping(page);
+		folio_memcg_lock(folio);
+		if (!folio_test_set_dirty(folio)) {
+			mapping = folio->mapping;
 			if (mapping)
-				__set_page_dirty(page, mapping, 0);
+				__folio_mark_dirty(folio, mapping, 0);
 		}
-		unlock_page_memcg(page);
+		folio_memcg_unlock(folio);
 		if (mapping)
 			__mark_inode_dirty(mapping->host, I_DIRTY_PAGES);
 	}
@@ -1117,8 +1160,8 @@ void mark_buffer_write_io_error(struct buffer_head *bh)
 
 	set_buffer_write_io_error(bh);
 	/* FIXME: do we need to set this in both places? */
-	if (bh->b_page && bh->b_page->mapping)
-		mapping_set_error(bh->b_page->mapping, -EIO);
+	if (bh->b_folio && bh->b_folio->mapping)
+		mapping_set_error(bh->b_folio->mapping, -EIO);
 	if (bh->b_assoc_map)
 		mapping_set_error(bh->b_assoc_map, -EIO);
 	rcu_read_lock();
@@ -1154,7 +1197,7 @@ void __bforget(struct buffer_head *bh)
 {
 	clear_buffer_dirty(bh);
 	if (bh->b_assoc_map) {
-		struct address_space *buffer_mapping = bh->b_page->mapping;
+		struct address_space *buffer_mapping = bh->b_folio->mapping;
 
 		spin_lock(&buffer_mapping->private_lock);
 		list_del_init(&bh->b_assoc_buffers);
@@ -2245,6 +2288,11 @@ int block_read_full_folio(struct folio *folio, get_block_t *get_block)
 	int nr, i;
 	int fully_mapped = 1;
 	bool page_error = false;
+	loff_t limit = i_size_read(inode);
+
+	/* This is needed for ext4. */
+	if (IS_ENABLED(CONFIG_FS_VERITY) && IS_VERITY(inode))
+		limit = inode->i_sb->s_maxbytes;
 
 	VM_BUG_ON_FOLIO(folio_test_large(folio), folio);
 
@@ -2253,7 +2301,7 @@ int block_read_full_folio(struct folio *folio, get_block_t *get_block)
 	bbits = block_size_bits(blocksize);
 
 	iblock = (sector_t)folio->index << (PAGE_SHIFT - bbits);
-	lblock = (i_size_read(inode)+blocksize-1) >> bbits;
+	lblock = (limit+blocksize-1) >> bbits;
 	bh = head;
 	nr = 0;
 	i = 0;