tree 30ac39aabb953090fe3552ba341eaa68cf9bf746
parent 185b0bcdef4bda061230a26b2e29ae18663ca819
author Hu Weiwen <sehuww@mail.scut.edu.cn> 1613318404 +0800
committer Gao Xiang <hsiangkao@aol.com> 1614011574 +0800

erofs-utils: fix battach on full buffer blocks

When the subsequent erofs_battach() is called on an buffer block of
which (bb->buffers.off % EROFS_BLKSIZ == 0), `tail_blkaddr' won't be
updated correctly. This bug can be reproduced by:

mkdir bug-repo
head -c 4032 /dev/urandom > bug-repo/1
head -c 4095 /dev/urandom > bug-repo/2
head -c 12345 /dev/urandom > bug-repo/3  # arbitrary size
mkfs.erofs -Eforce-inode-compact bug-repo.erofs.img bug-repo
Then mount this image and see that file `3' in the image is different
from `bug-repo/3'.

This patch fix this by:
 * Handle `oob' and `tail_blkaddr' for the case above properly;
 * Don't inline tail-packing data for such case, since the tail-packing
   data is actually in a different block from inode itself even kernel
   can handle such cases properly.

Link: https://lore.kernel.org/r/20210214160004.6075-1-hsiangkao@aol.com
Signed-off-by: Hu Weiwen <sehuww@mail.scut.edu.cn>
Reviewed-by: Gao Xiang <hsiangkao@aol.com>
Reviewed-by: Li Guifu <bluce.lee@aliyun.com>
Signed-off-by: Gao Xiang <hsiangkao@aol.com>