diff options
Diffstat (limited to 'security/landlock/ruleset.c')
| -rw-r--r-- | security/landlock/ruleset.c | 67 |
1 files changed, 30 insertions, 37 deletions
diff --git a/security/landlock/ruleset.c b/security/landlock/ruleset.c index e0a5fbf9201a..ce7940efea51 100644 --- a/security/landlock/ruleset.c +++ b/security/landlock/ruleset.c @@ -8,11 +8,13 @@ #include <linux/bits.h> #include <linux/bug.h> +#include <linux/cleanup.h> #include <linux/compiler_types.h> #include <linux/err.h> #include <linux/errno.h> #include <linux/kernel.h> #include <linux/lockdep.h> +#include <linux/mutex.h> #include <linux/overflow.h> #include <linux/rbtree.h> #include <linux/refcount.h> @@ -20,6 +22,9 @@ #include <linux/spinlock.h> #include <linux/workqueue.h> +#include "access.h" +#include "audit.h" +#include "domain.h" #include "limits.h" #include "object.h" #include "ruleset.h" @@ -52,12 +57,13 @@ static struct landlock_ruleset *create_ruleset(const u32 num_layers) struct landlock_ruleset * landlock_create_ruleset(const access_mask_t fs_access_mask, - const access_mask_t net_access_mask) + const access_mask_t net_access_mask, + const access_mask_t scope_mask) { struct landlock_ruleset *new_ruleset; /* Informs about useless ruleset. */ - if (!fs_access_mask && !net_access_mask) + if (!fs_access_mask && !net_access_mask && !scope_mask) return ERR_PTR(-ENOMSG); new_ruleset = create_ruleset(1); if (IS_ERR(new_ruleset)) @@ -66,6 +72,8 @@ landlock_create_ruleset(const access_mask_t fs_access_mask, landlock_add_fs_access_mask(new_ruleset, fs_access_mask, 0); if (net_access_mask) landlock_add_net_access_mask(new_ruleset, net_access_mask, 0); + if (scope_mask) + landlock_add_scope_mask(new_ruleset, scope_mask, 0); return new_ruleset; } @@ -118,7 +126,7 @@ create_rule(const struct landlock_id id, return ERR_PTR(-ENOMEM); RB_CLEAR_NODE(&new_rule->node); if (is_object_pointer(id.type)) { - /* This should be catched by insert_rule(). */ + /* This should have been caught by insert_rule(). */ WARN_ON_ONCE(!id.key.object); landlock_get_object(id.key.object); } @@ -169,13 +177,9 @@ static void build_check_ruleset(void) .num_rules = ~0, .num_layers = ~0, }; - typeof(ruleset.access_masks[0]) access_masks = ~0; BUILD_BUG_ON(ruleset.num_rules < LANDLOCK_MAX_NUM_RULES); BUILD_BUG_ON(ruleset.num_layers < LANDLOCK_MAX_NUM_LAYERS); - BUILD_BUG_ON(access_masks < - ((LANDLOCK_MASK_ACCESS_FS << LANDLOCK_SHIFT_ACCESS_FS) | - (LANDLOCK_MASK_ACCESS_NET << LANDLOCK_SHIFT_ACCESS_NET))); } /** @@ -305,22 +309,6 @@ int landlock_insert_rule(struct landlock_ruleset *const ruleset, return insert_rule(ruleset, id, &layers, ARRAY_SIZE(layers)); } -static void get_hierarchy(struct landlock_hierarchy *const hierarchy) -{ - if (hierarchy) - refcount_inc(&hierarchy->usage); -} - -static void put_hierarchy(struct landlock_hierarchy *hierarchy) -{ - while (hierarchy && refcount_dec_and_test(&hierarchy->usage)) { - const struct landlock_hierarchy *const freeme = hierarchy; - - hierarchy = hierarchy->parent; - kfree(freeme); - } -} - static int merge_tree(struct landlock_ruleset *const dst, struct landlock_ruleset *const src, const enum landlock_key_type key_type) @@ -385,7 +373,8 @@ static int merge_ruleset(struct landlock_ruleset *const dst, err = -EINVAL; goto out_unlock; } - dst->access_masks[dst->num_layers - 1] = src->access_masks[0]; + dst->access_masks[dst->num_layers - 1] = + landlock_upgrade_handled_access_masks(src->access_masks[0]); /* Merges the @src inode tree. */ err = merge_tree(dst, src, LANDLOCK_KEY_INODE); @@ -474,7 +463,7 @@ static int inherit_ruleset(struct landlock_ruleset *const parent, err = -EINVAL; goto out_unlock; } - get_hierarchy(parent->hierarchy); + landlock_get_hierarchy(parent->hierarchy); child->hierarchy->parent = parent->hierarchy; out_unlock: @@ -498,7 +487,7 @@ static void free_ruleset(struct landlock_ruleset *const ruleset) free_rule(freeme, LANDLOCK_KEY_NET_PORT); #endif /* IS_ENABLED(CONFIG_INET) */ - put_hierarchy(ruleset->hierarchy); + landlock_put_hierarchy(ruleset->hierarchy); kfree(ruleset); } @@ -517,6 +506,7 @@ static void free_ruleset_work(struct work_struct *const work) free_ruleset(ruleset); } +/* Only called by hook_cred_free(). */ void landlock_put_ruleset_deferred(struct landlock_ruleset *const ruleset) { if (ruleset && refcount_dec_and_test(&ruleset->usage)) { @@ -531,6 +521,9 @@ void landlock_put_ruleset_deferred(struct landlock_ruleset *const ruleset) * @parent: Parent domain. * @ruleset: New ruleset to be merged. * + * The current task is requesting to be restricted. The subjective credentials + * must not be in an overridden state. cf. landlock_init_hierarchy_log(). + * * Returns the intersection of @parent and @ruleset, or returns @parent if * @ruleset is empty, or returns a duplicate of @ruleset if @parent is empty. */ @@ -538,7 +531,7 @@ struct landlock_ruleset * landlock_merge_ruleset(struct landlock_ruleset *const parent, struct landlock_ruleset *const ruleset) { - struct landlock_ruleset *new_dom; + struct landlock_ruleset *new_dom __free(landlock_put_ruleset) = NULL; u32 num_layers; int err; @@ -558,29 +551,29 @@ landlock_merge_ruleset(struct landlock_ruleset *const parent, new_dom = create_ruleset(num_layers); if (IS_ERR(new_dom)) return new_dom; + new_dom->hierarchy = kzalloc(sizeof(*new_dom->hierarchy), GFP_KERNEL_ACCOUNT); - if (!new_dom->hierarchy) { - err = -ENOMEM; - goto out_put_dom; - } + if (!new_dom->hierarchy) + return ERR_PTR(-ENOMEM); + refcount_set(&new_dom->hierarchy->usage, 1); /* ...as a child of @parent... */ err = inherit_ruleset(parent, new_dom); if (err) - goto out_put_dom; + return ERR_PTR(err); /* ...and including @ruleset. */ err = merge_ruleset(new_dom, ruleset); if (err) - goto out_put_dom; + return ERR_PTR(err); - return new_dom; + err = landlock_init_hierarchy_log(new_dom->hierarchy); + if (err) + return ERR_PTR(err); -out_put_dom: - landlock_put_ruleset(new_dom); - return ERR_PTR(err); + return no_free_ptr(new_dom); } /* |