Re: [PATCH] isofs: bound empty directory blocks in isofs_read_level3_size()

[Matthias Goergens <matthias.goergens@gmail.com>]

Hi Honza,

> Right, that needs a bit more care but still, something like the attached
> patch should work?

Yes, it does.  Testing the next-section link as "not yet set" instead
of "i == 1" is what was missing from the first variant.  I ran your
patch on top of v1, built in userspace with ASan and UBSan, against 67
test images: empty blocks between and after the section records,
three-section files, and the 100 bound from both sides.  i_size, the
recorded next section, the limit message and the file contents match
v1 on every image, including the split-gap one your first variant read
wrongly.  No sanitizer reports.

Reviewed-by: Matthias Goergens <matthias.goergens@gmail.com>
Tested-by: Matthias Goergens <matthias.goergens@gmail.com>

Thanks,
Matthias