On Fri, Aug 28, 2026 at 5:53 AM Petr Mladek <[email protected]> wrote: > > When a module is loaded, klp_module_coming() iterates over patches and > calls klp_init_object_loaded(). If initialization fails, it delegates > cleanup to klp_cleanup_module_patches_limited(). > > However, the cleanup loop skips the failing patch. Each function called > in klp_init_object_loaded() is supposed to clean its own changes. This > works except for the changes done by klp_init_object_loaded(). > > The current code is a bit messy. The changes done by > klp_init_object_loaded() should get cleared by klp_free_object_loaded(). > But this function also clears obj->mod which is set by > klp_module_coming(). And relocations are cleared separately. > > Fix the situations by updating klp_free_object_loaded(). It should > revert all and only changes made by klp_init_object_loaded(). > This requires some shuffling: > > + Clear obj->mod explicitly in klp_cleanup_module_patches_limited() > and do not rely on klp_free_object_loaded(). > > + Clear relocations in klp_free_object_loaded(). Remove the explicit > call from klp_cleanup_module_patches_limited(). This requires > adding the @patch parameter. > > Finally, call klp_free_object_loaded() in the error path in > klp_init_object_loaded(). > > Reported-by: [email protected] > Closes: https://lore.kernel.org/r/[email protected] > Signed-off-by: Petr Mladek <[email protected]>
Acked-by: Song Liu <[email protected]> With one nitpick > --- > kernel/livepatch/core.c | 30 ++++++++++++++++++++---------- > 1 file changed, 20 insertions(+), 10 deletions(-) > > diff --git a/kernel/livepatch/core.c b/kernel/livepatch/core.c > index cdb25949f73b..1e59a3cc0895 100644 > --- a/kernel/livepatch/core.c > +++ b/kernel/livepatch/core.c > @@ -725,18 +725,20 @@ static void __klp_free_funcs(struct klp_object *obj, > bool nops_only) > } > > /* Clean up when a patched object is unloaded */ > -static void klp_free_object_loaded(struct klp_object *obj) > +static void klp_free_object_loaded(struct klp_patch *patch, > + struct klp_object *obj) nit: Do we still need to fit every line in 80 characters? checkpatch.pl only enforce 100 characters these days. Thanks Song > { > struct klp_func *func; [...]
