[PATCH] f2fs: fix to do sanity check on nat entry of quota inode

From: Chao Yu

Date: Thu Dec 18 2025 - 21:51:14 EST


As Zhiguo reported, nat entry of quota inode could be corrupted:

"ino/block_addr=NULL_ADDR in nid=4 entry"

We'd better to do sanity check on quota inode to detect and record
nat.blk_addr inconsistency, so that we can have a chance to repair
it w/ later fsck.

Reported-by: Zhiguo Niu <zhiguo.niu@xxxxxxxxxx>
Signed-off-by: Chao Yu <chao@xxxxxxxxxx>
---
fs/f2fs/f2fs.h | 6 +++---
fs/f2fs/inode.c | 2 +-
fs/f2fs/node.c | 11 +++++++++++
3 files changed, 15 insertions(+), 4 deletions(-)

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 65ca1a5eaa88..c458df92bb0d 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -4928,16 +4928,16 @@ static inline bool is_journalled_quota(struct f2fs_sb_info *sbi)
return false;
}

-static inline bool f2fs_quota_file(struct inode *inode)
+static inline bool f2fs_quota_file(struct f2fs_sb_info *sbi, nid_t ino)
{
#ifdef CONFIG_QUOTA
int i;

- if (!f2fs_sb_has_quota_ino(F2FS_I_SB(inode)))
+ if (!f2fs_sb_has_quota_ino(sbi))
return false;

for (i = 0; i < MAXQUOTAS; i++) {
- if (f2fs_qf_ino(F2FS_I_SB(inode)->sb, i) == inode->i_ino)
+ if (f2fs_qf_ino(sbi->sb, i) == ino)
return true;
}
#endif
diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c
index 921fb02c0f49..d1270b25ad7d 100644
--- a/fs/f2fs/inode.c
+++ b/fs/f2fs/inode.c
@@ -621,7 +621,7 @@ struct inode *f2fs_iget(struct super_block *sb, unsigned long ino)
inode->i_fop = &f2fs_file_operations;
inode->i_mapping->a_ops = &f2fs_dblock_aops;
if (IS_IMMUTABLE(inode) && !f2fs_compressed_file(inode) &&
- !f2fs_quota_file(inode))
+ !f2fs_quota_file(sbi, inode->i_ino))
mapping_set_folio_min_order(inode->i_mapping, 0);
} else if (S_ISDIR(inode->i_mode)) {
inode->i_op = &f2fs_dir_inode_operations;
diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
index 7feead595ba5..f1e6fa2dccc9 100644
--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -643,6 +643,17 @@ int f2fs_get_node_info(struct f2fs_sb_info *sbi, nid_t nid,
return -EFSCORRUPTED;
}

+ if (unlikely(f2fs_quota_file(sbi, ni->nid) &&
+ !__is_valid_data_blkaddr(ni->blk_addr))) {
+ set_sbi_flag(sbi, SBI_NEED_FSCK);
+ f2fs_err_ratelimited(sbi,
+ "f2fs_get_node_info of %pS: inconsistent nat entry from qf_ino, "
+ "ino:%u, nid:%u, blkaddr:%u, ver:%u, flag:%u",
+ __builtin_return_address(0),
+ ni->ino, ni->nid, ni->blk_addr, ni->version, ni->flag);
+ f2fs_handle_error(sbi, ERROR_INCONSISTENT_NAT);
+ }
+
/* cache nat entry */
if (need_cache)
cache_nat_entry(sbi, nid, &ne);
--
2.40.1