corruption of JFFS2 filesystem, csize is set to 0 after moving a block

[David Woodhouse]

On Fri, 2007-04-27 at 11:13 +0200, Hans-Christian Egtvedt wrote:
> 
> Some filesystem dump from before:
>          Dirent     node at 0x0013c7e0, totlen 0x0000003b, #pino     7, version   148, #ino       150, nsize       19, name ld-uClibc-0.9.28.so
>          Inode      node at 0x0013c81c, totlen 0x00000a14, #ino    150, version     1, isize    13108, csize     2512, dsize     4092, offset        0
>          Inode      node at 0x0013d230, totlen 0x00000c57, #ino    150, version     2, isize    13108, csize     3091, dsize     4092, offset     4092
>          Inode      node at 0x0013de88, totlen 0x00000b21, #ino    150, version     3, isize    13108, csize     2781, dsize     4092, offset     8184
>          Inode      node at 0x0013e9ac, totlen 0x000001e0, #ino    150, version     4, isize    13108, csize      412, dsize      832, offset    12276

Those are suspect. Why 4092 bytes not 4096? The node with version 2
claims to be 4092 bytes starting from 4092, which is invalid because it
crosses a page boundary.

> After:
>          Dirent     node at 0x006c7bf0, totlen 0x0000003b, #pino     7, version   171, #ino       150, nsize       19, name ld-uClibc-0.9.28.so
>          Inode      node at 0x006c7c2c, totlen 0x00000a14, #ino    150, version     5, isize    13108, csize     2512, dsize     4092, offset        0
>          Inode      node at 0x006c8640, totlen 0x00000044, #ino    150, version     6, isize    13108, csize        0, dsize     4092, offset     4092
>          Inode      node at 0x006c8684, totlen 0x00000044, #ino    150, version     7, isize    13108, csize        0, dsize     4092, offset     8184
>          Inode      node at 0x006c86c8, totlen 0x00000044, #ino    150, version     8, isize    13108, csize        0, dsize      832, offset    12276 

Ok, in that case I agree that a csize of zero also looks suspicious.
Matches the node 'totlen' though. What's the compression type.

Did you use 'mkfs.jffs2 -s 4092'?

-- 
dwmw2