diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 4ce35f1c8b0a..d7732320431a 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -789,10 +789,22 @@ int ext4_get_block(struct inode *inode, sector_t iblock, int ext4_get_block_unwritten(struct inode *inode, sector_t iblock, struct buffer_head *bh_result, int create) { + int ret = 0; + ext4_debug("ext4_get_block_unwritten: inode %lu, create flag %d\n", inode->i_ino, create); - return _ext4_get_block(inode, iblock, bh_result, + ret = _ext4_get_block(inode, iblock, bh_result, EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT); + + /* + * If the buffer is marked unwritten, mark it as new to make sure it is + * zeroed out correctly in case of partial writes. Otherwise, there is + * a chance of stale data getting exposed. + */ + if (ret == 0 && buffer_unwritten(bh_result)) + set_buffer_new(bh_result); + + return ret; } /* Maximum number of blocks we map for direct IO at once. */