From: Mickaël Salaün <mic@xxxxxxxxxxxxxxxxxxx> 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 <paul@xxxxxxxxxxxxxx> [1] Requested-by: Jarkko Sakkinen <jarkko@xxxxxxxxxx> [1] Link: https://lore.kernel.org/r/YjeW2r6Wv55Du0bJ@xxxxxx [1] Signed-off-by: Mickaël Salaün <mic@xxxxxxxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20220321174548.510516-2-mic@xxxxxxxxxxx --- certs/blacklist.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/certs/blacklist.c b/certs/blacklist.c index 486ce0dd8e9c..ac26bcf9b9a5 100644 --- a/certs/blacklist.c +++ b/certs/blacklist.c @@ -307,6 +307,14 @@ 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 the functionality doesn't load and the + * kernel continues on executing. 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
