f2fs: fix race conditon on truncation with inline_data
Let's consider the following scenario.
blkaddr[0] inline_data i_size i_blocks writepage truncate
NEW X 4096 2 dirty page #0
NEW X 0 change i_size
NEW X 0 2 f2fs_write_inline_data
NEW X 0 2 get_dnode_of_data
NEW X 0 2 truncate_data_blocks_range
NULL O 0 1 memcpy(inline_data)
NULL O 0 1 f2fs_put_dnode
NULL O 0 1 f2fs_truncate
NULL O 0 1 get_dnode_of_data
NULL O 0 1 *invalid block addr*
This patch adds checking inline_data flag during f2fs_truncate not to refer
corrupted block indices.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index 8e68bb6..543d8c6 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -473,6 +473,12 @@
return err;
}
+ /* writepage can convert inline_data under get_donde_of_data */
+ if (f2fs_has_inline_data(inode)) {
+ f2fs_put_dnode(&dn);
+ goto done;
+ }
+
count = ADDRS_PER_PAGE(dn.node_page, F2FS_I(inode));
count -= dn.ofs_in_node;