Offering: HULK hulk inclusion category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I9DN5Z -------------------------------- Since commit 7f6416dcd4a3f ("ext4: implement writeback iomap path"), the order mode is removed in iomap framework, which lets ext4_mb_clear_bb() free data blocks immediately. It may cause stale data read from truncated file in power-cut case. Following is details: P1 P2 vfs_truncate(file A) ext4_setattr EXT4_I(inode)->i_disksize = attr->ia_size // record in journal ext4_truncate ext4_mb_clear_bb mb_free_blocks // free block i vfs_write(file B) // get block i and writeback >> powercut << In the next mount, inode size and extent tree is stale(before truncated), the content in block i is file B. Fix the problem by tracking free data blocks in journal for iomap/non-writeback case. Fixes: 7f6416dcd4a3 ("ext4: implement writeback iomap path") Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com> --- fs/ext4/ext4_jbd2.c | 9 ++------- fs/ext4/ext4_jbd2.h | 7 +++++++ 2 files changed, 9 insertions(+), 7 deletions(-) diff --git a/fs/ext4/ext4_jbd2.c b/fs/ext4/ext4_jbd2.c index 94c8073b49e7..cac0eb5068d3 100644 --- a/fs/ext4/ext4_jbd2.c +++ b/fs/ext4/ext4_jbd2.c @@ -11,18 +11,13 @@ int ext4_inode_journal_mode(struct inode *inode) { if (EXT4_JOURNAL(inode) == NULL) return EXT4_INODE_WRITEBACK_DATA_MODE; /* writeback */ - /* - * Ordered mode is no longer needed for the inode that use the - * iomap path, always use writeback mode. - */ - if (ext4_test_inode_state(inode, EXT4_STATE_BUFFERED_IOMAP)) - return EXT4_INODE_WRITEBACK_DATA_MODE; /* writeback */ /* We do not support data journalling with delayed allocation */ if (!S_ISREG(inode->i_mode) || ext4_test_inode_flag(inode, EXT4_INODE_EA_INODE) || test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA || (ext4_test_inode_flag(inode, EXT4_INODE_JOURNAL_DATA) && - !test_opt(inode->i_sb, DELALLOC))) { + !test_opt(inode->i_sb, DELALLOC) && + !ext4_test_inode_state(inode, EXT4_STATE_BUFFERED_IOMAP))) { /* We do not support data journalling for encrypted data */ if (S_ISREG(inode->i_mode) && IS_ENCRYPTED(inode)) return EXT4_INODE_ORDERED_DATA_MODE; /* ordered */ diff --git a/fs/ext4/ext4_jbd2.h b/fs/ext4/ext4_jbd2.h index 0c77697d5e90..c52d1caf6622 100644 --- a/fs/ext4/ext4_jbd2.h +++ b/fs/ext4/ext4_jbd2.h @@ -467,6 +467,13 @@ static inline int ext4_should_journal_data(struct inode *inode) static inline int ext4_should_order_data(struct inode *inode) { + /* + * Ordered mode is no longer needed for the inode that use the + * iomap path, always use writeback mode. + */ + if (ext4_test_inode_state(inode, EXT4_STATE_BUFFERED_IOMAP)) + return 0; /* writeback */ + return ext4_inode_journal_mode(inode) & EXT4_INODE_ORDERED_DATA_MODE; } -- 2.31.1