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
  ...

1 files changed, 372 insertions, 0 deletions

diff --git a/security/apparmor/task.c b/security/apparmor/task.c
new file mode 100644
index 000000000..b9fb37381
--- /dev/null
+++ b/security/apparmor/task.c
@@ -0,0 +1,372 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * AppArmor security module
+ *
+ * This file contains AppArmor task related definitions and mediation
+ *
+ * Copyright 2017 Canonical Ltd.
+ *
+ * TODO
+ * If a task uses change_hat it currently does not return to the old
+ * cred or task context but instead creates a new one.  Ideally the task
+ * should return to the previous cred if it has not been modified.
+ */
+
+#include <linux/gfp.h>
+#include <linux/ptrace.h>
+
+#include "include/path.h"
+#include "include/audit.h"
+#include "include/cred.h"
+#include "include/policy.h"
+#include "include/task.h"
+
+/**
+ * aa_get_task_label - Get another task's label
+ * @task: task to query  (NOT NULL)
+ *
+ * Returns: counted reference to @task's label
+ */
+struct aa_label *aa_get_task_label(struct task_struct *task)
+{
+	struct aa_label *p;
+
+	rcu_read_lock();
+	p = aa_get_newest_cred_label(__task_cred(task));
+	rcu_read_unlock();
+
+	return p;
+}
+
+/**
+ * aa_replace_current_label - replace the current tasks label
+ * @label: new label  (NOT NULL)
+ *
+ * Returns: 0 or error on failure
+ */
+int aa_replace_current_label(struct aa_label *label)
+{
+	struct aa_label *old = aa_current_raw_label();
+	struct aa_task_ctx *ctx = task_ctx(current);
+	struct cred *new;
+
+	AA_BUG(!label);
+
+	if (old == label)
+		return 0;
+
+	if (current_cred() != current_real_cred())
+		return -EBUSY;
+
+	new  = prepare_creds();
+	if (!new)
+		return -ENOMEM;
+
+	if (ctx->nnp && label_is_stale(ctx->nnp)) {
+		struct aa_label *tmp = ctx->nnp;
+
+		ctx->nnp = aa_get_newest_label(tmp);
+		aa_put_label(tmp);
+	}
+	if (unconfined(label) || (labels_ns(old) != labels_ns(label)))
+		/*
+		 * if switching to unconfined or a different label namespace
+		 * clear out context state
+		 */
+		aa_clear_task_ctx_trans(task_ctx(current));
+
+	/*
+	 * be careful switching cred label, when racing replacement it
+	 * is possible that the cred labels's->proxy->label is the reference
+	 * keeping @label valid, so make sure to get its reference before
+	 * dropping the reference on the cred's label
+	 */
+	aa_get_label(label);
+	aa_put_label(cred_label(new));
+	set_cred_label(new, label);
+
+	commit_creds(new);
+	return 0;
+}
+
+
+/**
+ * aa_set_current_onexec - set the tasks change_profile to happen onexec
+ * @label: system label to set at exec  (MAYBE NULL to clear value)
+ * @stack: whether stacking should be done
+ */
+void aa_set_current_onexec(struct aa_label *label, bool stack)
+{
+	struct aa_task_ctx *ctx = task_ctx(current);
+
+	aa_get_label(label);
+	aa_put_label(ctx->onexec);
+	ctx->onexec = label;
+	ctx->token = stack;
+}
+
+/**
+ * aa_set_current_hat - set the current tasks hat
+ * @label: label to set as the current hat  (NOT NULL)
+ * @token: token value that must be specified to change from the hat
+ *
+ * Do switch of tasks hat.  If the task is currently in a hat
+ * validate the token to match.
+ *
+ * Returns: 0 or error on failure
+ */
+int aa_set_current_hat(struct aa_label *label, u64 token)
+{
+	struct aa_task_ctx *ctx = task_ctx(current);
+	struct cred *new;
+
+	new = prepare_creds();
+	if (!new)
+		return -ENOMEM;
+	AA_BUG(!label);
+
+	if (!ctx->previous) {
+		/* transfer refcount */
+		ctx->previous = cred_label(new);
+		ctx->token = token;
+	} else if (ctx->token == token) {
+		aa_put_label(cred_label(new));
+	} else {
+		/* previous_profile && ctx->token != token */
+		abort_creds(new);
+		return -EACCES;
+	}
+
+	set_cred_label(new, aa_get_newest_label(label));
+	/* clear exec on switching context */
+	aa_put_label(ctx->onexec);
+	ctx->onexec = NULL;
+
+	commit_creds(new);
+	return 0;
+}
+
+/**
+ * aa_restore_previous_label - exit from hat context restoring previous label
+ * @token: the token that must be matched to exit hat context
+ *
+ * Attempt to return out of a hat to the previous label.  The token
+ * must match the stored token value.
+ *
+ * Returns: 0 or error of failure
+ */
+int aa_restore_previous_label(u64 token)
+{
+	struct aa_task_ctx *ctx = task_ctx(current);
+	struct cred *new;
+
+	if (ctx->token != token)
+		return -EACCES;
+	/* ignore restores when there is no saved label */
+	if (!ctx->previous)
+		return 0;
+
+	new = prepare_creds();
+	if (!new)
+		return -ENOMEM;
+
+	aa_put_label(cred_label(new));
+	set_cred_label(new, aa_get_newest_label(ctx->previous));
+	AA_BUG(!cred_label(new));
+	/* clear exec && prev information when restoring to previous context */
+	aa_clear_task_ctx_trans(ctx);
+
+	commit_creds(new);
+
+	return 0;
+}
+
+/**
+ * audit_ptrace_mask - convert mask to permission string
+ * @mask: permission mask to convert
+ *
+ * Returns: pointer to static string
+ */
+static const char *audit_ptrace_mask(u32 mask)
+{
+	switch (mask) {
+	case MAY_READ:
+		return "read";
+	case MAY_WRITE:
+		return "trace";
+	case AA_MAY_BE_READ:
+		return "readby";
+	case AA_MAY_BE_TRACED:
+		return "tracedby";
+	}
+	return "";
+}
+
+/* call back to audit ptrace fields */
+static void audit_ptrace_cb(struct audit_buffer *ab, void *va)
+{
+	struct common_audit_data *sa = va;
+	struct apparmor_audit_data *ad = aad(sa);
+
+	if (ad->request & AA_PTRACE_PERM_MASK) {
+		audit_log_format(ab, " requested_mask=\"%s\"",
+				 audit_ptrace_mask(ad->request));
+
+		if (ad->denied & AA_PTRACE_PERM_MASK) {
+			audit_log_format(ab, " denied_mask=\"%s\"",
+					 audit_ptrace_mask(ad->denied));
+		}
+	}
+	audit_log_format(ab, " peer=");
+	aa_label_xaudit(ab, labels_ns(ad->subj_label), ad->peer,
+			FLAGS_NONE, GFP_ATOMIC);
+}
+
+/* assumes check for RULE_MEDIATES is already done */
+/* TODO: conditionals */
+static int profile_ptrace_perm(const struct cred *cred,
+			       struct aa_profile *profile,
+			       struct aa_label *peer, u32 request,
+			       struct apparmor_audit_data *ad)
+{
+	struct aa_ruleset *rules = profile->label.rules[0];
+	struct aa_perms perms = { };
+
+	ad->subj_cred = cred;
+	ad->peer = peer;
+	aa_profile_match_label(profile, rules, peer, AA_CLASS_PTRACE, request,
+			       &perms);
+	aa_apply_modes_to_perms(profile, &perms);
+	return aa_check_perms(profile, &perms, request, ad, audit_ptrace_cb);
+}
+
+static int profile_tracee_perm(const struct cred *cred,
+			       struct aa_profile *tracee,
+			       struct aa_label *tracer, u32 request,
+			       struct apparmor_audit_data *ad)
+{
+	if (profile_unconfined(tracee) || unconfined(tracer) ||
+	    !label_mediates(&tracee->label, AA_CLASS_PTRACE))
+		return 0;
+
+	return profile_ptrace_perm(cred, tracee, tracer, request, ad);
+}
+
+static int profile_tracer_perm(const struct cred *cred,
+			       struct aa_profile *tracer,
+			       struct aa_label *tracee, u32 request,
+			       struct apparmor_audit_data *ad)
+{
+	if (profile_unconfined(tracer))
+		return 0;
+
+	if (label_mediates(&tracer->label, AA_CLASS_PTRACE))
+		return profile_ptrace_perm(cred, tracer, tracee, request, ad);
+
+	/* profile uses the old style capability check for ptrace */
+	if (&tracer->label == tracee)
+		return 0;
+
+	ad->subj_label = &tracer->label;
+	ad->peer = tracee;
+	ad->request = 0;
+	ad->error = aa_capable(cred, &tracer->label, CAP_SYS_PTRACE,
+			       CAP_OPT_NONE);
+
+	return aa_audit(AUDIT_APPARMOR_AUTO, tracer, ad, audit_ptrace_cb);
+}
+
+/**
+ * aa_may_ptrace - test if tracer task can trace the tracee
+ * @tracer_cred: cred of task doing the tracing  (NOT NULL)
+ * @tracer: label of the task doing the tracing  (NOT NULL)
+ * @tracee_cred: cred of task to be traced
+ * @tracee: task label to be traced
+ * @request: permission request
+ *
+ * Returns: %0 else error code if permission denied or error
+ */
+int aa_may_ptrace(const struct cred *tracer_cred, struct aa_label *tracer,
+		  const struct cred *tracee_cred, struct aa_label *tracee,
+		  u32 request)
+{
+	struct aa_profile *profile;
+	u32 xrequest = request << PTRACE_PERM_SHIFT;
+	DEFINE_AUDIT_DATA(sa, LSM_AUDIT_DATA_NONE, AA_CLASS_PTRACE, OP_PTRACE);
+
+	return xcheck_labels(tracer, tracee, profile,
+			profile_tracer_perm(tracer_cred, profile, tracee,
+					    request, &sa),
+			profile_tracee_perm(tracee_cred, profile, tracer,
+					    xrequest, &sa));
+}
+
+static const char *get_current_exe_path(char *buffer, int buffer_size)
+{
+	struct file *exe_file;
+	struct path p;
+	const char *path_str;
+
+	exe_file = get_task_exe_file(current);
+	if (!exe_file)
+		return ERR_PTR(-ENOENT);
+	p = exe_file->f_path;
+	path_get(&p);
+
+	if (aa_path_name(&p, FLAG_VIEW_SUBNS, buffer, &path_str, NULL, NULL))
+		path_str = ERR_PTR(-ENOMEM);
+
+	fput(exe_file);
+	path_put(&p);
+
+	return path_str;
+}
+
+/* call back to audit ptrace fields */
+static void audit_ns_cb(struct audit_buffer *ab, void *va)
+{
+	struct apparmor_audit_data *ad = aad_of_va(va);
+	char *buffer;
+	const char *path;
+
+	if (ad->request & AA_USERNS_CREATE)
+		audit_log_format(ab, " requested=\"userns_create\"");
+
+	if (ad->denied & AA_USERNS_CREATE)
+		audit_log_format(ab, " denied=\"userns_create\"");
+
+	buffer = aa_get_buffer(false);
+	if (!buffer)
+		return; // OOM
+	path = get_current_exe_path(buffer, aa_g_path_max);
+	if (!IS_ERR(path))
+		audit_log_format(ab, " execpath=\"%s\"", path);
+	aa_put_buffer(buffer);
+}
+
+int aa_profile_ns_perm(struct aa_profile *profile,
+		       struct apparmor_audit_data *ad,
+		       u32 request)
+{
+	struct aa_perms perms = { };
+	int error = 0;
+
+	ad->subj_label = &profile->label;
+	ad->request = request;
+
+	if (!profile_unconfined(profile)) {
+		struct aa_ruleset *rules = profile->label.rules[0];
+		aa_state_t state;
+
+		state = RULE_MEDIATES(rules, ad->class);
+		if (!state)
+			/* TODO: add flag to complain about unmediated */
+			return 0;
+		perms = *aa_lookup_perms(rules->policy, state);
+		aa_apply_modes_to_perms(profile, &perms);
+		error = aa_check_perms(profile, &perms, request, ad,
+				       audit_ns_cb);
+	}
+
+	return error;
+}