linux-ext4 - Re: A question on directory checksums

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Message-ID: <alpine.DEB.2.21.2002231833120.135389@stalin.acc.umu.se>
Date:   Sun, 23 Feb 2020 18:40:21 +0100 (CET)
From:   Bo Branten <bosse@....umu.se>
To:     linux-ext4@...r.kernel.org
Subject: Re: A question on directory checksums

On Sat, 22 Feb 2020, Bo Branten wrote:

> /dev/sdb2: Directory inode 64, block #0, offset 0: directory has no checksum.

I think I should tell you how I solved this: It was a good advice to use 
debugfs, with it I could dump the directory block before and after running 
e2fsck and then I found out that it was rec_len in the last directory 
entry in a block that we did not initialize correctly, before it should 
extend to the end of the block but with cecksums we should subtract 
sizeof(struct ext4_dir_entry_tail) from it, thats why e2fsck did not look 
at the checksum even if it was there.

Thank you for youre help.

Bo Branten