From 84e21e3fb8fd99ea460eb7274584750d11cf3e9f Mon Sep 17 00:00:00 2001 From: Zhang Yi Date: Sat, 31 Jan 2026 17:11:56 +0800 Subject: [PATCH] ext4: do not check fast symlink during orphan recovery Commit '5f920d5d6083 ("ext4: verify fast symlink length")' causes the generic/475 test to fail during orphan cleanup of zero-length symlinks. generic/475 84s ... _check_generic_filesystem: filesystem on /dev/vde is inconsistent The fsck reports are provided below: Deleted inode 9686 has zero dtime. Deleted inode 158230 has zero dtime. ... Inode bitmap differences: -9686 -158230 Orphan file (inode 12) block 13 is not clean. Failed to initialize orphan file. In ext4_symlink(), a newly created symlink can be added to the orphan list due to ENOSPC. Its data has not been initialized, and its size is zero. Therefore, we need to disregard the length check of the symbolic link when cleaning up orphan inodes. Instead, we should ensure that the nlink count is zero. Fixes: 5f920d5d6083 ("ext4: verify fast symlink length") Signed-off-by: Zhang Yi Reviewed-by: Jan Kara Link: https://patch.msgid.link/20260131091156.1733648-1-yi.zhang@huaweicloud.com Signed-off-by: Theodore Ts'o Cc: stable@kernel.org --- fs/ext4/inode.c | 40 +++++++++++++++++++++++++++++----------- 1 file changed, 29 insertions(+), 11 deletions(-) diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 396dc3a5d16b..af6d1759c8de 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -5401,18 +5401,36 @@ struct inode *__ext4_iget(struct super_block *sb, unsigned long ino, inode->i_op = &ext4_encrypted_symlink_inode_operations; } else if (ext4_inode_is_fast_symlink(inode)) { inode->i_op = &ext4_fast_symlink_inode_operations; - if (inode->i_size == 0 || - inode->i_size >= sizeof(ei->i_data) || - strnlen((char *)ei->i_data, inode->i_size + 1) != - inode->i_size) { - ext4_error_inode(inode, function, line, 0, - "invalid fast symlink length %llu", - (unsigned long long)inode->i_size); - ret = -EFSCORRUPTED; - goto bad_inode; + + /* + * Orphan cleanup can see inodes with i_size == 0 + * and i_data uninitialized. Skip size checks in + * that case. This is safe because the first thing + * ext4_evict_inode() does for fast symlinks is + * clearing of i_data and i_size. + */ + if ((EXT4_SB(sb)->s_mount_state & EXT4_ORPHAN_FS)) { + if (inode->i_nlink != 0) { + ext4_error_inode(inode, function, line, 0, + "invalid orphan symlink nlink %d", + inode->i_nlink); + ret = -EFSCORRUPTED; + goto bad_inode; + } + } else { + if (inode->i_size == 0 || + inode->i_size >= sizeof(ei->i_data) || + strnlen((char *)ei->i_data, inode->i_size + 1) != + inode->i_size) { + ext4_error_inode(inode, function, line, 0, + "invalid fast symlink length %llu", + (unsigned long long)inode->i_size); + ret = -EFSCORRUPTED; + goto bad_inode; + } + inode_set_cached_link(inode, (char *)ei->i_data, + inode->i_size); } - inode_set_cached_link(inode, (char *)ei->i_data, - inode->i_size); } else { inode->i_op = &ext4_symlink_inode_operations; }