Re: [PATCH 4.19 29/71] btrfs: tree-checker: Verify inode item

From: Qu Wenruo
Date: Wed Nov 11 2020 - 08:39:12 EST




On 2020/11/11 下午9:13, Pavel Machek wrote:
> Hi!
>
>> From: Qu Wenruo <wqu@xxxxxxxx>
>>
>> commit 496245cac57e26d8b738d85c7a29cf9a47610f3f upstream.
>>
>> There is a report in kernel bugzilla about mismatch file type in dir
>> item and inode item.
>>
>> This inspires us to check inode mode in inode item.
>>
>> This patch will check the following members:
>
>> + /* Here we use super block generation + 1 to handle log tree */
>> + if (btrfs_inode_generation(leaf, iitem) > super_gen + 1) {
>> + inode_item_err(fs_info, leaf, slot,
>> + "invalid inode generation: has %llu expect (0, %llu]",
>> + btrfs_inode_generation(leaf, iitem),
>> + super_gen + 1);
>> + return -EUCLEAN;
>> + }
>
> Printk suggests btrfs_inode_generation() may not be zero, but the
> condition does not actually check that. Should that be added?

Sorry, btrfs_inode_generation() here is exactly what we're checking
here, so what's wrong?

Or did you mean the next chunk of btrfs_inode_transid() check?

That error message is wrong, and we had upstream fix for it:
f96d6960abbc ("btrfs: tree-checker: fix the error message for transid
error")

Thanks,
Qu

>
>> + /* Note for ROOT_TREE_DIR_ITEM, mkfs could set its transid 0 */
>> + if (btrfs_inode_transid(leaf, iitem) > super_gen + 1) {
>> + inode_item_err(fs_info, leaf, slot,
>> + "invalid inode generation: has %llu expect [0, %llu]",
>> + btrfs_inode_transid(leaf, iitem), super_gen + 1);
>> + return -EUCLEAN;
>> + }
>
> Best regards,
> Pavel
>