From: Mickaël Salaün <[email protected]>
The blacklist_init() function calls panic() for memory allocation
errors. This change documents the reason why we don't return -ENODEV.
Suggested-by: Paul Moore <[email protected]> [1]
Requested-by: Jarkko Sakkinen <[email protected]> [1]
Link: https://lore.kernel.org/r/[email protected] [1]
Reviewed-by: Paul Moore <[email protected]>
Reviewed-by: Jarkko Sakkinen <[email protected]>
Signed-off-by: Mickaël Salaün <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
---
Changes since v1:
* Fix commit subject spelling spotted by David Woodhouse.
* Reword one sentence as suggested by Paul Moore.
* Add Reviewed-by Paul Moore.
* Add Reviewed-by Jarkko Sakkinen.
---
certs/blacklist.c | 9 +++++++++
1 file changed, 9 insertions(+)
diff --git a/certs/blacklist.c b/certs/blacklist.c
index 486ce0dd8e9c..25094ea73600 100644
--- a/certs/blacklist.c
+++ b/certs/blacklist.c
@@ -307,6 +307,15 @@ static int restrict_link_for_blacklist(struct key *dest_keyring,
/*
* Initialise the blacklist
+ *
+ * The blacklist_init() function is registered as an initcall via
+ * device_initcall(). As a result if the blacklist_init() function fails for
+ * any reason the kernel continues to execute. While cleanly returning -ENODEV
+ * could be acceptable for some non-critical kernel parts, if the blacklist
+ * keyring fails to load it defeats the certificate/key based deny list for
+ * signed modules. If a critical piece of security functionality that users
+ * expect to be present fails to initialize, panic()ing is likely the right
+ * thing to do.
*/
static int __init blacklist_init(void)
{
--
2.35.1