[PATCH 2/2] f2fs: fix to do sanity check on blocks for inline_data inode

[Chao Yu]

inode can be fuzzed, so it can has F2FS_INLINE_DATA flag and valid
i_blocks/i_nid value, this patch supports to do extra sanity check
to detect such corrupted state.

Signed-off-by: Chao Yu <chao@xxxxxxxxxx>
---
 fs/f2fs/f2fs.h   |  2 +-
 fs/f2fs/inline.c | 20 +++++++++++++++++++-
 fs/f2fs/inode.c  |  2 +-
 3 files changed, 21 insertions(+), 3 deletions(-)

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 1974b6aff397..f463961b497c 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -4149,7 +4149,7 @@ extern struct kmem_cache *f2fs_inode_entry_slab;
  * inline.c
  */
 bool f2fs_may_inline_data(struct inode *inode);
-bool f2fs_sanity_check_inline_data(struct inode *inode);
+bool f2fs_sanity_check_inline_data(struct inode *inode, struct page *ipage);
 bool f2fs_may_inline_dentry(struct inode *inode);
 void f2fs_do_read_inline_data(struct folio *folio, struct page *ipage);
 void f2fs_truncate_inline_inode(struct inode *inode,
diff --git a/fs/f2fs/inline.c b/fs/f2fs/inline.c
index 7638d0d7b7ee..0203c3baabb6 100644
--- a/fs/f2fs/inline.c
+++ b/fs/f2fs/inline.c
@@ -33,11 +33,29 @@ bool f2fs_may_inline_data(struct inode *inode)
 	return !f2fs_post_read_required(inode);
 }
 
-bool f2fs_sanity_check_inline_data(struct inode *inode)
+static bool inode_has_blocks(struct inode *inode, struct page *ipage)
+{
+	struct f2fs_inode *ri = F2FS_INODE(ipage);
+	int i;
+
+	if (F2FS_HAS_BLOCKS(inode))
+		return true;
+
+	for (i = 0; i < DEF_NIDS_PER_INODE; i++) {
+		if (ri->i_nid[i])
+			return true;
+	}
+	return false;
+}
+
+bool f2fs_sanity_check_inline_data(struct inode *inode, struct page *ipage)
 {
 	if (!f2fs_has_inline_data(inode))
 		return false;
 
+	if (inode_has_blocks(inode, ipage))
+		return false;
+
 	if (!support_inline_data(inode))
 		return true;
 
diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c
index 791c06e159fd..4b39aebd3c70 100644
--- a/fs/f2fs/inode.c
+++ b/fs/f2fs/inode.c
@@ -344,7 +344,7 @@ static bool sanity_check_inode(struct inode *inode, struct page *node_page)
 		}
 	}
 
-	if (f2fs_sanity_check_inline_data(inode)) {
+	if (f2fs_sanity_check_inline_data(inode, node_page)) {
 		f2fs_warn(sbi, "%s: inode (ino=%lx, mode=%u) should not have inline_data, run fsck to fix",
 			  __func__, inode->i_ino, inode->i_mode);
 		return false;
-- 
2.40.1