[PATCH AUTOSEL 6.0 26/32] f2fs: fix to detect corrupted meta ino

Sasha Levin
2022-10-18T00:11:35Z

From: Chao Yu <chao@kernel.org>

[ Upstream commit fcc2d8cc96b2f6141bbbe5b1e8953db990794b44 ]

It is possible that ino of dirent or orphan inode is corrupted in a
fuzzed image, occasionally, if corrupted ino is equal to meta ino:
meta_ino, node_ino or compress_ino, caller of f2fs_iget() from below
call paths will get meta inode directly, it's not allowed, let's
add sanity check to detect such cases.

case #1
- recover_dentry
- __f2fs_find_entry
- f2fs_iget_retry

case #2
- recover_orphan_inode
- f2fs_iget_retry

Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
fs/f2fs/inode.c | 21 ++++++++++++++++-----
1 file changed, 16 insertions(+), 5 deletions(-)

diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c
index 6d11c365d7b4..34324ef48667 100644
--- a/fs/f2fs/inode.c
+++ b/fs/f2fs/inode.c
@@ -480,6 +480,12 @@ static int do_read_inode(struct inode *inode)
return 0;
}

+static bool is_meta_ino(struct f2fs_sb_info *sbi, unsigned int ino)
+{
+ return ino == F2FS_NODE_INO(sbi) || ino == F2FS_META_INO(sbi) ||
+ ino == F2FS_COMPRESS_INO(sbi);
+}
+
struct inode *f2fs_iget(struct super_block *sb, unsigned long ino)
{
struct f2fs_sb_info *sbi = F2FS_SB(sb);
@@ -491,16 +497,21 @@ struct inode *f2fs_iget(struct super_block *sb, unsigned long ino)
return ERR_PTR(-ENOMEM);

if (!(inode->i_state & I_NEW)) {
+ if (is_meta_ino(sbi, ino)) {
+ f2fs_err(sbi, "inaccessible inode: %lu, run fsck to repair", ino);
+ set_sbi_flag(sbi, SBI_NEED_FSCK);
+ ret = -EFSCORRUPTED;
+ trace_f2fs_iget_exit(inode, ret);
+ iput(inode);
+ return ERR_PTR(ret);
+ }
+
trace_f2fs_iget(inode);
return inode;
}
- if (ino == F2FS_NODE_INO(sbi) || ino == F2FS_META_INO(sbi))
- goto make_now;

-#ifdef CONFIG_F2FS_FS_COMPRESSION
- if (ino == F2FS_COMPRESS_INO(sbi))
+ if (is_meta_ino(sbi, ino))
goto make_now;
-#endif

ret = do_read_inode(inode);
if (ret)
--
2.35.1