[PATCH 00/12] module: cleanup and call taints after is inserted

From: Luis Chamberlain
Date: Sun Mar 19 2023 - 17:28:06 EST


After posting my first RFC for "module: avoid userspace pressure on unwanted
allocations" [0] I ended up doing much more cleanup on the module loading path.
One of the things that became evident while ensuring we do *less* work before
kmalloc all the things we need for the final module is we are doing a lot of
work before we even add a module onto our linked list, once its accepted for
loading and running init. We even *taint* the kernel even before we accept
a module. We also do some tainting after kernel loading.

This converges both to one point -- right as soon as we accept module
into our linked list. That is, the module is valid as per our kernel
config and we're ready to go. Most of this is just tidying code up. The
biggest functional changes is under the patch "converge taint work together".

I'll post the other functional changes in two other patch sets. This is
mostly cleanup, the next one is the new ELF checks / sanity / cleanup,
and I'm waiting to hear back from David Hildenbrand on the worthiness of
some clutches for allocation. That last part would go in the last patch
series.

In this series I've dropped completely the idea of using aliasing since
different modules can share the same alias, so using that to check if
a module is already loaded turns out not to be useful in any way.

[0] https://lkml.kernel.org/r/20230311051712.4095040-1-mcgrof@xxxxxxxxxx

Luis Chamberlain (12):
module: move get_modinfo() helpers all above
module: rename next_string() to module_next_tag_pair()
module: add a for_each_modinfo_entry()
module: move early sanity checks into a helper
module: move check_modinfo() early to early_mod_check()
module: rename set_license() to module_license_taint_check()
module: split taint work out of check_modinfo_livepatch()
module: split taint adding with info checking
module: move tainting until after a module hits our linked list
module: move signature taint to module_augment_kernel_taints()
module: converge taint work together
module: rename check_module_license_and_versions() to
check_export_symbol_versions()

kernel/module/internal.h | 5 +
kernel/module/main.c | 292 ++++++++++++++++++++-------------------
2 files changed, 158 insertions(+), 139 deletions(-)

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2.39.1