Re: [PATCH] ext4: fix the time handling macros when ext4 is using small inodes

From: Jan Kara
Date: Wed Aug 02 2023 - 06:38:41 EST

On Tue 18-07-23 13:31:59, Jeff Layton wrote:
> If ext4 is using small on-disk inodes, then it may not be able to store
> fine grained timestamps. It also can't store the i_crtime at all in that
> case since that fully lives in the extended part of the inode.
> 979492850abd got the EXT4_EINODE_{GET,SET}_XTIME macros wrong, and would
> still store the tv_sec field of the i_crtime into the raw_inode, even
> when they were small, corrupting adjacent memory.
> This fixes those macros to skip setting anything in the raw_inode if the
> tv_sec field doesn't fit, and to properly return a {0,0} timestamp when
> the raw_inode doesn't support it.
> Cc: Jan Kara <jack@xxxxxxx>
> Fixes: 979492850abd ("ext4: convert to ctime accessor functions")
> Reported-by: Hugh Dickins <hughd@xxxxxxxxxx>
> Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx>

I've seen Christian has already folded this fixup so I just want to say:
Thanks for fixing this up while I was away!

Jan Kara <jack@xxxxxxxx>