From 085aa9f46f24a83208a039bb164f124d6a398bbf Mon Sep 17 00:00:00 2001
From: Sasha Levin <sashal@kernel.org>
Date: Mon, 10 May 2021 17:30:32 +0800
Subject: f2fs: compress: fix to assign cc.cluster_idx correctly

From: Chao Yu <yuchao0@huawei.com>

[ Upstream commit 8bfbfb0ddd706b1ce2e89259ecc45f192c0ec2bf ]

In f2fs_destroy_compress_ctx(), after f2fs_destroy_compress_ctx(),
cc.cluster_idx will be cleared w/ NULL_CLUSTER, f2fs_cluster_blocks()
may check wrong cluster metadata, fix it.

Fixes: 4c8ff7095bef ("f2fs: support data compression")
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 fs/f2fs/compress.c | 17 +++++++++--------
 fs/f2fs/data.c     |  6 +++---
 fs/f2fs/f2fs.h     |  2 +-
 3 files changed, 13 insertions(+), 12 deletions(-)

diff --git a/fs/f2fs/compress.c b/fs/f2fs/compress.c
index 58eb5eefe268..f94b13075ea4 100644
--- a/fs/f2fs/compress.c
+++ b/fs/f2fs/compress.c
@@ -151,13 +151,14 @@ int f2fs_init_compress_ctx(struct compress_ctx *cc)
 	return cc->rpages ? 0 : -ENOMEM;
 }
 
-void f2fs_destroy_compress_ctx(struct compress_ctx *cc)
+void f2fs_destroy_compress_ctx(struct compress_ctx *cc, bool reuse)
 {
 	page_array_free(cc->inode, cc->rpages, cc->cluster_size);
 	cc->rpages = NULL;
 	cc->nr_rpages = 0;
 	cc->nr_cpages = 0;
-	cc->cluster_idx = NULL_CLUSTER;
+	if (!reuse)
+		cc->cluster_idx = NULL_CLUSTER;
 }
 
 void f2fs_compress_ctx_add_page(struct compress_ctx *cc, struct page *page)
@@ -984,7 +985,7 @@ static int prepare_compress_overwrite(struct compress_ctx *cc,
 		ret = f2fs_read_multi_pages(cc, &bio, cc->cluster_size,
 					&last_block_in_bio, false, true);
 		f2fs_put_rpages(cc);
-		f2fs_destroy_compress_ctx(cc);
+		f2fs_destroy_compress_ctx(cc, true);
 		if (ret)
 			goto out;
 		if (bio)
@@ -1011,7 +1012,7 @@ static int prepare_compress_overwrite(struct compress_ctx *cc,
 release_and_retry:
 			f2fs_put_rpages(cc);
 			f2fs_unlock_rpages(cc, i + 1);
-			f2fs_destroy_compress_ctx(cc);
+			f2fs_destroy_compress_ctx(cc, true);
 			goto retry;
 		}
 	}
@@ -1044,7 +1045,7 @@ static int prepare_compress_overwrite(struct compress_ctx *cc,
 unlock_pages:
 	f2fs_put_rpages(cc);
 	f2fs_unlock_rpages(cc, i);
-	f2fs_destroy_compress_ctx(cc);
+	f2fs_destroy_compress_ctx(cc, true);
 out:
 	return ret;
 }
@@ -1080,7 +1081,7 @@ bool f2fs_compress_write_end(struct inode *inode, void *fsdata,
 		set_cluster_dirty(&cc);
 
 	f2fs_put_rpages_wbc(&cc, NULL, false, 1);
-	f2fs_destroy_compress_ctx(&cc);
+	f2fs_destroy_compress_ctx(&cc, false);
 
 	return first_index;
 }
@@ -1299,7 +1300,7 @@ static int f2fs_write_compressed_pages(struct compress_ctx *cc,
 	f2fs_put_rpages(cc);
 	page_array_free(cc->inode, cc->cpages, cc->nr_cpages);
 	cc->cpages = NULL;
-	f2fs_destroy_compress_ctx(cc);
+	f2fs_destroy_compress_ctx(cc, false);
 	return 0;
 
 out_destroy_crypt:
@@ -1461,7 +1462,7 @@ int f2fs_write_multi_pages(struct compress_ctx *cc,
 	err = f2fs_write_raw_pages(cc, submitted, wbc, io_type);
 	f2fs_put_rpages_wbc(cc, wbc, false, 0);
 destroy_out:
-	f2fs_destroy_compress_ctx(cc);
+	f2fs_destroy_compress_ctx(cc, false);
 	return err;
 }
 
diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 901bd1d963ee..bdc0f3b2d7ab 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -2419,7 +2419,7 @@ static int f2fs_mpage_readpages(struct inode *inode,
 							max_nr_pages,
 							&last_block_in_bio,
 							rac != NULL, false);
-				f2fs_destroy_compress_ctx(&cc);
+				f2fs_destroy_compress_ctx(&cc, false);
 				if (ret)
 					goto set_error_page;
 			}
@@ -2464,7 +2464,7 @@ static int f2fs_mpage_readpages(struct inode *inode,
 							max_nr_pages,
 							&last_block_in_bio,
 							rac != NULL, false);
-				f2fs_destroy_compress_ctx(&cc);
+				f2fs_destroy_compress_ctx(&cc, false);
 			}
 		}
 #endif
@@ -3168,7 +3168,7 @@ static int f2fs_write_cache_pages(struct address_space *mapping,
 		}
 	}
 	if (f2fs_compressed_file(inode))
-		f2fs_destroy_compress_ctx(&cc);
+		f2fs_destroy_compress_ctx(&cc, false);
 #endif
 	if (retry) {
 		index = 0;
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 036d2a3a2f41..69a390c6064c 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -3856,7 +3856,7 @@ void f2fs_free_dic(struct decompress_io_ctx *dic);
 void f2fs_decompress_end_io(struct page **rpages,
 			unsigned int cluster_size, bool err, bool verity);
 int f2fs_init_compress_ctx(struct compress_ctx *cc);
-void f2fs_destroy_compress_ctx(struct compress_ctx *cc);
+void f2fs_destroy_compress_ctx(struct compress_ctx *cc, bool reuse);
 void f2fs_init_compress_info(struct f2fs_sb_info *sbi);
 int f2fs_init_page_array_cache(struct f2fs_sb_info *sbi);
 void f2fs_destroy_page_array_cache(struct f2fs_sb_info *sbi);
-- 
2.30.2