From: Daniel Gomez <[email protected]>
The -EEXIST error code is reserved by the module loading infrastructure
to indicate that a module is already loaded. When a module's init
function returns -EEXIST, userspace tools like kmod interpret this as
"module already loaded" and treat the operation as successful, returning
0 to the user even though the module initialization actually failed.
This follows the precedent set by commit 54416fd76770 ("netfilter:
conntrack: helper: Replace -EEXIST by -EBUSY") which fixed the same
issue in nf_conntrack_helper_register().
Affected modules:
* pkcs8_key_parser x509_key_parser asymmetric_keys dns_resolver
* nvme_keyring pkcs7_test_key rxrpc turris_signing_key
Signed-off-by: Daniel Gomez <[email protected]>
---
The error code -EEXIST is reserved by the kernel module loader to
indicate that a module with the same name is already loaded. When a
module's init function returns -EEXIST, kmod interprets this as "module
already loaded" and reports success instead of failure [1].
The kernel module loader will include a safety net that provides -EEXIST
to -EBUSY with a warning [2], and a documentation patch has been sent to
prevent future occurrences [3].
These affected code paths were identified using a static analysis tool
[4] that traces -EEXIST returns to module_init(). The tool was developed
with AI assistance and all findings were manually validated.
Link: https://lore.kernel.org/all/[email protected]/ [1]
Link:
https://lore.kernel.org/all/[email protected]/
[2]
Link:
https://lore.kernel.org/all/20251218-dev-module-init-eexists-modules-docs-v1-0-361569aa7...@samsung.com/
[3]
Link: https://gitlab.com/-/snippets/4913469 [4]
---
crypto/asymmetric_keys/asymmetric_type.c | 2 +-
security/keys/key.c | 4 ++--
2 files changed, 3 insertions(+), 3 deletions(-)
diff --git a/crypto/asymmetric_keys/asymmetric_type.c
b/crypto/asymmetric_keys/asymmetric_type.c
index 348966ea2175..2c6f3a725102 100644
--- a/crypto/asymmetric_keys/asymmetric_type.c
+++ b/crypto/asymmetric_keys/asymmetric_type.c
@@ -634,7 +634,7 @@ int register_asymmetric_key_parser(struct
asymmetric_key_parser *parser)
if (strcmp(cursor->name, parser->name) == 0) {
pr_err("Asymmetric key parser '%s' already
registered\n",
parser->name);
- ret = -EEXIST;
+ ret = -EBUSY;
goto out;
}
}
diff --git a/security/keys/key.c b/security/keys/key.c
index 3bbdde778631..ed597660f72e 100644
--- a/security/keys/key.c
+++ b/security/keys/key.c
@@ -1219,7 +1219,7 @@ EXPORT_SYMBOL(generic_key_instantiate);
*
* Register a new key type.
*
- * Returns 0 on success or -EEXIST if a type of this name already exists.
+ * Returns 0 on success or -EBUSY if a type of this name already exists.
*/
int register_key_type(struct key_type *ktype)
{
@@ -1228,7 +1228,7 @@ int register_key_type(struct key_type *ktype)
memset(&ktype->lock_class, 0, sizeof(ktype->lock_class));
- ret = -EEXIST;
+ ret = -EBUSY;
down_write(&key_types_sem);
/* disallow key types with the same name */
---
base-commit: 8f0b4cce4481fb22653697cced8d0d04027cb1e8
change-id: 20251218-dev-module-init-eexists-keyring-5b008d7efb40
Best regards,
--
Daniel Gomez <[email protected]>
