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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
commit4352b8aee98005853aa63f57d6377282de17a33f (patch)
tree27614d7a9ef05c32d089004e104364ce42324837 /security/landlock/audit.c
downloadlinux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz
linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
Pull I3C updates from Alexandre Belloni: "A new driver this cycle, for the AMD AXI I3C controller. There are also new features such as IBI wakeup support, SETAASA device discovery and ACPI support for the the DAA methods, meaning we can now communicate with the SPD devices on DDR5 modules. New driver: - AMD AXI I3C master controller Subsystem: - I3C Common Command Code (CCC) handling improvements, especially around GET CCCs - SETAASA device discovery support - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as well as I2C devices on I3C bus - IBI-based wakeup support Drivers: - dw: SETAASA support - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C controller support, PIO queue management support for HCI v1.2 - renesas: improve suspend to RAM support, add runtime PM support" * tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits) i3c: dw: reduce do_daa time if there's no client i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2 i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode i3c: dw: rename "pclk" to "apb" to match dt-binding i3c: dw: make struct dw_i3c_cmd smaller i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding i3c: renesas: Don't register devices when ENTDAA times out i3c: master: dw-i3c-master: fix OD timing for first broadcast i3c: mipi-i3c-hci: Advertise IBI wakeup capability i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev() i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI i3c: master: Reject IBI requests from non-IBI-capable devices i3c: master: Add helper to query bus wakeup requirements i3c: master: Report wakeup events for IBIs i3c: master: Support IBI-based wakeup capability i3c: master: Fix potential UAF in i3c_device_match() i3c: master: Fix potential UAF in i3c_device_uevent() i3c: Make dev->desc locking assumptions explicit i3c: master: Fix use-after-free of master->this ...
Diffstat (limited to 'security/landlock/audit.c')
-rw-r--r--security/landlock/audit.c237
1 files changed, 237 insertions, 0 deletions
diff --git a/security/landlock/audit.c b/security/landlock/audit.c
new file mode 100644
index 000000000..e02963834
--- /dev/null
+++ b/security/landlock/audit.c
@@ -0,0 +1,237 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Landlock - Audit helpers
+ *
+ * Copyright © 2023-2025 Microsoft Corporation
+ */
+
+#include <linux/audit.h>
+#include <linux/bitops.h>
+#include <linux/landlock.h>
+#include <linux/lsm_audit.h>
+#include <linux/pid.h>
+#include <uapi/linux/landlock.h>
+
+#include "access.h"
+#include "audit.h"
+#include "common.h"
+#include "cred.h"
+#include "domain.h"
+#include "limits.h"
+#include "log.h"
+
+/*
+ * Access-right and scope names are built from the lists shared with the trace
+ * events (see <linux/landlock.h>). The designated initializer places each name
+ * at its bit index, so the lookup stays O(1) and does not depend on the entry
+ * order. log_blockers() adds the "fs."/"net."/"scope." category prefix.
+ */
+#define _LANDLOCK_NAME_ENTRY(mask, name) [BIT_INDEX(mask)] = name
+
+static const char *const fs_access_strings[] = { _LANDLOCK_ACCESS_FS_NAMES };
+
+static_assert(ARRAY_SIZE(fs_access_strings) == LANDLOCK_NUM_ACCESS_FS);
+
+static const char *const net_access_strings[] = { _LANDLOCK_ACCESS_NET_NAMES };
+
+static_assert(ARRAY_SIZE(net_access_strings) == LANDLOCK_NUM_ACCESS_NET);
+
+static const char *const scope_strings[] = { _LANDLOCK_SCOPE_NAMES };
+
+static_assert(ARRAY_SIZE(scope_strings) == LANDLOCK_NUM_SCOPE);
+
+#undef _LANDLOCK_NAME_ENTRY
+
+static __attribute_const__ const char *
+get_blocker(const enum landlock_request_type type,
+ const unsigned long access_bit)
+{
+ switch (type) {
+ case LANDLOCK_REQUEST_PTRACE:
+ WARN_ON_ONCE(access_bit != -1);
+ return "ptrace";
+
+ case LANDLOCK_REQUEST_FS_CHANGE_TOPOLOGY:
+ WARN_ON_ONCE(access_bit != -1);
+ return "change_topology";
+
+ case LANDLOCK_REQUEST_FS_ACCESS:
+ if (WARN_ON_ONCE(access_bit >= ARRAY_SIZE(fs_access_strings)))
+ return "unknown";
+ return fs_access_strings[access_bit];
+
+ case LANDLOCK_REQUEST_NET_ACCESS:
+ if (WARN_ON_ONCE(access_bit >= ARRAY_SIZE(net_access_strings)))
+ return "unknown";
+ return net_access_strings[access_bit];
+
+ case LANDLOCK_REQUEST_SCOPE_ABSTRACT_UNIX_SOCKET:
+ WARN_ON_ONCE(access_bit != -1);
+ return scope_strings[BIT_INDEX(
+ LANDLOCK_SCOPE_ABSTRACT_UNIX_SOCKET)];
+
+ case LANDLOCK_REQUEST_SCOPE_SIGNAL:
+ WARN_ON_ONCE(access_bit != -1);
+ return scope_strings[BIT_INDEX(LANDLOCK_SCOPE_SIGNAL)];
+ }
+
+ WARN_ON_ONCE(1);
+ return "unknown";
+}
+
+/*
+ * Returns the audit category prefix prepended to the unprefixed blocker name
+ * returned by get_blocker() (filesystem and network access rights,
+ * change_topology, and scopes). The ptrace blocker is standalone and carries
+ * its full name in get_blocker(), so it uses no prefix.
+ */
+static __attribute_const__ const char *
+blocker_prefix(const enum landlock_request_type type)
+{
+ switch (type) {
+ case LANDLOCK_REQUEST_PTRACE:
+ return "";
+
+ case LANDLOCK_REQUEST_FS_CHANGE_TOPOLOGY:
+ case LANDLOCK_REQUEST_FS_ACCESS:
+ return "fs.";
+
+ case LANDLOCK_REQUEST_NET_ACCESS:
+ return "net.";
+
+ case LANDLOCK_REQUEST_SCOPE_ABSTRACT_UNIX_SOCKET:
+ case LANDLOCK_REQUEST_SCOPE_SIGNAL:
+ return "scope.";
+ }
+
+ WARN_ON_ONCE(1);
+ return "";
+}
+
+static void log_blockers(struct audit_buffer *const ab,
+ const enum landlock_request_type type,
+ const access_mask_t access)
+{
+ const unsigned long access_mask = access;
+ const char *const prefix = blocker_prefix(type);
+ unsigned long access_bit;
+ bool is_first = true;
+
+ for_each_set_bit(access_bit, &access_mask, BITS_PER_TYPE(access)) {
+ audit_log_format(ab, "%s%s%s", is_first ? "" : ",", prefix,
+ get_blocker(type, access_bit));
+ is_first = false;
+ }
+ if (is_first)
+ audit_log_format(ab, "%s%s", prefix, get_blocker(type, -1));
+}
+
+static void log_domain(struct landlock_hierarchy *const hierarchy)
+{
+ struct audit_buffer *ab;
+
+ /* Ignores already logged domains. */
+ if (READ_ONCE(hierarchy->log_status) == LANDLOCK_LOG_RECORDED)
+ return;
+
+ /* Uses consistent allocation flags wrt common_lsm_audit(). */
+ ab = audit_log_start(audit_context(), GFP_ATOMIC | __GFP_NOWARN,
+ AUDIT_LANDLOCK_DOMAIN);
+ if (!ab)
+ return;
+
+ WARN_ON_ONCE(hierarchy->id == 0);
+ audit_log_format(
+ ab,
+ "domain=%llx status=allocated mode=enforcing pid=%d uid=%u exe=",
+ hierarchy->id, pid_nr(hierarchy->details->pid),
+ hierarchy->details->uid);
+ audit_log_untrustedstring(ab, hierarchy->details->exe_path);
+ audit_log_format(ab, " comm=");
+ audit_log_untrustedstring(ab, hierarchy->details->comm);
+ audit_log_end(ab);
+
+ /*
+ * There may be race condition leading to logging of the same domain
+ * several times but that is OK.
+ */
+ WRITE_ONCE(hierarchy->log_status, LANDLOCK_LOG_RECORDED);
+}
+
+/**
+ * landlock_audit_denial - Create an audit record for a denied access request
+ *
+ * @request: Detail of the user space request.
+ * @youngest_denied: The youngest hierarchy node that denied the access.
+ * @missing: The set of denied access rights.
+ * @logged: Whether the denial is selected for logging, as computed by
+ * landlock_log_denial() (domain policy and quiet rules).
+ *
+ * Emits the record when audit is enabled and the denial is selected for
+ * logging.
+ */
+void landlock_audit_denial(const struct landlock_request *const request,
+ struct landlock_hierarchy *const youngest_denied,
+ const access_mask_t missing, const bool logged)
+{
+ struct audit_buffer *ab;
+
+ if (!audit_enabled)
+ return;
+
+ /*
+ * Skips denials the domain's policy or a quiet rule excludes from
+ * logging (folded into @logged by landlock_log_denial()).
+ */
+ if (!logged)
+ return;
+
+ /* Uses consistent allocation flags wrt common_lsm_audit(). */
+ ab = audit_log_start(audit_context(), GFP_ATOMIC | __GFP_NOWARN,
+ AUDIT_LANDLOCK_ACCESS);
+ if (!ab)
+ return;
+
+ audit_log_format(ab, "domain=%llx blockers=", youngest_denied->id);
+ log_blockers(ab, request->type, missing);
+ audit_log_lsm_data(ab, &request->audit);
+ audit_log_end(ab);
+
+ /* Logs this domain the first time it shows in log. */
+ log_domain(youngest_denied);
+}
+
+/**
+ * landlock_audit_free_domain - Create an audit record on domain deallocation
+ *
+ * @hierarchy: The domain's hierarchy being deallocated.
+ *
+ * Only domains which previously appeared in the audit logs are logged again.
+ * This is useful to know when a domain will never show again in the audit log.
+ *
+ * Called from landlock_log_free_domain().
+ */
+void landlock_audit_free_domain(const struct landlock_hierarchy *const hierarchy)
+{
+ struct audit_buffer *ab;
+
+ if (!audit_enabled)
+ return;
+
+ /* Ignores domains that were not logged. */
+ if (READ_ONCE(hierarchy->log_status) != LANDLOCK_LOG_RECORDED)
+ return;
+
+ /*
+ * If logging of domain allocation succeeded, warns about failure to log
+ * domain deallocation to highlight unbalanced domain lifetime logs.
+ */
+ ab = audit_log_start(audit_context(), GFP_KERNEL,
+ AUDIT_LANDLOCK_DOMAIN);
+ if (!ab)
+ return;
+
+ audit_log_format(ab, "domain=%llx status=deallocated denials=%llu",
+ hierarchy->id, atomic64_read(&hierarchy->num_denials));
+ audit_log_end(ab);
+}