f2fs: avoid wrong decrypted data from disk

1. Create a file in an encrypted directory
2. Do GC & drop caches
3. Read stale data before its bio for metapage was not issued yet

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 382c1ef..8c204f8 100644 (file)
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -565,9 +565,6 @@ static struct bio *f2fs_grab_read_bio(struct inode *inode, block_t blkaddr,
                ctx->bio = bio;
                ctx->enabled_steps = post_read_steps;
                bio->bi_private = ctx;
-
-               /* wait the page to be moved by cleaning */
-               f2fs_wait_on_block_writeback(sbi, blkaddr);
        }
 
        return bio;
@@ -582,6 +579,9 @@ static int f2fs_submit_page_read(struct inode *inode, struct page *page,
        if (IS_ERR(bio))
                return PTR_ERR(bio);
 
+       /* wait for GCed page writeback via META_MAPPING */
+       f2fs_wait_on_block_writeback(inode, blkaddr);
+
        if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE) {
                bio_put(bio);
                return -EFAULT;
@@ -1558,6 +1558,12 @@ submit_and_realloc:
                        }
                }
 
+               /*
+                * If the page is under writeback, we need to wait for
+                * its completion to see the correct decrypted data.
+                */
+               f2fs_wait_on_block_writeback(inode, block_nr);
+
                if (bio_add_page(bio, page, blocksize, 0) < blocksize)
                        goto submit_and_realloc;
 
@@ -1625,7 +1631,7 @@ static int encrypt_one_page(struct f2fs_io_info *fio)
                return 0;
 
        /* wait for GCed page writeback via META_MAPPING */
-       f2fs_wait_on_block_writeback(fio->sbi, fio->old_blkaddr);
+       f2fs_wait_on_block_writeback(inode, fio->old_blkaddr);
 
 retry_encrypt:
        fio->encrypted_page = fscrypt_encrypt_page(inode, fio->page,
@@ -2382,10 +2388,6 @@ repeat:
 
        f2fs_wait_on_page_writeback(page, DATA, false);
 
-       /* wait for GCed page writeback via META_MAPPING */
-       if (f2fs_post_read_required(inode))
-               f2fs_wait_on_block_writeback(sbi, blkaddr);
-
        if (len == PAGE_SIZE || PageUptodate(page))
                return 0;
 

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index b3de6c5..ad26ee0 100644 (file)
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -2942,7 +2942,7 @@ void f2fs_allocate_data_block(struct f2fs_sb_info *sbi, struct page *page,
                        struct f2fs_io_info *fio, bool add_list);
 void f2fs_wait_on_page_writeback(struct page *page,
                        enum page_type type, bool ordered);
-void f2fs_wait_on_block_writeback(struct f2fs_sb_info *sbi, block_t blkaddr);
+void f2fs_wait_on_block_writeback(struct inode *inode, block_t blkaddr);
 void f2fs_write_data_summaries(struct f2fs_sb_info *sbi, block_t start_blk);
 void f2fs_write_node_summaries(struct f2fs_sb_info *sbi, block_t start_blk);
 int f2fs_lookup_journal_in_cursum(struct f2fs_journal *journal, int type,

diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index ca66b3e..e21a192 100644 (file)
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -112,8 +112,7 @@ mapped:
        f2fs_wait_on_page_writeback(page, DATA, false);
 
        /* wait for GCed page writeback via META_MAPPING */
-       if (f2fs_post_read_required(inode))
-               f2fs_wait_on_block_writeback(sbi, dn.data_blkaddr);
+       f2fs_wait_on_block_writeback(inode, dn.data_blkaddr);
 
 out_sem:
        up_read(&F2FS_I(inode)->i_mmap_sem);

diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index 34e0577..187c848 100644 (file)
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -3195,10 +3195,14 @@ void f2fs_wait_on_page_writeback(struct page *page,
        }
 }
 
-void f2fs_wait_on_block_writeback(struct f2fs_sb_info *sbi, block_t blkaddr)
+void f2fs_wait_on_block_writeback(struct inode *inode, block_t blkaddr)
 {
+       struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
        struct page *cpage;
 
+       if (!f2fs_post_read_required(inode))
+               return;
+
        if (!is_valid_data_blkaddr(sbi, blkaddr))
                return;