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Diffstat (limited to 'security/landlock/syscalls.c')
-rw-r--r--security/landlock/syscalls.c61
1 files changed, 30 insertions, 31 deletions
diff --git a/security/landlock/syscalls.c b/security/landlock/syscalls.c
index 4ed8e70c25ed..cf9e0483e542 100644
--- a/security/landlock/syscalls.c
+++ b/security/landlock/syscalls.c
@@ -10,6 +10,7 @@
#include <linux/anon_inodes.h>
#include <linux/build_bug.h>
#include <linux/capability.h>
+#include <linux/cleanup.h>
#include <linux/compiler_types.h>
#include <linux/dcache.h>
#include <linux/err.h>
@@ -159,7 +160,9 @@ static const struct file_operations ruleset_fops = {
* the new ruleset.
* @size: Size of the pointed &struct landlock_ruleset_attr (needed for
* backward and forward compatibility).
- * @flags: Supported value: %LANDLOCK_CREATE_RULESET_VERSION.
+ * @flags: Supported value:
+ * - %LANDLOCK_CREATE_RULESET_VERSION
+ * - %LANDLOCK_CREATE_RULESET_ERRATA
*
* This system call enables to create a new Landlock ruleset, and returns the
* related file descriptor on success.
@@ -168,6 +171,10 @@ static const struct file_operations ruleset_fops = {
* 0, then the returned value is the highest supported Landlock ABI version
* (starting at 1).
*
+ * If @flags is %LANDLOCK_CREATE_RULESET_ERRATA and @attr is NULL and @size is
+ * 0, then the returned value is a bitmask of fixed issues for the current
+ * Landlock ABI version.
+ *
* Possible returned errors are:
*
* - %EOPNOTSUPP: Landlock is supported by the kernel but disabled at boot time;
@@ -191,9 +198,15 @@ SYSCALL_DEFINE3(landlock_create_ruleset,
return -EOPNOTSUPP;
if (flags) {
- if ((flags == LANDLOCK_CREATE_RULESET_VERSION) && !attr &&
- !size)
- return LANDLOCK_ABI_VERSION;
+ if (attr || size)
+ return -EINVAL;
+
+ if (flags == LANDLOCK_CREATE_RULESET_VERSION)
+ return landlock_abi_version;
+
+ if (flags == LANDLOCK_CREATE_RULESET_ERRATA)
+ return landlock_errata;
+
return -EINVAL;
}
@@ -234,6 +247,8 @@ SYSCALL_DEFINE3(landlock_create_ruleset,
return ruleset_fd;
}
+const int landlock_abi_version = LANDLOCK_ABI_VERSION;
+
/*
* Returns an owned ruleset from a FD. It is thus needed to call
* landlock_put_ruleset() on the return value.
@@ -398,8 +413,7 @@ SYSCALL_DEFINE4(landlock_add_rule, const int, ruleset_fd,
const enum landlock_rule_type, rule_type,
const void __user *const, rule_attr, const __u32, flags)
{
- struct landlock_ruleset *ruleset;
- int err;
+ struct landlock_ruleset *ruleset __free(landlock_put_ruleset) = NULL;
if (!is_initialized())
return -EOPNOTSUPP;
@@ -415,17 +429,12 @@ SYSCALL_DEFINE4(landlock_add_rule, const int, ruleset_fd,
switch (rule_type) {
case LANDLOCK_RULE_PATH_BENEATH:
- err = add_rule_path_beneath(ruleset, rule_attr);
- break;
+ return add_rule_path_beneath(ruleset, rule_attr);
case LANDLOCK_RULE_NET_PORT:
- err = add_rule_net_port(ruleset, rule_attr);
- break;
+ return add_rule_net_port(ruleset, rule_attr);
default:
- err = -EINVAL;
- break;
+ return -EINVAL;
}
- landlock_put_ruleset(ruleset);
- return err;
}
/* Enforcement */
@@ -456,10 +465,10 @@ SYSCALL_DEFINE4(landlock_add_rule, const int, ruleset_fd,
SYSCALL_DEFINE2(landlock_restrict_self, const int, ruleset_fd, const __u32,
flags)
{
- struct landlock_ruleset *new_dom, *ruleset;
+ struct landlock_ruleset *new_dom,
+ *ruleset __free(landlock_put_ruleset) = NULL;
struct cred *new_cred;
struct landlock_cred_security *new_llcred;
- int err;
if (!is_initialized())
return -EOPNOTSUPP;
@@ -483,10 +492,9 @@ SYSCALL_DEFINE2(landlock_restrict_self, const int, ruleset_fd, const __u32,
/* Prepares new credentials. */
new_cred = prepare_creds();
- if (!new_cred) {
- err = -ENOMEM;
- goto out_put_ruleset;
- }
+ if (!new_cred)
+ return -ENOMEM;
+
new_llcred = landlock_cred(new_cred);
/*
@@ -495,21 +503,12 @@ SYSCALL_DEFINE2(landlock_restrict_self, const int, ruleset_fd, const __u32,
*/
new_dom = landlock_merge_ruleset(new_llcred->domain, ruleset);
if (IS_ERR(new_dom)) {
- err = PTR_ERR(new_dom);
- goto out_put_creds;
+ abort_creds(new_cred);
+ return PTR_ERR(new_dom);
}
/* Replaces the old (prepared) domain. */
landlock_put_ruleset(new_llcred->domain);
new_llcred->domain = new_dom;
-
- landlock_put_ruleset(ruleset);
return commit_creds(new_cred);
-
-out_put_creds:
- abort_creds(new_cred);
-
-out_put_ruleset:
- landlock_put_ruleset(ruleset);
- return err;
}