[PATCH] cpukit/jffs2: Handle used empty file system

[Sebastian Huber]

Hello Kinsey,

On 02.02.24 23:03, Kinsey Moore wrote:
> On JFFS2 file systems on NOR flash or dataflash that does not have spare
> area for metadata and thus does not invoke delayed writes, it is
> possible to put the file system into a state where all blocks have been
> written to and all files have been deleted from the filesystem. There is
> a bug in the JFFS2 file system scan routine that detects this situation
> as a corrupted file system since the scan routine relies on "used" space
> to discriminate a valid file system when there are blocks that need to
> be erased. The correct fix would require a partial rewrite of the scan
> routine, so instead this patch tracks the space marked as obsolete along
> with space at the end of each block that is otherwise too small to
> contain a JFFS2 node so that it can me compared with the dirty space.
> Corrupted data (or otherwise non-JFFS2 blocks) will still cause this
> check to fail as corrupted data isn't recognized as obsoleted (deleted)
> nodes.

this should be reported to the Linux JFFS2 maintainers. A test case 
would be also nice.

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