diff --git a/Documentation/networking/dns_resolver.txt b/Documentation/networking/dns_resolver.txt index 7f531ad83285..d86adcdae420 100644 --- a/Documentation/networking/dns_resolver.txt +++ b/Documentation/networking/dns_resolver.txt @@ -102,6 +102,10 @@ implemented in the module can be called after doing: If _expiry is non-NULL, the expiry time (TTL) of the result will be returned also. +The kernel maintains an internal keyring in which it caches looked up keys. +This can be cleared by any process that has the CAP_SYS_ADMIN capability by +the use of KEYCTL_KEYRING_CLEAR on the keyring ID. + =============================== READING DNS KEYS FROM USERSPACE diff --git a/Documentation/security/keys.txt b/Documentation/security/keys.txt index 4d75931d2d79..713ec232c562 100644 --- a/Documentation/security/keys.txt +++ b/Documentation/security/keys.txt @@ -554,6 +554,10 @@ The keyctl syscall functions are: process must have write permission on the keyring, and it must be a keyring (or else error ENOTDIR will result). + This function can also be used to clear special kernel keyrings if they + are appropriately marked if the user has CAP_SYS_ADMIN capability. The + DNS resolver cache keyring is an example of this. + (*) Link a key into a keyring: diff --git a/drivers/char/tpm/Kconfig b/drivers/char/tpm/Kconfig index 7fc75e47e6d0..a048199ce866 100644 --- a/drivers/char/tpm/Kconfig +++ b/drivers/char/tpm/Kconfig @@ -5,7 +5,6 @@ menuconfig TCG_TPM tristate "TPM Hardware Support" depends on HAS_IOMEM - depends on EXPERIMENTAL select SECURITYFS ---help--- If you have a TPM security chip in your system, which diff --git a/fs/cifs/cifsacl.c b/fs/cifs/cifsacl.c index c1b254487388..3cc1b251ca08 100644 --- a/fs/cifs/cifsacl.c +++ b/fs/cifs/cifsacl.c @@ -556,6 +556,7 @@ init_cifs_idmap(void) /* instruct request_key() to use this special keyring as a cache for * the results it looks up */ + set_bit(KEY_FLAG_ROOT_CAN_CLEAR, &keyring->flags); cred->thread_keyring = keyring; cred->jit_keyring = KEY_REQKEY_DEFL_THREAD_KEYRING; root_cred = cred; diff --git a/fs/nfs/idmap.c b/fs/nfs/idmap.c index 2c05f1991e1e..a1bbf7780dfc 100644 --- a/fs/nfs/idmap.c +++ b/fs/nfs/idmap.c @@ -198,6 +198,7 @@ int nfs_idmap_init(void) if (ret < 0) goto failed_put_key; + set_bit(KEY_FLAG_ROOT_CAN_CLEAR, &keyring->flags); cred->thread_keyring = keyring; cred->jit_keyring = KEY_REQKEY_DEFL_THREAD_KEYRING; id_resolver_cache = cred; diff --git a/include/linux/key.h b/include/linux/key.h index 5253471cd2ea..1600ebf717a7 100644 --- a/include/linux/key.h +++ b/include/linux/key.h @@ -155,6 +155,7 @@ struct key { #define KEY_FLAG_IN_QUOTA 3 /* set if key consumes quota */ #define KEY_FLAG_USER_CONSTRUCT 4 /* set if key is being constructed in userspace */ #define KEY_FLAG_NEGATIVE 5 /* set if key is negative */ +#define KEY_FLAG_ROOT_CAN_CLEAR 6 /* set if key can be cleared by root without permission */ /* the description string * - this is used to match a key against search criteria diff --git a/net/dns_resolver/dns_key.c b/net/dns_resolver/dns_key.c index fa000d26dc60..c73bba326d70 100644 --- a/net/dns_resolver/dns_key.c +++ b/net/dns_resolver/dns_key.c @@ -281,6 +281,7 @@ static int __init init_dns_resolver(void) /* instruct request_key() to use this special keyring as a cache for * the results it looks up */ + set_bit(KEY_FLAG_ROOT_CAN_CLEAR, &keyring->flags); cred->thread_keyring = keyring; cred->jit_keyring = KEY_REQKEY_DEFL_THREAD_KEYRING; dns_resolver_cache = cred; diff --git a/security/integrity/ima/Kconfig b/security/integrity/ima/Kconfig index 4f554f20dc97..063298a797e8 100644 --- a/security/integrity/ima/Kconfig +++ b/security/integrity/ima/Kconfig @@ -9,7 +9,7 @@ config IMA select CRYPTO_HMAC select CRYPTO_MD5 select CRYPTO_SHA1 - select TCG_TPM if !S390 && !UML + select TCG_TPM if HAS_IOMEM && !UML select TCG_TIS if TCG_TPM help The Trusted Computing Group(TCG) runtime Integrity diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c index d45061d02fee..0fb643a9c916 100644 --- a/security/integrity/ima/ima_policy.c +++ b/security/integrity/ima/ima_policy.c @@ -62,6 +62,7 @@ static struct ima_measure_rule_entry default_rules[] = { {.action = DONT_MEASURE,.fsmagic = SYSFS_MAGIC,.flags = IMA_FSMAGIC}, {.action = DONT_MEASURE,.fsmagic = DEBUGFS_MAGIC,.flags = IMA_FSMAGIC}, {.action = DONT_MEASURE,.fsmagic = TMPFS_MAGIC,.flags = IMA_FSMAGIC}, + {.action = DONT_MEASURE,.fsmagic = RAMFS_MAGIC,.flags = IMA_FSMAGIC}, {.action = DONT_MEASURE,.fsmagic = SECURITYFS_MAGIC,.flags = IMA_FSMAGIC}, {.action = DONT_MEASURE,.fsmagic = SELINUX_MAGIC,.flags = IMA_FSMAGIC}, {.action = MEASURE,.func = FILE_MMAP,.mask = MAY_EXEC, diff --git a/security/keys/keyctl.c b/security/keys/keyctl.c index 0b3f5d72af1c..6523599e9ac0 100644 --- a/security/keys/keyctl.c +++ b/security/keys/keyctl.c @@ -388,11 +388,24 @@ long keyctl_keyring_clear(key_serial_t ringid) keyring_ref = lookup_user_key(ringid, KEY_LOOKUP_CREATE, KEY_WRITE); if (IS_ERR(keyring_ref)) { ret = PTR_ERR(keyring_ref); + + /* Root is permitted to invalidate certain special keyrings */ + if (capable(CAP_SYS_ADMIN)) { + keyring_ref = lookup_user_key(ringid, 0, 0); + if (IS_ERR(keyring_ref)) + goto error; + if (test_bit(KEY_FLAG_ROOT_CAN_CLEAR, + &key_ref_to_ptr(keyring_ref)->flags)) + goto clear; + goto error_put; + } + goto error; } +clear: ret = keyring_clear(key_ref_to_ptr(keyring_ref)); - +error_put: key_ref_put(keyring_ref); error: return ret;