[JFFS2] Don't trust node headers before the CRC is checked.

Especially when summary code is used, we can have in-memory data
structures referencing certain nodes without them actually being readable
on the flash. Discard the nodes gracefully in that case, rather than
triggering a BUG().

Signed-off-by: David Woodhouse <dwmw2@infradead.org>
1 file changed