Re: [PATCH 1/5] module: Fix module_sig_check() for modules with ignored modversions/vermagic

On Fri, Aug 22, 2025 at 5:55 AM Jinchao Wang [off-list ref] wrote:

The current signature check logic incorrectly fails modules that have
valid signatures when the caller specifies MODULE_INIT_IGNORE_MODVERSIONS
or MODULE_INIT_IGNORE_VERMAGIC flags. This happens because the code
treats these flags as indicating a "mangled module" and skips signature
verification entirely.

The key insight is that the intent of the caller (to ignore modversions
or vermagic) should not affect signature verification. A module with
a valid signature should be verified regardless of whether the caller
wants to ignore versioning information.

Why would you need to ignore versions when loading signed modules?
Here's the original series that added this check and I feel it's very
much relevant still:

https://lore.kernel.org/lkml/20160423184421.GL3348@decadent.org.uk/ (local)

Sami