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landlock_merge_ruleset() checks for a NULL ruleset after dereferencing it in lockdep_assert_held(). Move the assertion after the check so the defensive path remains effective. The mask-validation comment originated in landlock_add_fs_access_mask() to explain that its WARN_ON_ONCE() checked a caller invariant. It became self-referential when this helper and its network and scope counterparts were inlined into landlock_create_ruleset(). Restate the invariant without naming the caller. Keep both as defensive callee checks. Moving the assertion preserves the NULL check's ability to warn and return -EINVAL, while invalid masks remain warned about and masked. Reported-by: Günther Noack <gnoack@google.com> Closes: https://patch.msgid.link/aobYhIt3vcs2xN0b@google.com Closes: https://patch.msgid.link/aobasxUDQ8b7GYXl@google.com Reviewed-by: Günther Noack <gnoack@google.com> Link: https://patch.msgid.link/20260907103609.113325-1-mic@digikod.net Signed-off-by: Mickaël Salaün <mic@digikod.net>
777 lines
21 KiB
C
777 lines
21 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* Landlock - Domain management
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*
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* Copyright © 2016-2020 Mickaël Salaün <mic@digikod.net>
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* Copyright © 2018-2020 ANSSI
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* Copyright © 2024-2025 Microsoft Corporation
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* Copyright © 2026 Cloudflare, Inc.
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*/
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#include <kunit/test.h>
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#include <linux/bitops.h>
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#include <linux/bits.h>
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#include <linux/cleanup.h>
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#include <linux/cred.h>
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#include <linux/err.h>
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#include <linux/file.h>
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#include <linux/lockdep.h>
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#include <linux/mm.h>
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#include <linux/mutex.h>
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#include <linux/overflow.h>
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#include <linux/path.h>
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#include <linux/pid.h>
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#include <linux/rbtree.h>
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#include <linux/refcount.h>
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#include <linux/sched.h>
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#include <linux/signal.h>
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#include <linux/slab.h>
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#include <linux/uidgid.h>
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#include <linux/workqueue.h>
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#include "access.h"
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#include "common.h"
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#include "domain.h"
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#include "id.h"
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#include "limits.h"
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#include "ruleset.h"
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static void build_check_domain(void)
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{
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const struct landlock_domain domain = {
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.num_layers = ~0,
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};
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BUILD_BUG_ON(domain.num_layers < LANDLOCK_MAX_NUM_LAYERS);
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}
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static struct landlock_domain *create_domain(const u32 num_layers)
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{
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struct landlock_domain *new_domain;
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build_check_domain();
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new_domain = kzalloc_flex(*new_domain, handled_masks, num_layers,
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GFP_KERNEL_ACCOUNT);
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if (!new_domain)
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return ERR_PTR(-ENOMEM);
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refcount_set(&new_domain->usage, 1);
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new_domain->rules.root_inode = RB_ROOT;
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#if IS_ENABLED(CONFIG_INET)
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new_domain->rules.root_net_port = RB_ROOT;
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#endif /* IS_ENABLED(CONFIG_INET) */
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new_domain->num_layers = num_layers;
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return new_domain;
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}
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static void free_domain(struct landlock_domain *const domain)
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{
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might_sleep();
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landlock_free_rules(&domain->rules);
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landlock_put_hierarchy(domain->hierarchy);
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kfree(domain);
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}
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void landlock_put_domain(struct landlock_domain *const domain)
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{
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might_sleep();
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if (domain && refcount_dec_and_test(&domain->usage))
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free_domain(domain);
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}
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static void free_domain_work(struct work_struct *const work)
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{
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struct landlock_domain *domain;
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domain = container_of(work, struct landlock_domain, work_free);
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free_domain(domain);
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}
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void landlock_put_domain_deferred(struct landlock_domain *const domain)
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{
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if (domain && refcount_dec_and_test(&domain->usage)) {
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INIT_WORK(&domain->work_free, free_domain_work);
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schedule_work(&domain->work_free);
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}
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}
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/* The returned access has the same lifetime as the domain. */
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static const struct landlock_rule *
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find_rule(const struct landlock_domain *const domain,
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const struct landlock_id id)
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{
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const struct rb_root *root;
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const struct rb_node *node;
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root = landlock_get_rule_root((struct landlock_rules *)&domain->rules,
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id.type);
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if (IS_ERR(root))
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return NULL;
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node = root->rb_node;
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while (node) {
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struct landlock_rule *this =
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rb_entry(node, struct landlock_rule, node);
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if (this->key.data == id.key.data)
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return this;
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if (this->key.data < id.key.data)
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node = node->rb_right;
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else
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node = node->rb_left;
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}
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return NULL;
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}
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/**
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* landlock_unmask_layers - Remove the access rights in @masks which are
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* granted by a matching rule
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*
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* Looks up the rule matching @id in @domain, then updates the set of
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* (per-layer) unfulfilled access rights @masks so that all the access rights
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* granted by that rule are removed (because they are now fulfilled).
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*
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* @domain: The Landlock domain to search for a matching rule.
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* @id: Identifier for the rule target (e.g. inode, port).
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* @masks: A matrix of unfulfilled access rights for each layer.
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* @matched_rule: Optional output for the matched rule (for tracing); set to
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* the matching rule when non-NULL, unchanged otherwise.
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*
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* Return: True if the request is allowed (i.e. the access rights granted all
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* remaining unfulfilled access rights and masks has no leftover set bits).
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*/
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bool landlock_unmask_layers(const struct landlock_domain *const domain,
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const struct landlock_id id,
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struct layer_masks *masks,
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const struct landlock_rule **matched_rule)
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{
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const struct landlock_rule *rule;
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if (!masks)
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return true;
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rule = find_rule(domain, id);
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if (!rule)
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return false;
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if (matched_rule)
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*matched_rule = rule;
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/*
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* An access is granted if, for each policy layer, at least one rule
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* encountered on the pathwalk grants the requested access, regardless
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* of its position in the layer stack. We must then check the remaining
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* layers for each inode, from the first added layer to the last one.
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* When there are multiple requested accesses, for each policy layer,
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* the full set of requested accesses may not be granted by only one
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* rule, but by the union (binary OR) of multiple rules. For example,
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* /a/b <execute> + /a <read> grants /a/b <execute + read>.
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*
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* This function is called once per matching rule during the pathwalk,
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* progressively clearing bits in @masks. The overall access decision
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* is per-layer: access is granted iff masks->layers[l].access == 0 for
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* all layers l. When two independent mechanisms can each grant access
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* within a layer (e.g. a path rule OR a scope exception), the
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* composition must evaluate per-layer: FOR-ALL l (A(l) OR B(l)), not
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* (FOR-ALL l A(l)) OR (FOR-ALL l B(l)), to prevent bypass when
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* different layers grant via different mechanisms.
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*/
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for (size_t i = 0; i < rule->num_layers; i++) {
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const struct landlock_layer *const layer = &rule->layers[i];
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/* Clear the bits where the layer in the rule grants access. */
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masks->layers[layer->level - 1].access &= ~layer->access;
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#ifdef CONFIG_SECURITY_LANDLOCK_LOG
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/* Collect rule flags for each layer. */
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if (layer->flags.quiet)
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masks->layers[layer->level - 1].quiet = true;
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#endif /* CONFIG_SECURITY_LANDLOCK_LOG */
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}
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for (size_t i = 0; i < ARRAY_SIZE(masks->layers); i++) {
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if (masks->layers[i].access)
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return false;
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}
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return true;
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}
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typedef access_mask_t
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get_access_mask_t(const struct landlock_domain *const domain,
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const u16 layer_level);
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/**
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* landlock_init_layer_masks - Initialize layer masks from an access request
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*
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* Populates @masks such that for each access right in @access_request, the bits
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* for all the layers are set where this access right is handled. Rule flags
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* are also zeroed.
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*
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* @domain: The domain that defines the current restrictions.
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* @access_request: The requested access rights to check.
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* @masks: Layer access masks to populate.
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* @key_type: The key type to switch between access masks of different types.
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*
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* Return: An access mask where each access right bit is set which is handled in
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* any of the active layers in @domain.
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*/
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access_mask_t
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landlock_init_layer_masks(const struct landlock_domain *const domain,
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const access_mask_t access_request,
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struct layer_masks *const masks,
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const enum landlock_key_type key_type)
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{
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access_mask_t handled_accesses = 0;
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get_access_mask_t *get_access_mask;
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switch (key_type) {
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case LANDLOCK_KEY_INODE:
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get_access_mask = landlock_get_fs_access_mask;
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break;
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#if IS_ENABLED(CONFIG_INET)
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case LANDLOCK_KEY_NET_PORT:
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get_access_mask = landlock_get_net_access_mask;
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break;
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#endif /* IS_ENABLED(CONFIG_INET) */
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default:
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WARN_ON_ONCE(1);
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return 0;
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}
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/* An empty access request can happen because of O_WRONLY | O_RDWR. */
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if (!access_request)
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return 0;
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for (size_t i = 0; i < domain->num_layers; i++) {
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const access_mask_t handled = get_access_mask(domain, i);
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masks->layers[i].access = access_request & handled;
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handled_accesses |= masks->layers[i].access;
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#ifdef CONFIG_SECURITY_LANDLOCK_LOG
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masks->layers[i].quiet = false;
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#endif /* CONFIG_SECURITY_LANDLOCK_LOG */
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}
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for (size_t i = domain->num_layers; i < ARRAY_SIZE(masks->layers);
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i++) {
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masks->layers[i].access = 0;
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#ifdef CONFIG_SECURITY_LANDLOCK_LOG
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masks->layers[i].quiet = false;
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#endif /* CONFIG_SECURITY_LANDLOCK_LOG */
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}
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return handled_accesses;
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}
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static int merge_tree(struct landlock_domain *const dst,
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struct landlock_ruleset *const src,
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const enum landlock_key_type key_type)
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{
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struct landlock_rule *walker_rule, *next_rule;
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struct rb_root *src_root;
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int err = 0;
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might_sleep();
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lockdep_assert_held(&src->lock);
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src_root = landlock_get_rule_root(&src->rules, key_type);
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if (IS_ERR(src_root))
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return PTR_ERR(src_root);
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/* Merges the @src tree. */
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rbtree_postorder_for_each_entry_safe(walker_rule, next_rule, src_root,
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node) {
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struct landlock_layer layers[] = { {
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.level = dst->num_layers,
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} };
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const struct landlock_id id = {
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.key = walker_rule->key,
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.type = key_type,
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};
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if (WARN_ON_ONCE(walker_rule->num_layers != 1))
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return -EINVAL;
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if (WARN_ON_ONCE(walker_rule->layers[0].level != 0))
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return -EINVAL;
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layers[0].access = walker_rule->layers[0].access;
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layers[0].flags = walker_rule->layers[0].flags;
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err = landlock_store_rule(&dst->rules, id, &layers,
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ARRAY_SIZE(layers));
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if (err)
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return err;
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}
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return err;
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}
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static int merge_ruleset(struct landlock_domain *const dst,
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struct landlock_ruleset *const src)
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{
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int err = 0;
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might_sleep();
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/* Should already be checked by landlock_merge_ruleset() */
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if (WARN_ON_ONCE(!src))
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return 0;
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/* Only merge into a domain. */
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if (WARN_ON_ONCE(!dst || !dst->hierarchy))
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return -EINVAL;
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lockdep_assert_held(&src->lock);
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/* Stacks the new layer. */
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if (WARN_ON_ONCE(dst->num_layers < 1))
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return -EINVAL;
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dst->handled_masks[dst->num_layers - 1] =
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landlock_upgrade_handled_access_masks(src->handled_masks);
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/* Merges the @src inode tree. */
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err = merge_tree(dst, src, LANDLOCK_KEY_INODE);
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if (err)
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return err;
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#if IS_ENABLED(CONFIG_INET)
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/* Merges the @src network port tree. */
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err = merge_tree(dst, src, LANDLOCK_KEY_NET_PORT);
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if (err)
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return err;
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#endif /* IS_ENABLED(CONFIG_INET) */
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return 0;
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}
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static int inherit_tree(struct landlock_domain *const parent,
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struct landlock_domain *const child,
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const enum landlock_key_type key_type)
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{
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struct landlock_rule *walker_rule, *next_rule;
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struct rb_root *parent_root;
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int err = 0;
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might_sleep();
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parent_root = landlock_get_rule_root(&parent->rules, key_type);
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if (IS_ERR(parent_root))
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return PTR_ERR(parent_root);
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/* Copies the @parent inode or network tree. */
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rbtree_postorder_for_each_entry_safe(walker_rule, next_rule,
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parent_root, node) {
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const struct landlock_id id = {
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.key = walker_rule->key,
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.type = key_type,
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};
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err = landlock_store_rule(&child->rules, id,
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&walker_rule->layers,
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walker_rule->num_layers);
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if (err)
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return err;
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}
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return err;
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}
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static int inherit_ruleset(struct landlock_domain *const parent,
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struct landlock_domain *const child)
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{
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int err = 0;
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might_sleep();
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if (!parent)
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return 0;
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/* Copies the @parent inode tree. */
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err = inherit_tree(parent, child, LANDLOCK_KEY_INODE);
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if (err)
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return err;
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#if IS_ENABLED(CONFIG_INET)
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/* Copies the @parent network port tree. */
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err = inherit_tree(parent, child, LANDLOCK_KEY_NET_PORT);
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if (err)
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return err;
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#endif /* IS_ENABLED(CONFIG_INET) */
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if (WARN_ON_ONCE(child->num_layers <= parent->num_layers))
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return -EINVAL;
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/*
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* Copies the parent layer stack and leaves a space for the new layer.
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*/
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memcpy(child->handled_masks, parent->handled_masks,
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flex_array_size(parent, handled_masks, parent->num_layers));
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if (WARN_ON_ONCE(!parent->hierarchy))
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return -EINVAL;
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landlock_get_hierarchy(parent->hierarchy);
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child->hierarchy->parent = parent->hierarchy;
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return 0;
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}
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/**
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* landlock_merge_ruleset - Merge a ruleset with a domain
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*
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* @parent: Parent domain.
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* @ruleset: New ruleset to be merged.
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*
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* The current task is requesting to be restricted. The subjective credentials
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* must not be in an overridden state. cf. landlock_init_hierarchy_log().
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*
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* The caller must hold @ruleset->lock.
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*
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* Return: A new domain merging @parent and @ruleset on success, or ERR_PTR() on
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* failure. If @parent is NULL, the new domain duplicates @ruleset.
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*/
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struct landlock_domain *
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landlock_merge_ruleset(struct landlock_domain *const parent,
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struct landlock_ruleset *const ruleset)
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{
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struct landlock_domain *new_dom __free(landlock_put_domain) = NULL;
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u32 num_layers;
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int err;
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might_sleep();
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if (WARN_ON_ONCE(!ruleset))
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return ERR_PTR(-EINVAL);
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lockdep_assert_held(&ruleset->lock);
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if (parent) {
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if (parent->num_layers >= LANDLOCK_MAX_NUM_LAYERS)
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return ERR_PTR(-E2BIG);
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num_layers = parent->num_layers + 1;
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} else {
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num_layers = 1;
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}
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/* Creates a new domain... */
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new_dom = create_domain(num_layers);
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if (IS_ERR(new_dom))
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return new_dom;
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new_dom->hierarchy =
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kzalloc_obj(*new_dom->hierarchy, GFP_KERNEL_ACCOUNT);
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if (!new_dom->hierarchy)
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return ERR_PTR(-ENOMEM);
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refcount_set(&new_dom->hierarchy->usage, 1);
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/* ...as a child of @parent... */
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err = inherit_ruleset(parent, new_dom);
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if (err)
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return ERR_PTR(err);
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/* ...and including @ruleset. */
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err = merge_ruleset(new_dom, ruleset);
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if (err)
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return ERR_PTR(err);
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err = landlock_init_hierarchy_log(new_dom->hierarchy);
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if (err)
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return ERR_PTR(err);
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#ifdef CONFIG_SECURITY_LANDLOCK_LOG
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new_dom->hierarchy->quiet_masks = ruleset->quiet_masks;
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#endif /* CONFIG_SECURITY_LANDLOCK_LOG */
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return no_free_ptr(new_dom);
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}
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#ifdef CONFIG_SECURITY_LANDLOCK_LOG
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/**
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* get_current_exe - Get the current's executable path, if any
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*
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* @exe_str: Returned pointer to a path string with a lifetime tied to the
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* returned buffer, if any.
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* @exe_size: Returned size of @exe_str (including the trailing null
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* character), if any.
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*
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* Return: A pointer to an allocated buffer where @exe_str point to, %NULL if
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* there is no executable path, or an error otherwise.
|
|
*/
|
|
static const void *get_current_exe(const char **const exe_str,
|
|
size_t *const exe_size)
|
|
{
|
|
const size_t buffer_size = LANDLOCK_PATH_MAX_SIZE;
|
|
struct mm_struct *mm = current->mm;
|
|
struct file *file __free(fput) = NULL;
|
|
char *buffer __free(kfree) = NULL;
|
|
const char *exe;
|
|
ssize_t size;
|
|
|
|
if (!mm)
|
|
return NULL;
|
|
|
|
file = get_mm_exe_file(mm);
|
|
if (!file)
|
|
return NULL;
|
|
|
|
buffer = kmalloc(buffer_size, GFP_KERNEL);
|
|
if (!buffer)
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
exe = d_path(&file->f_path, buffer, buffer_size);
|
|
if (WARN_ON_ONCE(IS_ERR(exe)))
|
|
/* Should never happen according to LANDLOCK_PATH_MAX_SIZE. */
|
|
return ERR_CAST(exe);
|
|
|
|
size = buffer + buffer_size - exe;
|
|
if (WARN_ON_ONCE(size <= 0))
|
|
return ERR_PTR(-ENAMETOOLONG);
|
|
|
|
*exe_size = size;
|
|
*exe_str = exe;
|
|
return no_free_ptr(buffer);
|
|
}
|
|
|
|
/*
|
|
* Return: A newly allocated object describing a domain, or an error
|
|
* otherwise.
|
|
*/
|
|
static struct landlock_details *get_current_details(void)
|
|
{
|
|
/* Cf. audit_log_d_path_exe() */
|
|
static const char null_path[] = "(null)";
|
|
const char *path_str = null_path;
|
|
size_t path_size = sizeof(null_path);
|
|
const void *buffer __free(kfree) = NULL;
|
|
struct landlock_details *details;
|
|
|
|
buffer = get_current_exe(&path_str, &path_size);
|
|
if (IS_ERR(buffer))
|
|
return ERR_CAST(buffer);
|
|
|
|
/*
|
|
* Create the new details according to the path's length. Account to
|
|
* the calling task's memcg, like the other Landlock per-domain
|
|
* allocations, even if it may not control the related size.
|
|
*/
|
|
details =
|
|
kzalloc_flex(*details, exe_path, path_size, GFP_KERNEL_ACCOUNT);
|
|
if (!details)
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
memcpy(details->exe_path, path_str, path_size);
|
|
details->pid = get_pid(task_tgid(current));
|
|
details->uid = from_kuid(&init_user_ns, current_uid());
|
|
get_task_comm(details->comm, current);
|
|
return details;
|
|
}
|
|
|
|
/**
|
|
* landlock_init_hierarchy_log - Partially initialize landlock_hierarchy
|
|
*
|
|
* @hierarchy: The hierarchy to initialize.
|
|
*
|
|
* The current task is referenced as the domain that is enforcing the
|
|
* restriction. The subjective credentials must not be in an overridden state.
|
|
*
|
|
* @hierarchy->parent and @hierarchy->usage should already be set.
|
|
*
|
|
* Return: 0 on success, -errno on failure.
|
|
*/
|
|
int landlock_init_hierarchy_log(struct landlock_hierarchy *const hierarchy)
|
|
{
|
|
struct landlock_details *details;
|
|
|
|
details = get_current_details();
|
|
if (IS_ERR(details))
|
|
return PTR_ERR(details);
|
|
|
|
hierarchy->details = details;
|
|
hierarchy->id = landlock_get_id_range(1);
|
|
/*
|
|
* The hierarchy is born unobservable: landlock_restrict_self() moves it
|
|
* out of LANDLOCK_LOG_UNCOMMITTED once it has emitted the creation
|
|
* event, so the matching free_domain event fires for it and not for a
|
|
* hierarchy whose creation was never observed.
|
|
*/
|
|
hierarchy->log_status = LANDLOCK_LOG_UNCOMMITTED;
|
|
hierarchy->log_same_exec = true;
|
|
hierarchy->log_new_exec = false;
|
|
atomic64_set(&hierarchy->num_denials, 0);
|
|
return 0;
|
|
}
|
|
|
|
static deny_masks_t
|
|
get_layer_deny_mask(const access_mask_t all_existing_optional_access,
|
|
const unsigned long access_bit, const size_t layer)
|
|
{
|
|
unsigned long access_weight;
|
|
|
|
/* This may require change with new object types. */
|
|
WARN_ON_ONCE(all_existing_optional_access !=
|
|
_LANDLOCK_ACCESS_FS_OPTIONAL);
|
|
|
|
if (WARN_ON_ONCE(layer >= LANDLOCK_MAX_NUM_LAYERS))
|
|
return 0;
|
|
|
|
access_weight = hweight_long(all_existing_optional_access &
|
|
GENMASK(access_bit, 0));
|
|
if (WARN_ON_ONCE(access_weight < 1))
|
|
return 0;
|
|
|
|
return layer
|
|
<< ((access_weight - 1) * HWEIGHT(LANDLOCK_MAX_NUM_LAYERS - 1));
|
|
}
|
|
|
|
/**
|
|
* landlock_get_quiet_optional_accesses - Get optional accesses which are
|
|
* covered by quiet rule flags.
|
|
*
|
|
* @all_existing_optional_access: Bitmask of valid optional accesses.
|
|
* @deny_masks: Domain layer levels that denied each optional access (the
|
|
* deny_masks field on struct landlock_file_security).
|
|
* @masks: The struct layer_masks collected during the path walk.
|
|
*
|
|
* Return: a bitmask of which optional accesses are denied by layers for which
|
|
* the quiet flag was collected during the path walk.
|
|
*/
|
|
optional_access_t landlock_get_quiet_optional_accesses(
|
|
const access_mask_t all_existing_optional_access,
|
|
const deny_masks_t deny_masks, const struct layer_masks *const masks)
|
|
{
|
|
const unsigned long access_opt = all_existing_optional_access;
|
|
size_t access_index = 0;
|
|
unsigned long access_bit;
|
|
optional_access_t quiet_optional_accesses = 0;
|
|
|
|
/* This will require change with new object types. */
|
|
WARN_ON_ONCE(access_opt != _LANDLOCK_ACCESS_FS_OPTIONAL);
|
|
|
|
for_each_set_bit(access_bit, &access_opt,
|
|
BITS_PER_TYPE(access_mask_t)) {
|
|
const u8 layer =
|
|
(deny_masks >> (access_index *
|
|
HWEIGHT(LANDLOCK_MAX_NUM_LAYERS - 1))) &
|
|
(LANDLOCK_MAX_NUM_LAYERS - 1);
|
|
|
|
if (masks->layers[layer].quiet)
|
|
quiet_optional_accesses |= BIT(access_index);
|
|
access_index++;
|
|
}
|
|
return quiet_optional_accesses;
|
|
}
|
|
|
|
#ifdef CONFIG_SECURITY_LANDLOCK_KUNIT_TEST
|
|
|
|
static void test_get_layer_deny_mask(struct kunit *const test)
|
|
{
|
|
const unsigned long truncate = BIT_INDEX(LANDLOCK_ACCESS_FS_TRUNCATE);
|
|
const unsigned long ioctl_dev = BIT_INDEX(LANDLOCK_ACCESS_FS_IOCTL_DEV);
|
|
|
|
KUNIT_EXPECT_EQ(test, 0,
|
|
get_layer_deny_mask(_LANDLOCK_ACCESS_FS_OPTIONAL,
|
|
truncate, 0));
|
|
KUNIT_EXPECT_EQ(test, 0x3,
|
|
get_layer_deny_mask(_LANDLOCK_ACCESS_FS_OPTIONAL,
|
|
truncate, 3));
|
|
|
|
KUNIT_EXPECT_EQ(test, 0,
|
|
get_layer_deny_mask(_LANDLOCK_ACCESS_FS_OPTIONAL,
|
|
ioctl_dev, 0));
|
|
KUNIT_EXPECT_EQ(test, 0xf0,
|
|
get_layer_deny_mask(_LANDLOCK_ACCESS_FS_OPTIONAL,
|
|
ioctl_dev, 15));
|
|
}
|
|
|
|
#endif /* CONFIG_SECURITY_LANDLOCK_KUNIT_TEST */
|
|
|
|
deny_masks_t
|
|
landlock_get_deny_masks(const access_mask_t all_existing_optional_access,
|
|
const access_mask_t optional_access,
|
|
const struct layer_masks *const masks)
|
|
{
|
|
const unsigned long access_opt = optional_access;
|
|
unsigned long access_bit;
|
|
deny_masks_t deny_masks = 0;
|
|
access_mask_t all_denied = 0;
|
|
|
|
/* This may require change with new object types. */
|
|
WARN_ON_ONCE(!access_mask_subset(optional_access,
|
|
all_existing_optional_access));
|
|
|
|
if (WARN_ON_ONCE(!masks))
|
|
return 0;
|
|
|
|
if (WARN_ON_ONCE(!access_opt))
|
|
return 0;
|
|
|
|
for (ssize_t i = ARRAY_SIZE(masks->layers) - 1; i >= 0; i--) {
|
|
const access_mask_t denied = masks->layers[i].access &
|
|
optional_access;
|
|
const unsigned long newly_denied = denied & ~all_denied;
|
|
|
|
if (!newly_denied)
|
|
continue;
|
|
|
|
for_each_set_bit(access_bit, &newly_denied,
|
|
8 * sizeof(access_mask_t)) {
|
|
deny_masks |= get_layer_deny_mask(
|
|
all_existing_optional_access, access_bit, i);
|
|
}
|
|
all_denied |= denied;
|
|
}
|
|
return deny_masks;
|
|
}
|
|
|
|
#ifdef CONFIG_SECURITY_LANDLOCK_KUNIT_TEST
|
|
|
|
static void test_landlock_get_deny_masks(struct kunit *const test)
|
|
{
|
|
const struct layer_masks layers1 = {
|
|
.layers[0].access = LANDLOCK_ACCESS_FS_EXECUTE |
|
|
LANDLOCK_ACCESS_FS_IOCTL_DEV,
|
|
.layers[1].access = LANDLOCK_ACCESS_FS_TRUNCATE,
|
|
.layers[2].access = LANDLOCK_ACCESS_FS_IOCTL_DEV,
|
|
.layers[9].access = LANDLOCK_ACCESS_FS_EXECUTE,
|
|
};
|
|
|
|
KUNIT_EXPECT_EQ(test, 0x1,
|
|
landlock_get_deny_masks(_LANDLOCK_ACCESS_FS_OPTIONAL,
|
|
LANDLOCK_ACCESS_FS_TRUNCATE,
|
|
&layers1));
|
|
KUNIT_EXPECT_EQ(test, 0x20,
|
|
landlock_get_deny_masks(_LANDLOCK_ACCESS_FS_OPTIONAL,
|
|
LANDLOCK_ACCESS_FS_IOCTL_DEV,
|
|
&layers1));
|
|
KUNIT_EXPECT_EQ(
|
|
test, 0x21,
|
|
landlock_get_deny_masks(_LANDLOCK_ACCESS_FS_OPTIONAL,
|
|
LANDLOCK_ACCESS_FS_TRUNCATE |
|
|
LANDLOCK_ACCESS_FS_IOCTL_DEV,
|
|
&layers1));
|
|
}
|
|
|
|
#endif /* CONFIG_SECURITY_LANDLOCK_KUNIT_TEST */
|
|
|
|
#ifdef CONFIG_SECURITY_LANDLOCK_KUNIT_TEST
|
|
|
|
static struct kunit_case test_cases[] = {
|
|
/* clang-format off */
|
|
KUNIT_CASE(test_get_layer_deny_mask),
|
|
KUNIT_CASE(test_landlock_get_deny_masks),
|
|
{}
|
|
/* clang-format on */
|
|
};
|
|
|
|
static struct kunit_suite test_suite = {
|
|
.name = "landlock_domain",
|
|
.test_cases = test_cases,
|
|
};
|
|
|
|
kunit_test_suite(test_suite);
|
|
|
|
#endif /* CONFIG_SECURITY_LANDLOCK_KUNIT_TEST */
|
|
|
|
#endif /* CONFIG_SECURITY_LANDLOCK_LOG */
|