On Tue, 10 Oct 2023 at 18:03, Jarkko Sakkinen <jarkko@xxxxxxxxxx> wrote: > > On Fri, 2023-10-06 at 10:48 +0530, Sumit Garg wrote: > > Static calls invocations aren't well supported from module __init and > > __exit functions. Especially the static call from cleanup_trusted() led > > to a crash on x86 kernel with CONFIG_DEBUG_VIRTUAL=y. > > > > However, the usage of static call invocations for trusted_key_init() > > and trusted_key_exit() don't add any value from either a performance or > > security perspective. Hence switch to use indirect function calls instead. > > > > Note here that although it will fix the current crash report, ultimately > > the static call infrastructure should be fixed to either support its > > future usage from module __init and __exit functions or not. > > > > Reported-by: Hyeonggon Yoo <42.hyeyoo@xxxxxxxxx> > > Link: https://lore.kernel.org/lkml/ZRhKq6e5nF%2F4ZIV1@fedora/#t > > Fixes: 5d0682be3189 ("KEYS: trusted: Add generic trusted keys framework") > > Signed-off-by: Sumit Garg <sumit.garg@xxxxxxxxxx> > > --- > > > > Changes in v2: > > - Polish commit message as per comments from Mimi > > > > security/keys/trusted-keys/trusted_core.c | 13 +++++-------- > > 1 file changed, 5 insertions(+), 8 deletions(-) > > > > diff --git a/security/keys/trusted-keys/trusted_core.c b/security/keys/trusted-keys/trusted_core.c > > index c6fc50d67214..85fb5c22529a 100644 > > --- a/security/keys/trusted-keys/trusted_core.c > > +++ b/security/keys/trusted-keys/trusted_core.c > > @@ -44,13 +44,12 @@ static const struct trusted_key_source trusted_key_sources[] = { > > #endif > > }; > > > > -DEFINE_STATIC_CALL_NULL(trusted_key_init, *trusted_key_sources[0].ops->init); > > DEFINE_STATIC_CALL_NULL(trusted_key_seal, *trusted_key_sources[0].ops->seal); > > DEFINE_STATIC_CALL_NULL(trusted_key_unseal, > > *trusted_key_sources[0].ops->unseal); > > DEFINE_STATIC_CALL_NULL(trusted_key_get_random, > > *trusted_key_sources[0].ops->get_random); > > -DEFINE_STATIC_CALL_NULL(trusted_key_exit, *trusted_key_sources[0].ops->exit); > > +static void (*trusted_key_exit)(void); > > static unsigned char migratable; > > > > enum { > > @@ -359,19 +358,16 @@ static int __init init_trusted(void) > > if (!get_random) > > get_random = kernel_get_random; > > > > - static_call_update(trusted_key_init, > > - trusted_key_sources[i].ops->init); > > static_call_update(trusted_key_seal, > > trusted_key_sources[i].ops->seal); > > static_call_update(trusted_key_unseal, > > trusted_key_sources[i].ops->unseal); > > static_call_update(trusted_key_get_random, > > get_random); > > - static_call_update(trusted_key_exit, > > - trusted_key_sources[i].ops->exit); > > + trusted_key_exit = trusted_key_sources[i].ops->exit; > > migratable = trusted_key_sources[i].ops->migratable; > > > > - ret = static_call(trusted_key_init)(); > > + ret = trusted_key_sources[i].ops->init(); > > if (!ret) > > break; > > } > > @@ -388,7 +384,8 @@ static int __init init_trusted(void) > > > > static void __exit cleanup_trusted(void) > > { > > - static_call_cond(trusted_key_exit)(); > > + if (trusted_key_exit) > > + (*trusted_key_exit)(); > > } > > > > late_initcall(init_trusted); > > Would it be less confusing to require trusted_key_exit from each? > It is already required for each trust source to provide exit callback but this NULL check was added via this fix [1] in case there isn't any trust source present. [1] https://lkml.kernel.org/stable/20220126184155.220814-1-dave.kleikamp@xxxxxxxxxx/ -Sumit > BR, Jarkko >
