From 6dc2b804a042d2ff0fdf4c8e3db78669c36b688d Mon Sep 17 00:00:00 2001 From: Wenjie Qi Date: Mon, 3 Aug 2026 19:41:53 +0800 Subject: f2fs: reject invalid recovered filename lengths Recovery uses raw_inode->i_namelen directly when rebuilding fsynced dentries. A zero-length name uses no dentry slots, so recovery can report success without recreating the dentry. Treat zero-length and oversized recovered names as corruption, mark NEED_FSCK, and stop recovery with -EFSCORRUPTED. Signed-off-by: Wenjie Qi Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim --- fs/f2fs/recovery.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) diff --git a/fs/f2fs/recovery.c b/fs/f2fs/recovery.c index 3fecfdbd5958..aaa5227739c8 100644 --- a/fs/f2fs/recovery.c +++ b/fs/f2fs/recovery.c @@ -116,18 +116,26 @@ static void del_fsync_inode(struct fsync_inode_entry *entry, int drop) } static int init_recovered_filename(const struct inode *dir, + struct inode *inode, struct f2fs_inode *raw_inode, struct f2fs_filename *fname, struct qstr *usr_fname) { + struct f2fs_sb_info *sbi = F2FS_I_SB(inode); int err; memset(fname, 0, sizeof(*fname)); fname->disk_name.len = le32_to_cpu(raw_inode->i_namelen); fname->disk_name.name = raw_inode->i_name; - if (WARN_ON(fname->disk_name.len > F2FS_NAME_LEN)) - return -ENAMETOOLONG; + if (unlikely(!fname->disk_name.len || + fname->disk_name.len > F2FS_NAME_LEN)) { + f2fs_err(sbi, "invalid recovered filename length %u for ino %llu", + fname->disk_name.len, inode->i_ino); + set_sbi_flag(sbi, SBI_NEED_FSCK); + f2fs_handle_error(sbi, ERROR_CORRUPTED_INODE); + return -EFSCORRUPTED; + } if (!IS_ENCRYPTED(dir)) { usr_fname->name = fname->disk_name.name; @@ -201,7 +209,7 @@ static int recover_dentry(struct inode *inode, struct folio *ifolio, } dir = entry->inode; - err = init_recovered_filename(dir, raw_inode, &fname, &usr_fname); + err = init_recovered_filename(dir, inode, raw_inode, &fname, &usr_fname); if (err) goto out; retry: -- cgit v1.2.3