On Wed, Nov 05, 2025 at 02:03:59PM +0100, Daniel Gomez wrote: > On 10/10/2025 05.06, Kees Cook wrote: > > v2: > > - use static_assert instead of _Static_assert > > - add Hans's Reviewed-by's > > v1: https://lore.kernel.org/lkml/[email protected]/ > > > > Hi! > > > > A long time ago we had an issue with embedded NUL bytes in MODULE_INFO > > strings[1]. While this stands out pretty strongly when you look at the > > code, and we can't do anything about a binary module that just plain lies, > > we never actually implemented the trivial compile-time check needed to > > detect it. > > > > Add this check (and fix 2 instances of needless trailing semicolons that > > this change exposed). > > > > Note that these patches were produced as part of another LLM exercise. > > This time I wanted to try "what happens if I ask an LLM to go read > > a specific LWN article and write a patch based on a discussion?" It > > pretty effortlessly chose and implemented a suggested solution, tested > > the change, and fixed new build warnings in the process. > > > > Since this was a relatively short session, here's an overview of the > > prompts involved as I guided it through a clean change and tried to see > > how it would reason about static_assert vs _Static_assert. (It wanted > > to use what was most common, not what was the current style -- we may > > want to update the comment above the static_assert macro to suggest > > using _Static_assert directly these days...) > > > > I want to fix a weakness in the module info strings. Read about it > > here: https://lwn.net/Articles/82305/ > > > > Since it's only "info" that we need to check, can you reduce the checks > > to just that instead of all the other stuff? > > > > I think the change to the comment is redundent, and that should be > > in a commit log instead. Let's just keep the change to the static assert. > > > > Is "static_assert" the idiomatic way to use a static assert in this > > code base? I've seen _Static_assert used sometimes. > > > > What's the difference between the two? > > > > Does Linux use C11 by default now? > > > > Then let's not use the wrapper any more. > > > > Do an "allmodconfig all -s" build to verify this works for all modules > > in the kernel. > > > > > > Thanks! > > > > -Kees > > > > [1] https://lwn.net/Articles/82305/ > > > > Kees Cook (3): > > media: dvb-usb-v2: lmedm04: Fix firmware macro definitions > > media: radio: si470x: Fix DRIVER_AUTHOR macro definition > > module: Add compile-time check for embedded NUL characters > > > > include/linux/moduleparam.h | 3 +++ > > drivers/media/radio/si470x/radio-si470x-i2c.c | 2 +- > > drivers/media/usb/dvb-usb-v2/lmedm04.c | 12 ++++++------ > > 3 files changed, 10 insertions(+), 7 deletions(-) > > > > Reviewed-by: Daniel Gomez <[email protected]> > > I have also tested a build of v6.18-rc3 + patches using allmodconfig: > > Tested-by: Daniel Gomez <[email protected]>
Folks, are you aware that this change blown up the sparse? Now there is a "bad constant expression" to each MODULE_*() macro line. Nice that Uwe is in the Cc list, so IIRC he is Debian maintainer for sparse and perhaps has an influence to it to some extent. -- With Best Regards, Andy Shevchenko
