6.5-stable review patch. If anyone has any objections, please let me know.
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From: Sumit Garg sumit.garg@linaro.org
commit 01bbafc63b65689cb179ca537971286bc27f3b74 upstream.
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-and-tested-by: Hyeonggon Yoo 42.hyeyoo@gmail.com 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@linaro.org Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- security/keys/trusted-keys/trusted_core.c | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-)
--- 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 t #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);