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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
commit5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch)
treea94efe259b9009378be6d90eb30d2b019d95c194 /security/apparmor/lsm.c
parentInitial commit. (diff)
downloadlinux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.tar.xz
linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.zip
Adding upstream version 5.10.209.upstream/5.10.209
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'security/apparmor/lsm.c')
-rw-r--r--security/apparmor/lsm.c1902
1 files changed, 1902 insertions, 0 deletions
diff --git a/security/apparmor/lsm.c b/security/apparmor/lsm.c
new file mode 100644
index 000000000..585edcc68
--- /dev/null
+++ b/security/apparmor/lsm.c
@@ -0,0 +1,1902 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * AppArmor security module
+ *
+ * This file contains AppArmor LSM hooks.
+ *
+ * Copyright (C) 1998-2008 Novell/SUSE
+ * Copyright 2009-2010 Canonical Ltd.
+ */
+
+#include <linux/lsm_hooks.h>
+#include <linux/moduleparam.h>
+#include <linux/mm.h>
+#include <linux/mman.h>
+#include <linux/mount.h>
+#include <linux/namei.h>
+#include <linux/ptrace.h>
+#include <linux/ctype.h>
+#include <linux/sysctl.h>
+#include <linux/audit.h>
+#include <linux/user_namespace.h>
+#include <linux/netfilter_ipv4.h>
+#include <linux/netfilter_ipv6.h>
+#include <linux/zlib.h>
+#include <net/sock.h>
+#include <uapi/linux/mount.h>
+
+#include "include/apparmor.h"
+#include "include/apparmorfs.h"
+#include "include/audit.h"
+#include "include/capability.h"
+#include "include/cred.h"
+#include "include/file.h"
+#include "include/ipc.h"
+#include "include/net.h"
+#include "include/path.h"
+#include "include/label.h"
+#include "include/policy.h"
+#include "include/policy_ns.h"
+#include "include/procattr.h"
+#include "include/mount.h"
+#include "include/secid.h"
+
+/* Flag indicating whether initialization completed */
+int apparmor_initialized;
+
+union aa_buffer {
+ struct list_head list;
+ char buffer[1];
+};
+
+#define RESERVE_COUNT 2
+static int reserve_count = RESERVE_COUNT;
+static int buffer_count;
+
+static LIST_HEAD(aa_global_buffers);
+static DEFINE_SPINLOCK(aa_buffers_lock);
+
+/*
+ * LSM hook functions
+ */
+
+/*
+ * put the associated labels
+ */
+static void apparmor_cred_free(struct cred *cred)
+{
+ aa_put_label(cred_label(cred));
+ set_cred_label(cred, NULL);
+}
+
+/*
+ * allocate the apparmor part of blank credentials
+ */
+static int apparmor_cred_alloc_blank(struct cred *cred, gfp_t gfp)
+{
+ set_cred_label(cred, NULL);
+ return 0;
+}
+
+/*
+ * prepare new cred label for modification by prepare_cred block
+ */
+static int apparmor_cred_prepare(struct cred *new, const struct cred *old,
+ gfp_t gfp)
+{
+ set_cred_label(new, aa_get_newest_label(cred_label(old)));
+ return 0;
+}
+
+/*
+ * transfer the apparmor data to a blank set of creds
+ */
+static void apparmor_cred_transfer(struct cred *new, const struct cred *old)
+{
+ set_cred_label(new, aa_get_newest_label(cred_label(old)));
+}
+
+static void apparmor_task_free(struct task_struct *task)
+{
+
+ aa_free_task_ctx(task_ctx(task));
+}
+
+static int apparmor_task_alloc(struct task_struct *task,
+ unsigned long clone_flags)
+{
+ struct aa_task_ctx *new = task_ctx(task);
+
+ aa_dup_task_ctx(new, task_ctx(current));
+
+ return 0;
+}
+
+static int apparmor_ptrace_access_check(struct task_struct *child,
+ unsigned int mode)
+{
+ struct aa_label *tracer, *tracee;
+ int error;
+
+ tracer = __begin_current_label_crit_section();
+ tracee = aa_get_task_label(child);
+ error = aa_may_ptrace(tracer, tracee,
+ (mode & PTRACE_MODE_READ) ? AA_PTRACE_READ
+ : AA_PTRACE_TRACE);
+ aa_put_label(tracee);
+ __end_current_label_crit_section(tracer);
+
+ return error;
+}
+
+static int apparmor_ptrace_traceme(struct task_struct *parent)
+{
+ struct aa_label *tracer, *tracee;
+ int error;
+
+ tracee = __begin_current_label_crit_section();
+ tracer = aa_get_task_label(parent);
+ error = aa_may_ptrace(tracer, tracee, AA_PTRACE_TRACE);
+ aa_put_label(tracer);
+ __end_current_label_crit_section(tracee);
+
+ return error;
+}
+
+/* Derived from security/commoncap.c:cap_capget */
+static int apparmor_capget(struct task_struct *target, kernel_cap_t *effective,
+ kernel_cap_t *inheritable, kernel_cap_t *permitted)
+{
+ struct aa_label *label;
+ const struct cred *cred;
+
+ rcu_read_lock();
+ cred = __task_cred(target);
+ label = aa_get_newest_cred_label(cred);
+
+ /*
+ * cap_capget is stacked ahead of this and will
+ * initialize effective and permitted.
+ */
+ if (!unconfined(label)) {
+ struct aa_profile *profile;
+ struct label_it i;
+
+ label_for_each_confined(i, label, profile) {
+ if (COMPLAIN_MODE(profile))
+ continue;
+ *effective = cap_intersect(*effective,
+ profile->caps.allow);
+ *permitted = cap_intersect(*permitted,
+ profile->caps.allow);
+ }
+ }
+ rcu_read_unlock();
+ aa_put_label(label);
+
+ return 0;
+}
+
+static int apparmor_capable(const struct cred *cred, struct user_namespace *ns,
+ int cap, unsigned int opts)
+{
+ struct aa_label *label;
+ int error = 0;
+
+ label = aa_get_newest_cred_label(cred);
+ if (!unconfined(label))
+ error = aa_capable(label, cap, opts);
+ aa_put_label(label);
+
+ return error;
+}
+
+/**
+ * common_perm - basic common permission check wrapper fn for paths
+ * @op: operation being checked
+ * @path: path to check permission of (NOT NULL)
+ * @mask: requested permissions mask
+ * @cond: conditional info for the permission request (NOT NULL)
+ *
+ * Returns: %0 else error code if error or permission denied
+ */
+static int common_perm(const char *op, const struct path *path, u32 mask,
+ struct path_cond *cond)
+{
+ struct aa_label *label;
+ int error = 0;
+
+ label = __begin_current_label_crit_section();
+ if (!unconfined(label))
+ error = aa_path_perm(op, label, path, 0, mask, cond);
+ __end_current_label_crit_section(label);
+
+ return error;
+}
+
+/**
+ * common_perm_cond - common permission wrapper around inode cond
+ * @op: operation being checked
+ * @path: location to check (NOT NULL)
+ * @mask: requested permissions mask
+ *
+ * Returns: %0 else error code if error or permission denied
+ */
+static int common_perm_cond(const char *op, const struct path *path, u32 mask)
+{
+ struct path_cond cond = { d_backing_inode(path->dentry)->i_uid,
+ d_backing_inode(path->dentry)->i_mode
+ };
+
+ if (!path_mediated_fs(path->dentry))
+ return 0;
+
+ return common_perm(op, path, mask, &cond);
+}
+
+/**
+ * common_perm_dir_dentry - common permission wrapper when path is dir, dentry
+ * @op: operation being checked
+ * @dir: directory of the dentry (NOT NULL)
+ * @dentry: dentry to check (NOT NULL)
+ * @mask: requested permissions mask
+ * @cond: conditional info for the permission request (NOT NULL)
+ *
+ * Returns: %0 else error code if error or permission denied
+ */
+static int common_perm_dir_dentry(const char *op, const struct path *dir,
+ struct dentry *dentry, u32 mask,
+ struct path_cond *cond)
+{
+ struct path path = { .mnt = dir->mnt, .dentry = dentry };
+
+ return common_perm(op, &path, mask, cond);
+}
+
+/**
+ * common_perm_rm - common permission wrapper for operations doing rm
+ * @op: operation being checked
+ * @dir: directory that the dentry is in (NOT NULL)
+ * @dentry: dentry being rm'd (NOT NULL)
+ * @mask: requested permission mask
+ *
+ * Returns: %0 else error code if error or permission denied
+ */
+static int common_perm_rm(const char *op, const struct path *dir,
+ struct dentry *dentry, u32 mask)
+{
+ struct inode *inode = d_backing_inode(dentry);
+ struct path_cond cond = { };
+
+ if (!inode || !path_mediated_fs(dentry))
+ return 0;
+
+ cond.uid = inode->i_uid;
+ cond.mode = inode->i_mode;
+
+ return common_perm_dir_dentry(op, dir, dentry, mask, &cond);
+}
+
+/**
+ * common_perm_create - common permission wrapper for operations doing create
+ * @op: operation being checked
+ * @dir: directory that dentry will be created in (NOT NULL)
+ * @dentry: dentry to create (NOT NULL)
+ * @mask: request permission mask
+ * @mode: created file mode
+ *
+ * Returns: %0 else error code if error or permission denied
+ */
+static int common_perm_create(const char *op, const struct path *dir,
+ struct dentry *dentry, u32 mask, umode_t mode)
+{
+ struct path_cond cond = { current_fsuid(), mode };
+
+ if (!path_mediated_fs(dir->dentry))
+ return 0;
+
+ return common_perm_dir_dentry(op, dir, dentry, mask, &cond);
+}
+
+static int apparmor_path_unlink(const struct path *dir, struct dentry *dentry)
+{
+ return common_perm_rm(OP_UNLINK, dir, dentry, AA_MAY_DELETE);
+}
+
+static int apparmor_path_mkdir(const struct path *dir, struct dentry *dentry,
+ umode_t mode)
+{
+ return common_perm_create(OP_MKDIR, dir, dentry, AA_MAY_CREATE,
+ S_IFDIR);
+}
+
+static int apparmor_path_rmdir(const struct path *dir, struct dentry *dentry)
+{
+ return common_perm_rm(OP_RMDIR, dir, dentry, AA_MAY_DELETE);
+}
+
+static int apparmor_path_mknod(const struct path *dir, struct dentry *dentry,
+ umode_t mode, unsigned int dev)
+{
+ return common_perm_create(OP_MKNOD, dir, dentry, AA_MAY_CREATE, mode);
+}
+
+static int apparmor_path_truncate(const struct path *path)
+{
+ return common_perm_cond(OP_TRUNC, path, MAY_WRITE | AA_MAY_SETATTR);
+}
+
+static int apparmor_path_symlink(const struct path *dir, struct dentry *dentry,
+ const char *old_name)
+{
+ return common_perm_create(OP_SYMLINK, dir, dentry, AA_MAY_CREATE,
+ S_IFLNK);
+}
+
+static int apparmor_path_link(struct dentry *old_dentry, const struct path *new_dir,
+ struct dentry *new_dentry)
+{
+ struct aa_label *label;
+ int error = 0;
+
+ if (!path_mediated_fs(old_dentry))
+ return 0;
+
+ label = begin_current_label_crit_section();
+ if (!unconfined(label))
+ error = aa_path_link(label, old_dentry, new_dir, new_dentry);
+ end_current_label_crit_section(label);
+
+ return error;
+}
+
+static int apparmor_path_rename(const struct path *old_dir, struct dentry *old_dentry,
+ const struct path *new_dir, struct dentry *new_dentry)
+{
+ struct aa_label *label;
+ int error = 0;
+
+ if (!path_mediated_fs(old_dentry))
+ return 0;
+
+ label = begin_current_label_crit_section();
+ if (!unconfined(label)) {
+ struct path old_path = { .mnt = old_dir->mnt,
+ .dentry = old_dentry };
+ struct path new_path = { .mnt = new_dir->mnt,
+ .dentry = new_dentry };
+ struct path_cond cond = { d_backing_inode(old_dentry)->i_uid,
+ d_backing_inode(old_dentry)->i_mode
+ };
+
+ error = aa_path_perm(OP_RENAME_SRC, label, &old_path, 0,
+ MAY_READ | AA_MAY_GETATTR | MAY_WRITE |
+ AA_MAY_SETATTR | AA_MAY_DELETE,
+ &cond);
+ if (!error)
+ error = aa_path_perm(OP_RENAME_DEST, label, &new_path,
+ 0, MAY_WRITE | AA_MAY_SETATTR |
+ AA_MAY_CREATE, &cond);
+
+ }
+ end_current_label_crit_section(label);
+
+ return error;
+}
+
+static int apparmor_path_chmod(const struct path *path, umode_t mode)
+{
+ return common_perm_cond(OP_CHMOD, path, AA_MAY_CHMOD);
+}
+
+static int apparmor_path_chown(const struct path *path, kuid_t uid, kgid_t gid)
+{
+ return common_perm_cond(OP_CHOWN, path, AA_MAY_CHOWN);
+}
+
+static int apparmor_inode_getattr(const struct path *path)
+{
+ return common_perm_cond(OP_GETATTR, path, AA_MAY_GETATTR);
+}
+
+static int apparmor_file_open(struct file *file)
+{
+ struct aa_file_ctx *fctx = file_ctx(file);
+ struct aa_label *label;
+ int error = 0;
+
+ if (!path_mediated_fs(file->f_path.dentry))
+ return 0;
+
+ /* If in exec, permission is handled by bprm hooks.
+ * Cache permissions granted by the previous exec check, with
+ * implicit read and executable mmap which are required to
+ * actually execute the image.
+ */
+ if (current->in_execve) {
+ fctx->allow = MAY_EXEC | MAY_READ | AA_EXEC_MMAP;
+ return 0;
+ }
+
+ label = aa_get_newest_cred_label(file->f_cred);
+ if (!unconfined(label)) {
+ struct inode *inode = file_inode(file);
+ struct path_cond cond = { inode->i_uid, inode->i_mode };
+
+ error = aa_path_perm(OP_OPEN, label, &file->f_path, 0,
+ aa_map_file_to_perms(file), &cond);
+ /* todo cache full allowed permissions set and state */
+ fctx->allow = aa_map_file_to_perms(file);
+ }
+ aa_put_label(label);
+
+ return error;
+}
+
+static int apparmor_file_alloc_security(struct file *file)
+{
+ struct aa_file_ctx *ctx = file_ctx(file);
+ struct aa_label *label = begin_current_label_crit_section();
+
+ spin_lock_init(&ctx->lock);
+ rcu_assign_pointer(ctx->label, aa_get_label(label));
+ end_current_label_crit_section(label);
+ return 0;
+}
+
+static void apparmor_file_free_security(struct file *file)
+{
+ struct aa_file_ctx *ctx = file_ctx(file);
+
+ if (ctx)
+ aa_put_label(rcu_access_pointer(ctx->label));
+}
+
+static int common_file_perm(const char *op, struct file *file, u32 mask,
+ bool in_atomic)
+{
+ struct aa_label *label;
+ int error = 0;
+
+ /* don't reaudit files closed during inheritance */
+ if (file->f_path.dentry == aa_null.dentry)
+ return -EACCES;
+
+ label = __begin_current_label_crit_section();
+ error = aa_file_perm(op, label, file, mask, in_atomic);
+ __end_current_label_crit_section(label);
+
+ return error;
+}
+
+static int apparmor_file_receive(struct file *file)
+{
+ return common_file_perm(OP_FRECEIVE, file, aa_map_file_to_perms(file),
+ false);
+}
+
+static int apparmor_file_permission(struct file *file, int mask)
+{
+ return common_file_perm(OP_FPERM, file, mask, false);
+}
+
+static int apparmor_file_lock(struct file *file, unsigned int cmd)
+{
+ u32 mask = AA_MAY_LOCK;
+
+ if (cmd == F_WRLCK)
+ mask |= MAY_WRITE;
+
+ return common_file_perm(OP_FLOCK, file, mask, false);
+}
+
+static int common_mmap(const char *op, struct file *file, unsigned long prot,
+ unsigned long flags, bool in_atomic)
+{
+ int mask = 0;
+
+ if (!file || !file_ctx(file))
+ return 0;
+
+ if (prot & PROT_READ)
+ mask |= MAY_READ;
+ /*
+ * Private mappings don't require write perms since they don't
+ * write back to the files
+ */
+ if ((prot & PROT_WRITE) && !(flags & MAP_PRIVATE))
+ mask |= MAY_WRITE;
+ if (prot & PROT_EXEC)
+ mask |= AA_EXEC_MMAP;
+
+ return common_file_perm(op, file, mask, in_atomic);
+}
+
+static int apparmor_mmap_file(struct file *file, unsigned long reqprot,
+ unsigned long prot, unsigned long flags)
+{
+ return common_mmap(OP_FMMAP, file, prot, flags, GFP_ATOMIC);
+}
+
+static int apparmor_file_mprotect(struct vm_area_struct *vma,
+ unsigned long reqprot, unsigned long prot)
+{
+ return common_mmap(OP_FMPROT, vma->vm_file, prot,
+ !(vma->vm_flags & VM_SHARED) ? MAP_PRIVATE : 0,
+ false);
+}
+
+static int apparmor_sb_mount(const char *dev_name, const struct path *path,
+ const char *type, unsigned long flags, void *data)
+{
+ struct aa_label *label;
+ int error = 0;
+
+ /* Discard magic */
+ if ((flags & MS_MGC_MSK) == MS_MGC_VAL)
+ flags &= ~MS_MGC_MSK;
+
+ flags &= ~AA_MS_IGNORE_MASK;
+
+ label = __begin_current_label_crit_section();
+ if (!unconfined(label)) {
+ if (flags & MS_REMOUNT)
+ error = aa_remount(label, path, flags, data);
+ else if (flags & MS_BIND)
+ error = aa_bind_mount(label, path, dev_name, flags);
+ else if (flags & (MS_SHARED | MS_PRIVATE | MS_SLAVE |
+ MS_UNBINDABLE))
+ error = aa_mount_change_type(label, path, flags);
+ else if (flags & MS_MOVE)
+ error = aa_move_mount(label, path, dev_name);
+ else
+ error = aa_new_mount(label, dev_name, path, type,
+ flags, data);
+ }
+ __end_current_label_crit_section(label);
+
+ return error;
+}
+
+static int apparmor_sb_umount(struct vfsmount *mnt, int flags)
+{
+ struct aa_label *label;
+ int error = 0;
+
+ label = __begin_current_label_crit_section();
+ if (!unconfined(label))
+ error = aa_umount(label, mnt, flags);
+ __end_current_label_crit_section(label);
+
+ return error;
+}
+
+static int apparmor_sb_pivotroot(const struct path *old_path,
+ const struct path *new_path)
+{
+ struct aa_label *label;
+ int error = 0;
+
+ label = aa_get_current_label();
+ if (!unconfined(label))
+ error = aa_pivotroot(label, old_path, new_path);
+ aa_put_label(label);
+
+ return error;
+}
+
+static int apparmor_getprocattr(struct task_struct *task, char *name,
+ char **value)
+{
+ int error = -ENOENT;
+ /* released below */
+ const struct cred *cred = get_task_cred(task);
+ struct aa_task_ctx *ctx = task_ctx(current);
+ struct aa_label *label = NULL;
+
+ if (strcmp(name, "current") == 0)
+ label = aa_get_newest_label(cred_label(cred));
+ else if (strcmp(name, "prev") == 0 && ctx->previous)
+ label = aa_get_newest_label(ctx->previous);
+ else if (strcmp(name, "exec") == 0 && ctx->onexec)
+ label = aa_get_newest_label(ctx->onexec);
+ else
+ error = -EINVAL;
+
+ if (label)
+ error = aa_getprocattr(label, value);
+
+ aa_put_label(label);
+ put_cred(cred);
+
+ return error;
+}
+
+static int apparmor_setprocattr(const char *name, void *value,
+ size_t size)
+{
+ char *command, *largs = NULL, *args = value;
+ size_t arg_size;
+ int error;
+ DEFINE_AUDIT_DATA(sa, LSM_AUDIT_DATA_NONE, OP_SETPROCATTR);
+
+ if (size == 0)
+ return -EINVAL;
+
+ /* AppArmor requires that the buffer must be null terminated atm */
+ if (args[size - 1] != '\0') {
+ /* null terminate */
+ largs = args = kmalloc(size + 1, GFP_KERNEL);
+ if (!args)
+ return -ENOMEM;
+ memcpy(args, value, size);
+ args[size] = '\0';
+ }
+
+ error = -EINVAL;
+ args = strim(args);
+ command = strsep(&args, " ");
+ if (!args)
+ goto out;
+ args = skip_spaces(args);
+ if (!*args)
+ goto out;
+
+ arg_size = size - (args - (largs ? largs : (char *) value));
+ if (strcmp(name, "current") == 0) {
+ if (strcmp(command, "changehat") == 0) {
+ error = aa_setprocattr_changehat(args, arg_size,
+ AA_CHANGE_NOFLAGS);
+ } else if (strcmp(command, "permhat") == 0) {
+ error = aa_setprocattr_changehat(args, arg_size,
+ AA_CHANGE_TEST);
+ } else if (strcmp(command, "changeprofile") == 0) {
+ error = aa_change_profile(args, AA_CHANGE_NOFLAGS);
+ } else if (strcmp(command, "permprofile") == 0) {
+ error = aa_change_profile(args, AA_CHANGE_TEST);
+ } else if (strcmp(command, "stack") == 0) {
+ error = aa_change_profile(args, AA_CHANGE_STACK);
+ } else
+ goto fail;
+ } else if (strcmp(name, "exec") == 0) {
+ if (strcmp(command, "exec") == 0)
+ error = aa_change_profile(args, AA_CHANGE_ONEXEC);
+ else if (strcmp(command, "stack") == 0)
+ error = aa_change_profile(args, (AA_CHANGE_ONEXEC |
+ AA_CHANGE_STACK));
+ else
+ goto fail;
+ } else
+ /* only support the "current" and "exec" process attributes */
+ goto fail;
+
+ if (!error)
+ error = size;
+out:
+ kfree(largs);
+ return error;
+
+fail:
+ aad(&sa)->label = begin_current_label_crit_section();
+ aad(&sa)->info = name;
+ aad(&sa)->error = error = -EINVAL;
+ aa_audit_msg(AUDIT_APPARMOR_DENIED, &sa, NULL);
+ end_current_label_crit_section(aad(&sa)->label);
+ goto out;
+}
+
+/**
+ * apparmor_bprm_committing_creds - do task cleanup on committing new creds
+ * @bprm: binprm for the exec (NOT NULL)
+ */
+static void apparmor_bprm_committing_creds(struct linux_binprm *bprm)
+{
+ struct aa_label *label = aa_current_raw_label();
+ struct aa_label *new_label = cred_label(bprm->cred);
+
+ /* bail out if unconfined or not changing profile */
+ if ((new_label->proxy == label->proxy) ||
+ (unconfined(new_label)))
+ return;
+
+ aa_inherit_files(bprm->cred, current->files);
+
+ current->pdeath_signal = 0;
+
+ /* reset soft limits and set hard limits for the new label */
+ __aa_transition_rlimits(label, new_label);
+}
+
+/**
+ * apparmor_bprm_committed_cred - do cleanup after new creds committed
+ * @bprm: binprm for the exec (NOT NULL)
+ */
+static void apparmor_bprm_committed_creds(struct linux_binprm *bprm)
+{
+ /* clear out temporary/transitional state from the context */
+ aa_clear_task_ctx_trans(task_ctx(current));
+
+ return;
+}
+
+static void apparmor_task_getsecid(struct task_struct *p, u32 *secid)
+{
+ struct aa_label *label = aa_get_task_label(p);
+ *secid = label->secid;
+ aa_put_label(label);
+}
+
+static int apparmor_task_setrlimit(struct task_struct *task,
+ unsigned int resource, struct rlimit *new_rlim)
+{
+ struct aa_label *label = __begin_current_label_crit_section();
+ int error = 0;
+
+ if (!unconfined(label))
+ error = aa_task_setrlimit(label, task, resource, new_rlim);
+ __end_current_label_crit_section(label);
+
+ return error;
+}
+
+static int apparmor_task_kill(struct task_struct *target, struct kernel_siginfo *info,
+ int sig, const struct cred *cred)
+{
+ struct aa_label *cl, *tl;
+ int error;
+
+ if (cred) {
+ /*
+ * Dealing with USB IO specific behavior
+ */
+ cl = aa_get_newest_cred_label(cred);
+ tl = aa_get_task_label(target);
+ error = aa_may_signal(cl, tl, sig);
+ aa_put_label(cl);
+ aa_put_label(tl);
+ return error;
+ }
+
+ cl = __begin_current_label_crit_section();
+ tl = aa_get_task_label(target);
+ error = aa_may_signal(cl, tl, sig);
+ aa_put_label(tl);
+ __end_current_label_crit_section(cl);
+
+ return error;
+}
+
+/**
+ * apparmor_sk_alloc_security - allocate and attach the sk_security field
+ */
+static int apparmor_sk_alloc_security(struct sock *sk, int family, gfp_t flags)
+{
+ struct aa_sk_ctx *ctx;
+
+ ctx = kzalloc(sizeof(*ctx), flags);
+ if (!ctx)
+ return -ENOMEM;
+
+ SK_CTX(sk) = ctx;
+
+ return 0;
+}
+
+/**
+ * apparmor_sk_free_security - free the sk_security field
+ */
+static void apparmor_sk_free_security(struct sock *sk)
+{
+ struct aa_sk_ctx *ctx = SK_CTX(sk);
+
+ SK_CTX(sk) = NULL;
+ aa_put_label(ctx->label);
+ aa_put_label(ctx->peer);
+ kfree(ctx);
+}
+
+/**
+ * apparmor_clone_security - clone the sk_security field
+ */
+static void apparmor_sk_clone_security(const struct sock *sk,
+ struct sock *newsk)
+{
+ struct aa_sk_ctx *ctx = SK_CTX(sk);
+ struct aa_sk_ctx *new = SK_CTX(newsk);
+
+ if (new->label)
+ aa_put_label(new->label);
+ new->label = aa_get_label(ctx->label);
+
+ if (new->peer)
+ aa_put_label(new->peer);
+ new->peer = aa_get_label(ctx->peer);
+}
+
+/**
+ * apparmor_socket_create - check perms before creating a new socket
+ */
+static int apparmor_socket_create(int family, int type, int protocol, int kern)
+{
+ struct aa_label *label;
+ int error = 0;
+
+ AA_BUG(in_interrupt());
+
+ label = begin_current_label_crit_section();
+ if (!(kern || unconfined(label)))
+ error = af_select(family,
+ create_perm(label, family, type, protocol),
+ aa_af_perm(label, OP_CREATE, AA_MAY_CREATE,
+ family, type, protocol));
+ end_current_label_crit_section(label);
+
+ return error;
+}
+
+/**
+ * apparmor_socket_post_create - setup the per-socket security struct
+ *
+ * Note:
+ * - kernel sockets currently labeled unconfined but we may want to
+ * move to a special kernel label
+ * - socket may not have sk here if created with sock_create_lite or
+ * sock_alloc. These should be accept cases which will be handled in
+ * sock_graft.
+ */
+static int apparmor_socket_post_create(struct socket *sock, int family,
+ int type, int protocol, int kern)
+{
+ struct aa_label *label;
+
+ if (kern) {
+ struct aa_ns *ns = aa_get_current_ns();
+
+ label = aa_get_label(ns_unconfined(ns));
+ aa_put_ns(ns);
+ } else
+ label = aa_get_current_label();
+
+ if (sock->sk) {
+ struct aa_sk_ctx *ctx = SK_CTX(sock->sk);
+
+ aa_put_label(ctx->label);
+ ctx->label = aa_get_label(label);
+ }
+ aa_put_label(label);
+
+ return 0;
+}
+
+/**
+ * apparmor_socket_bind - check perms before bind addr to socket
+ */
+static int apparmor_socket_bind(struct socket *sock,
+ struct sockaddr *address, int addrlen)
+{
+ AA_BUG(!sock);
+ AA_BUG(!sock->sk);
+ AA_BUG(!address);
+ AA_BUG(in_interrupt());
+
+ return af_select(sock->sk->sk_family,
+ bind_perm(sock, address, addrlen),
+ aa_sk_perm(OP_BIND, AA_MAY_BIND, sock->sk));
+}
+
+/**
+ * apparmor_socket_connect - check perms before connecting @sock to @address
+ */
+static int apparmor_socket_connect(struct socket *sock,
+ struct sockaddr *address, int addrlen)
+{
+ AA_BUG(!sock);
+ AA_BUG(!sock->sk);
+ AA_BUG(!address);
+ AA_BUG(in_interrupt());
+
+ return af_select(sock->sk->sk_family,
+ connect_perm(sock, address, addrlen),
+ aa_sk_perm(OP_CONNECT, AA_MAY_CONNECT, sock->sk));
+}
+
+/**
+ * apparmor_socket_list - check perms before allowing listen
+ */
+static int apparmor_socket_listen(struct socket *sock, int backlog)
+{
+ AA_BUG(!sock);
+ AA_BUG(!sock->sk);
+ AA_BUG(in_interrupt());
+
+ return af_select(sock->sk->sk_family,
+ listen_perm(sock, backlog),
+ aa_sk_perm(OP_LISTEN, AA_MAY_LISTEN, sock->sk));
+}
+
+/**
+ * apparmor_socket_accept - check perms before accepting a new connection.
+ *
+ * Note: while @newsock is created and has some information, the accept
+ * has not been done.
+ */
+static int apparmor_socket_accept(struct socket *sock, struct socket *newsock)
+{
+ AA_BUG(!sock);
+ AA_BUG(!sock->sk);
+ AA_BUG(!newsock);
+ AA_BUG(in_interrupt());
+
+ return af_select(sock->sk->sk_family,
+ accept_perm(sock, newsock),
+ aa_sk_perm(OP_ACCEPT, AA_MAY_ACCEPT, sock->sk));
+}
+
+static int aa_sock_msg_perm(const char *op, u32 request, struct socket *sock,
+ struct msghdr *msg, int size)
+{
+ AA_BUG(!sock);
+ AA_BUG(!sock->sk);
+ AA_BUG(!msg);
+ AA_BUG(in_interrupt());
+
+ return af_select(sock->sk->sk_family,
+ msg_perm(op, request, sock, msg, size),
+ aa_sk_perm(op, request, sock->sk));
+}
+
+/**
+ * apparmor_socket_sendmsg - check perms before sending msg to another socket
+ */
+static int apparmor_socket_sendmsg(struct socket *sock,
+ struct msghdr *msg, int size)
+{
+ return aa_sock_msg_perm(OP_SENDMSG, AA_MAY_SEND, sock, msg, size);
+}
+
+/**
+ * apparmor_socket_recvmsg - check perms before receiving a message
+ */
+static int apparmor_socket_recvmsg(struct socket *sock,
+ struct msghdr *msg, int size, int flags)
+{
+ return aa_sock_msg_perm(OP_RECVMSG, AA_MAY_RECEIVE, sock, msg, size);
+}
+
+/* revaliation, get/set attr, shutdown */
+static int aa_sock_perm(const char *op, u32 request, struct socket *sock)
+{
+ AA_BUG(!sock);
+ AA_BUG(!sock->sk);
+ AA_BUG(in_interrupt());
+
+ return af_select(sock->sk->sk_family,
+ sock_perm(op, request, sock),
+ aa_sk_perm(op, request, sock->sk));
+}
+
+/**
+ * apparmor_socket_getsockname - check perms before getting the local address
+ */
+static int apparmor_socket_getsockname(struct socket *sock)
+{
+ return aa_sock_perm(OP_GETSOCKNAME, AA_MAY_GETATTR, sock);
+}
+
+/**
+ * apparmor_socket_getpeername - check perms before getting remote address
+ */
+static int apparmor_socket_getpeername(struct socket *sock)
+{
+ return aa_sock_perm(OP_GETPEERNAME, AA_MAY_GETATTR, sock);
+}
+
+/* revaliation, get/set attr, opt */
+static int aa_sock_opt_perm(const char *op, u32 request, struct socket *sock,
+ int level, int optname)
+{
+ AA_BUG(!sock);
+ AA_BUG(!sock->sk);
+ AA_BUG(in_interrupt());
+
+ return af_select(sock->sk->sk_family,
+ opt_perm(op, request, sock, level, optname),
+ aa_sk_perm(op, request, sock->sk));
+}
+
+/**
+ * apparmor_getsockopt - check perms before getting socket options
+ */
+static int apparmor_socket_getsockopt(struct socket *sock, int level,
+ int optname)
+{
+ return aa_sock_opt_perm(OP_GETSOCKOPT, AA_MAY_GETOPT, sock,
+ level, optname);
+}
+
+/**
+ * apparmor_setsockopt - check perms before setting socket options
+ */
+static int apparmor_socket_setsockopt(struct socket *sock, int level,
+ int optname)
+{
+ return aa_sock_opt_perm(OP_SETSOCKOPT, AA_MAY_SETOPT, sock,
+ level, optname);
+}
+
+/**
+ * apparmor_socket_shutdown - check perms before shutting down @sock conn
+ */
+static int apparmor_socket_shutdown(struct socket *sock, int how)
+{
+ return aa_sock_perm(OP_SHUTDOWN, AA_MAY_SHUTDOWN, sock);
+}
+
+#ifdef CONFIG_NETWORK_SECMARK
+/**
+ * apparmor_socket_sock_recv_skb - check perms before associating skb to sk
+ *
+ * Note: can not sleep may be called with locks held
+ *
+ * dont want protocol specific in __skb_recv_datagram()
+ * to deny an incoming connection socket_sock_rcv_skb()
+ */
+static int apparmor_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
+{
+ struct aa_sk_ctx *ctx = SK_CTX(sk);
+
+ if (!skb->secmark)
+ return 0;
+
+ return apparmor_secmark_check(ctx->label, OP_RECVMSG, AA_MAY_RECEIVE,
+ skb->secmark, sk);
+}
+#endif
+
+
+static struct aa_label *sk_peer_label(struct sock *sk)
+{
+ struct aa_sk_ctx *ctx = SK_CTX(sk);
+
+ if (ctx->peer)
+ return ctx->peer;
+
+ return ERR_PTR(-ENOPROTOOPT);
+}
+
+/**
+ * apparmor_socket_getpeersec_stream - get security context of peer
+ *
+ * Note: for tcp only valid if using ipsec or cipso on lan
+ */
+static int apparmor_socket_getpeersec_stream(struct socket *sock,
+ char __user *optval,
+ int __user *optlen,
+ unsigned int len)
+{
+ char *name;
+ int slen, error = 0;
+ struct aa_label *label;
+ struct aa_label *peer;
+
+ label = begin_current_label_crit_section();
+ peer = sk_peer_label(sock->sk);
+ if (IS_ERR(peer)) {
+ error = PTR_ERR(peer);
+ goto done;
+ }
+ slen = aa_label_asxprint(&name, labels_ns(label), peer,
+ FLAG_SHOW_MODE | FLAG_VIEW_SUBNS |
+ FLAG_HIDDEN_UNCONFINED, GFP_KERNEL);
+ /* don't include terminating \0 in slen, it breaks some apps */
+ if (slen < 0) {
+ error = -ENOMEM;
+ } else {
+ if (slen > len) {
+ error = -ERANGE;
+ } else if (copy_to_user(optval, name, slen)) {
+ error = -EFAULT;
+ goto out;
+ }
+ if (put_user(slen, optlen))
+ error = -EFAULT;
+out:
+ kfree(name);
+
+ }
+
+done:
+ end_current_label_crit_section(label);
+
+ return error;
+}
+
+/**
+ * apparmor_socket_getpeersec_dgram - get security label of packet
+ * @sock: the peer socket
+ * @skb: packet data
+ * @secid: pointer to where to put the secid of the packet
+ *
+ * Sets the netlabel socket state on sk from parent
+ */
+static int apparmor_socket_getpeersec_dgram(struct socket *sock,
+ struct sk_buff *skb, u32 *secid)
+
+{
+ /* TODO: requires secid support */
+ return -ENOPROTOOPT;
+}
+
+/**
+ * apparmor_sock_graft - Initialize newly created socket
+ * @sk: child sock
+ * @parent: parent socket
+ *
+ * Note: could set off of SOCK_CTX(parent) but need to track inode and we can
+ * just set sk security information off of current creating process label
+ * Labeling of sk for accept case - probably should be sock based
+ * instead of task, because of the case where an implicitly labeled
+ * socket is shared by different tasks.
+ */
+static void apparmor_sock_graft(struct sock *sk, struct socket *parent)
+{
+ struct aa_sk_ctx *ctx = SK_CTX(sk);
+
+ if (!ctx->label)
+ ctx->label = aa_get_current_label();
+}
+
+#ifdef CONFIG_NETWORK_SECMARK
+static int apparmor_inet_conn_request(struct sock *sk, struct sk_buff *skb,
+ struct request_sock *req)
+{
+ struct aa_sk_ctx *ctx = SK_CTX(sk);
+
+ if (!skb->secmark)
+ return 0;
+
+ return apparmor_secmark_check(ctx->label, OP_CONNECT, AA_MAY_CONNECT,
+ skb->secmark, sk);
+}
+#endif
+
+/*
+ * The cred blob is a pointer to, not an instance of, an aa_label.
+ */
+struct lsm_blob_sizes apparmor_blob_sizes __lsm_ro_after_init = {
+ .lbs_cred = sizeof(struct aa_label *),
+ .lbs_file = sizeof(struct aa_file_ctx),
+ .lbs_task = sizeof(struct aa_task_ctx),
+};
+
+static struct security_hook_list apparmor_hooks[] __lsm_ro_after_init = {
+ LSM_HOOK_INIT(ptrace_access_check, apparmor_ptrace_access_check),
+ LSM_HOOK_INIT(ptrace_traceme, apparmor_ptrace_traceme),
+ LSM_HOOK_INIT(capget, apparmor_capget),
+ LSM_HOOK_INIT(capable, apparmor_capable),
+
+ LSM_HOOK_INIT(sb_mount, apparmor_sb_mount),
+ LSM_HOOK_INIT(sb_umount, apparmor_sb_umount),
+ LSM_HOOK_INIT(sb_pivotroot, apparmor_sb_pivotroot),
+
+ LSM_HOOK_INIT(path_link, apparmor_path_link),
+ LSM_HOOK_INIT(path_unlink, apparmor_path_unlink),
+ LSM_HOOK_INIT(path_symlink, apparmor_path_symlink),
+ LSM_HOOK_INIT(path_mkdir, apparmor_path_mkdir),
+ LSM_HOOK_INIT(path_rmdir, apparmor_path_rmdir),
+ LSM_HOOK_INIT(path_mknod, apparmor_path_mknod),
+ LSM_HOOK_INIT(path_rename, apparmor_path_rename),
+ LSM_HOOK_INIT(path_chmod, apparmor_path_chmod),
+ LSM_HOOK_INIT(path_chown, apparmor_path_chown),
+ LSM_HOOK_INIT(path_truncate, apparmor_path_truncate),
+ LSM_HOOK_INIT(inode_getattr, apparmor_inode_getattr),
+
+ LSM_HOOK_INIT(file_open, apparmor_file_open),
+ LSM_HOOK_INIT(file_receive, apparmor_file_receive),
+ LSM_HOOK_INIT(file_permission, apparmor_file_permission),
+ LSM_HOOK_INIT(file_alloc_security, apparmor_file_alloc_security),
+ LSM_HOOK_INIT(file_free_security, apparmor_file_free_security),
+ LSM_HOOK_INIT(mmap_file, apparmor_mmap_file),
+ LSM_HOOK_INIT(file_mprotect, apparmor_file_mprotect),
+ LSM_HOOK_INIT(file_lock, apparmor_file_lock),
+
+ LSM_HOOK_INIT(getprocattr, apparmor_getprocattr),
+ LSM_HOOK_INIT(setprocattr, apparmor_setprocattr),
+
+ LSM_HOOK_INIT(sk_alloc_security, apparmor_sk_alloc_security),
+ LSM_HOOK_INIT(sk_free_security, apparmor_sk_free_security),
+ LSM_HOOK_INIT(sk_clone_security, apparmor_sk_clone_security),
+
+ LSM_HOOK_INIT(socket_create, apparmor_socket_create),
+ LSM_HOOK_INIT(socket_post_create, apparmor_socket_post_create),
+ LSM_HOOK_INIT(socket_bind, apparmor_socket_bind),
+ LSM_HOOK_INIT(socket_connect, apparmor_socket_connect),
+ LSM_HOOK_INIT(socket_listen, apparmor_socket_listen),
+ LSM_HOOK_INIT(socket_accept, apparmor_socket_accept),
+ LSM_HOOK_INIT(socket_sendmsg, apparmor_socket_sendmsg),
+ LSM_HOOK_INIT(socket_recvmsg, apparmor_socket_recvmsg),
+ LSM_HOOK_INIT(socket_getsockname, apparmor_socket_getsockname),
+ LSM_HOOK_INIT(socket_getpeername, apparmor_socket_getpeername),
+ LSM_HOOK_INIT(socket_getsockopt, apparmor_socket_getsockopt),
+ LSM_HOOK_INIT(socket_setsockopt, apparmor_socket_setsockopt),
+ LSM_HOOK_INIT(socket_shutdown, apparmor_socket_shutdown),
+#ifdef CONFIG_NETWORK_SECMARK
+ LSM_HOOK_INIT(socket_sock_rcv_skb, apparmor_socket_sock_rcv_skb),
+#endif
+ LSM_HOOK_INIT(socket_getpeersec_stream,
+ apparmor_socket_getpeersec_stream),
+ LSM_HOOK_INIT(socket_getpeersec_dgram,
+ apparmor_socket_getpeersec_dgram),
+ LSM_HOOK_INIT(sock_graft, apparmor_sock_graft),
+#ifdef CONFIG_NETWORK_SECMARK
+ LSM_HOOK_INIT(inet_conn_request, apparmor_inet_conn_request),
+#endif
+
+ LSM_HOOK_INIT(cred_alloc_blank, apparmor_cred_alloc_blank),
+ LSM_HOOK_INIT(cred_free, apparmor_cred_free),
+ LSM_HOOK_INIT(cred_prepare, apparmor_cred_prepare),
+ LSM_HOOK_INIT(cred_transfer, apparmor_cred_transfer),
+
+ LSM_HOOK_INIT(bprm_creds_for_exec, apparmor_bprm_creds_for_exec),
+ LSM_HOOK_INIT(bprm_committing_creds, apparmor_bprm_committing_creds),
+ LSM_HOOK_INIT(bprm_committed_creds, apparmor_bprm_committed_creds),
+
+ LSM_HOOK_INIT(task_free, apparmor_task_free),
+ LSM_HOOK_INIT(task_alloc, apparmor_task_alloc),
+ LSM_HOOK_INIT(task_getsecid, apparmor_task_getsecid),
+ LSM_HOOK_INIT(task_setrlimit, apparmor_task_setrlimit),
+ LSM_HOOK_INIT(task_kill, apparmor_task_kill),
+
+#ifdef CONFIG_AUDIT
+ LSM_HOOK_INIT(audit_rule_init, aa_audit_rule_init),
+ LSM_HOOK_INIT(audit_rule_known, aa_audit_rule_known),
+ LSM_HOOK_INIT(audit_rule_match, aa_audit_rule_match),
+ LSM_HOOK_INIT(audit_rule_free, aa_audit_rule_free),
+#endif
+
+ LSM_HOOK_INIT(secid_to_secctx, apparmor_secid_to_secctx),
+ LSM_HOOK_INIT(secctx_to_secid, apparmor_secctx_to_secid),
+ LSM_HOOK_INIT(release_secctx, apparmor_release_secctx),
+};
+
+/*
+ * AppArmor sysfs module parameters
+ */
+
+static int param_set_aabool(const char *val, const struct kernel_param *kp);
+static int param_get_aabool(char *buffer, const struct kernel_param *kp);
+#define param_check_aabool param_check_bool
+static const struct kernel_param_ops param_ops_aabool = {
+ .flags = KERNEL_PARAM_OPS_FL_NOARG,
+ .set = param_set_aabool,
+ .get = param_get_aabool
+};
+
+static int param_set_aauint(const char *val, const struct kernel_param *kp);
+static int param_get_aauint(char *buffer, const struct kernel_param *kp);
+#define param_check_aauint param_check_uint
+static const struct kernel_param_ops param_ops_aauint = {
+ .set = param_set_aauint,
+ .get = param_get_aauint
+};
+
+static int param_set_aacompressionlevel(const char *val,
+ const struct kernel_param *kp);
+static int param_get_aacompressionlevel(char *buffer,
+ const struct kernel_param *kp);
+#define param_check_aacompressionlevel param_check_int
+static const struct kernel_param_ops param_ops_aacompressionlevel = {
+ .set = param_set_aacompressionlevel,
+ .get = param_get_aacompressionlevel
+};
+
+static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp);
+static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp);
+#define param_check_aalockpolicy param_check_bool
+static const struct kernel_param_ops param_ops_aalockpolicy = {
+ .flags = KERNEL_PARAM_OPS_FL_NOARG,
+ .set = param_set_aalockpolicy,
+ .get = param_get_aalockpolicy
+};
+
+static int param_set_audit(const char *val, const struct kernel_param *kp);
+static int param_get_audit(char *buffer, const struct kernel_param *kp);
+
+static int param_set_mode(const char *val, const struct kernel_param *kp);
+static int param_get_mode(char *buffer, const struct kernel_param *kp);
+
+/* Flag values, also controllable via /sys/module/apparmor/parameters
+ * We define special types as we want to do additional mediation.
+ */
+
+/* AppArmor global enforcement switch - complain, enforce, kill */
+enum profile_mode aa_g_profile_mode = APPARMOR_ENFORCE;
+module_param_call(mode, param_set_mode, param_get_mode,
+ &aa_g_profile_mode, S_IRUSR | S_IWUSR);
+
+/* whether policy verification hashing is enabled */
+bool aa_g_hash_policy = IS_ENABLED(CONFIG_SECURITY_APPARMOR_HASH_DEFAULT);
+#ifdef CONFIG_SECURITY_APPARMOR_HASH
+module_param_named(hash_policy, aa_g_hash_policy, aabool, S_IRUSR | S_IWUSR);
+#endif
+
+/* policy loaddata compression level */
+int aa_g_rawdata_compression_level = Z_DEFAULT_COMPRESSION;
+module_param_named(rawdata_compression_level, aa_g_rawdata_compression_level,
+ aacompressionlevel, 0400);
+
+/* Debug mode */
+bool aa_g_debug = IS_ENABLED(CONFIG_SECURITY_APPARMOR_DEBUG_MESSAGES);
+module_param_named(debug, aa_g_debug, aabool, S_IRUSR | S_IWUSR);
+
+/* Audit mode */
+enum audit_mode aa_g_audit;
+module_param_call(audit, param_set_audit, param_get_audit,
+ &aa_g_audit, S_IRUSR | S_IWUSR);
+
+/* Determines if audit header is included in audited messages. This
+ * provides more context if the audit daemon is not running
+ */
+bool aa_g_audit_header = true;
+module_param_named(audit_header, aa_g_audit_header, aabool,
+ S_IRUSR | S_IWUSR);
+
+/* lock out loading/removal of policy
+ * TODO: add in at boot loading of policy, which is the only way to
+ * load policy, if lock_policy is set
+ */
+bool aa_g_lock_policy;
+module_param_named(lock_policy, aa_g_lock_policy, aalockpolicy,
+ S_IRUSR | S_IWUSR);
+
+/* Syscall logging mode */
+bool aa_g_logsyscall;
+module_param_named(logsyscall, aa_g_logsyscall, aabool, S_IRUSR | S_IWUSR);
+
+/* Maximum pathname length before accesses will start getting rejected */
+unsigned int aa_g_path_max = 2 * PATH_MAX;
+module_param_named(path_max, aa_g_path_max, aauint, S_IRUSR);
+
+/* Determines how paranoid loading of policy is and how much verification
+ * on the loaded policy is done.
+ * DEPRECATED: read only as strict checking of load is always done now
+ * that none root users (user namespaces) can load policy.
+ */
+bool aa_g_paranoid_load = true;
+module_param_named(paranoid_load, aa_g_paranoid_load, aabool, S_IRUGO);
+
+static int param_get_aaintbool(char *buffer, const struct kernel_param *kp);
+static int param_set_aaintbool(const char *val, const struct kernel_param *kp);
+#define param_check_aaintbool param_check_int
+static const struct kernel_param_ops param_ops_aaintbool = {
+ .set = param_set_aaintbool,
+ .get = param_get_aaintbool
+};
+/* Boot time disable flag */
+static int apparmor_enabled __lsm_ro_after_init = 1;
+module_param_named(enabled, apparmor_enabled, aaintbool, 0444);
+
+static int __init apparmor_enabled_setup(char *str)
+{
+ unsigned long enabled;
+ int error = kstrtoul(str, 0, &enabled);
+ if (!error)
+ apparmor_enabled = enabled ? 1 : 0;
+ return 1;
+}
+
+__setup("apparmor=", apparmor_enabled_setup);
+
+/* set global flag turning off the ability to load policy */
+static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp)
+{
+ if (!apparmor_enabled)
+ return -EINVAL;
+ if (apparmor_initialized && !policy_admin_capable(NULL))
+ return -EPERM;
+ return param_set_bool(val, kp);
+}
+
+static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp)
+{
+ if (!apparmor_enabled)
+ return -EINVAL;
+ if (apparmor_initialized && !policy_view_capable(NULL))
+ return -EPERM;
+ return param_get_bool(buffer, kp);
+}
+
+static int param_set_aabool(const char *val, const struct kernel_param *kp)
+{
+ if (!apparmor_enabled)
+ return -EINVAL;
+ if (apparmor_initialized && !policy_admin_capable(NULL))
+ return -EPERM;
+ return param_set_bool(val, kp);
+}
+
+static int param_get_aabool(char *buffer, const struct kernel_param *kp)
+{
+ if (!apparmor_enabled)
+ return -EINVAL;
+ if (apparmor_initialized && !policy_view_capable(NULL))
+ return -EPERM;
+ return param_get_bool(buffer, kp);
+}
+
+static int param_set_aauint(const char *val, const struct kernel_param *kp)
+{
+ int error;
+
+ if (!apparmor_enabled)
+ return -EINVAL;
+ /* file is ro but enforce 2nd line check */
+ if (apparmor_initialized)
+ return -EPERM;
+
+ error = param_set_uint(val, kp);
+ aa_g_path_max = max_t(uint32_t, aa_g_path_max, sizeof(union aa_buffer));
+ pr_info("AppArmor: buffer size set to %d bytes\n", aa_g_path_max);
+
+ return error;
+}
+
+static int param_get_aauint(char *buffer, const struct kernel_param *kp)
+{
+ if (!apparmor_enabled)
+ return -EINVAL;
+ if (apparmor_initialized && !policy_view_capable(NULL))
+ return -EPERM;
+ return param_get_uint(buffer, kp);
+}
+
+/* Can only be set before AppArmor is initialized (i.e. on boot cmdline). */
+static int param_set_aaintbool(const char *val, const struct kernel_param *kp)
+{
+ struct kernel_param kp_local;
+ bool value;
+ int error;
+
+ if (apparmor_initialized)
+ return -EPERM;
+
+ /* Create local copy, with arg pointing to bool type. */
+ value = !!*((int *)kp->arg);
+ memcpy(&kp_local, kp, sizeof(kp_local));
+ kp_local.arg = &value;
+
+ error = param_set_bool(val, &kp_local);
+ if (!error)
+ *((int *)kp->arg) = *((bool *)kp_local.arg);
+ return error;
+}
+
+/*
+ * To avoid changing /sys/module/apparmor/parameters/enabled from Y/N to
+ * 1/0, this converts the "int that is actually bool" back to bool for
+ * display in the /sys filesystem, while keeping it "int" for the LSM
+ * infrastructure.
+ */
+static int param_get_aaintbool(char *buffer, const struct kernel_param *kp)
+{
+ struct kernel_param kp_local;
+ bool value;
+
+ /* Create local copy, with arg pointing to bool type. */
+ value = !!*((int *)kp->arg);
+ memcpy(&kp_local, kp, sizeof(kp_local));
+ kp_local.arg = &value;
+
+ return param_get_bool(buffer, &kp_local);
+}
+
+static int param_set_aacompressionlevel(const char *val,
+ const struct kernel_param *kp)
+{
+ int error;
+
+ if (!apparmor_enabled)
+ return -EINVAL;
+ if (apparmor_initialized)
+ return -EPERM;
+
+ error = param_set_int(val, kp);
+
+ aa_g_rawdata_compression_level = clamp(aa_g_rawdata_compression_level,
+ Z_NO_COMPRESSION,
+ Z_BEST_COMPRESSION);
+ pr_info("AppArmor: policy rawdata compression level set to %u\n",
+ aa_g_rawdata_compression_level);
+
+ return error;
+}
+
+static int param_get_aacompressionlevel(char *buffer,
+ const struct kernel_param *kp)
+{
+ if (!apparmor_enabled)
+ return -EINVAL;
+ if (apparmor_initialized && !policy_view_capable(NULL))
+ return -EPERM;
+ return param_get_int(buffer, kp);
+}
+
+static int param_get_audit(char *buffer, const struct kernel_param *kp)
+{
+ if (!apparmor_enabled)
+ return -EINVAL;
+ if (apparmor_initialized && !policy_view_capable(NULL))
+ return -EPERM;
+ return sprintf(buffer, "%s", audit_mode_names[aa_g_audit]);
+}
+
+static int param_set_audit(const char *val, const struct kernel_param *kp)
+{
+ int i;
+
+ if (!apparmor_enabled)
+ return -EINVAL;
+ if (!val)
+ return -EINVAL;
+ if (apparmor_initialized && !policy_admin_capable(NULL))
+ return -EPERM;
+
+ i = match_string(audit_mode_names, AUDIT_MAX_INDEX, val);
+ if (i < 0)
+ return -EINVAL;
+
+ aa_g_audit = i;
+ return 0;
+}
+
+static int param_get_mode(char *buffer, const struct kernel_param *kp)
+{
+ if (!apparmor_enabled)
+ return -EINVAL;
+ if (apparmor_initialized && !policy_view_capable(NULL))
+ return -EPERM;
+
+ return sprintf(buffer, "%s", aa_profile_mode_names[aa_g_profile_mode]);
+}
+
+static int param_set_mode(const char *val, const struct kernel_param *kp)
+{
+ int i;
+
+ if (!apparmor_enabled)
+ return -EINVAL;
+ if (!val)
+ return -EINVAL;
+ if (apparmor_initialized && !policy_admin_capable(NULL))
+ return -EPERM;
+
+ i = match_string(aa_profile_mode_names, APPARMOR_MODE_NAMES_MAX_INDEX,
+ val);
+ if (i < 0)
+ return -EINVAL;
+
+ aa_g_profile_mode = i;
+ return 0;
+}
+
+char *aa_get_buffer(bool in_atomic)
+{
+ union aa_buffer *aa_buf;
+ bool try_again = true;
+ gfp_t flags = (GFP_KERNEL | __GFP_RETRY_MAYFAIL | __GFP_NOWARN);
+
+retry:
+ spin_lock(&aa_buffers_lock);
+ if (buffer_count > reserve_count ||
+ (in_atomic && !list_empty(&aa_global_buffers))) {
+ aa_buf = list_first_entry(&aa_global_buffers, union aa_buffer,
+ list);
+ list_del(&aa_buf->list);
+ buffer_count--;
+ spin_unlock(&aa_buffers_lock);
+ return &aa_buf->buffer[0];
+ }
+ if (in_atomic) {
+ /*
+ * out of reserve buffers and in atomic context so increase
+ * how many buffers to keep in reserve
+ */
+ reserve_count++;
+ flags = GFP_ATOMIC;
+ }
+ spin_unlock(&aa_buffers_lock);
+
+ if (!in_atomic)
+ might_sleep();
+ aa_buf = kmalloc(aa_g_path_max, flags);
+ if (!aa_buf) {
+ if (try_again) {
+ try_again = false;
+ goto retry;
+ }
+ pr_warn_once("AppArmor: Failed to allocate a memory buffer.\n");
+ return NULL;
+ }
+ return &aa_buf->buffer[0];
+}
+
+void aa_put_buffer(char *buf)
+{
+ union aa_buffer *aa_buf;
+
+ if (!buf)
+ return;
+ aa_buf = container_of(buf, union aa_buffer, buffer[0]);
+
+ spin_lock(&aa_buffers_lock);
+ list_add(&aa_buf->list, &aa_global_buffers);
+ buffer_count++;
+ spin_unlock(&aa_buffers_lock);
+}
+
+/*
+ * AppArmor init functions
+ */
+
+/**
+ * set_init_ctx - set a task context and profile on the first task.
+ *
+ * TODO: allow setting an alternate profile than unconfined
+ */
+static int __init set_init_ctx(void)
+{
+ struct cred *cred = (__force struct cred *)current->real_cred;
+
+ set_cred_label(cred, aa_get_label(ns_unconfined(root_ns)));
+
+ return 0;
+}
+
+static void destroy_buffers(void)
+{
+ union aa_buffer *aa_buf;
+
+ spin_lock(&aa_buffers_lock);
+ while (!list_empty(&aa_global_buffers)) {
+ aa_buf = list_first_entry(&aa_global_buffers, union aa_buffer,
+ list);
+ list_del(&aa_buf->list);
+ spin_unlock(&aa_buffers_lock);
+ kfree(aa_buf);
+ spin_lock(&aa_buffers_lock);
+ }
+ spin_unlock(&aa_buffers_lock);
+}
+
+static int __init alloc_buffers(void)
+{
+ union aa_buffer *aa_buf;
+ int i, num;
+
+ /*
+ * A function may require two buffers at once. Usually the buffers are
+ * used for a short period of time and are shared. On UP kernel buffers
+ * two should be enough, with more CPUs it is possible that more
+ * buffers will be used simultaneously. The preallocated pool may grow.
+ * This preallocation has also the side-effect that AppArmor will be
+ * disabled early at boot if aa_g_path_max is extremly high.
+ */
+ if (num_online_cpus() > 1)
+ num = 4 + RESERVE_COUNT;
+ else
+ num = 2 + RESERVE_COUNT;
+
+ for (i = 0; i < num; i++) {
+
+ aa_buf = kmalloc(aa_g_path_max, GFP_KERNEL |
+ __GFP_RETRY_MAYFAIL | __GFP_NOWARN);
+ if (!aa_buf) {
+ destroy_buffers();
+ return -ENOMEM;
+ }
+ aa_put_buffer(&aa_buf->buffer[0]);
+ }
+ return 0;
+}
+
+#ifdef CONFIG_SYSCTL
+static int apparmor_dointvec(struct ctl_table *table, int write,
+ void *buffer, size_t *lenp, loff_t *ppos)
+{
+ if (!policy_admin_capable(NULL))
+ return -EPERM;
+ if (!apparmor_enabled)
+ return -EINVAL;
+
+ return proc_dointvec(table, write, buffer, lenp, ppos);
+}
+
+static struct ctl_path apparmor_sysctl_path[] = {
+ { .procname = "kernel", },
+ { }
+};
+
+static struct ctl_table apparmor_sysctl_table[] = {
+ {
+ .procname = "unprivileged_userns_apparmor_policy",
+ .data = &unprivileged_userns_apparmor_policy,
+ .maxlen = sizeof(int),
+ .mode = 0600,
+ .proc_handler = apparmor_dointvec,
+ },
+ { }
+};
+
+static int __init apparmor_init_sysctl(void)
+{
+ return register_sysctl_paths(apparmor_sysctl_path,
+ apparmor_sysctl_table) ? 0 : -ENOMEM;
+}
+#else
+static inline int apparmor_init_sysctl(void)
+{
+ return 0;
+}
+#endif /* CONFIG_SYSCTL */
+
+#if defined(CONFIG_NETFILTER) && defined(CONFIG_NETWORK_SECMARK)
+static unsigned int apparmor_ip_postroute(void *priv,
+ struct sk_buff *skb,
+ const struct nf_hook_state *state)
+{
+ struct aa_sk_ctx *ctx;
+ struct sock *sk;
+
+ if (!skb->secmark)
+ return NF_ACCEPT;
+
+ sk = skb_to_full_sk(skb);
+ if (sk == NULL)
+ return NF_ACCEPT;
+
+ ctx = SK_CTX(sk);
+ if (!apparmor_secmark_check(ctx->label, OP_SENDMSG, AA_MAY_SEND,
+ skb->secmark, sk))
+ return NF_ACCEPT;
+
+ return NF_DROP_ERR(-ECONNREFUSED);
+
+}
+
+static unsigned int apparmor_ipv4_postroute(void *priv,
+ struct sk_buff *skb,
+ const struct nf_hook_state *state)
+{
+ return apparmor_ip_postroute(priv, skb, state);
+}
+
+#if IS_ENABLED(CONFIG_IPV6)
+static unsigned int apparmor_ipv6_postroute(void *priv,
+ struct sk_buff *skb,
+ const struct nf_hook_state *state)
+{
+ return apparmor_ip_postroute(priv, skb, state);
+}
+#endif
+
+static const struct nf_hook_ops apparmor_nf_ops[] = {
+ {
+ .hook = apparmor_ipv4_postroute,
+ .pf = NFPROTO_IPV4,
+ .hooknum = NF_INET_POST_ROUTING,
+ .priority = NF_IP_PRI_SELINUX_FIRST,
+ },
+#if IS_ENABLED(CONFIG_IPV6)
+ {
+ .hook = apparmor_ipv6_postroute,
+ .pf = NFPROTO_IPV6,
+ .hooknum = NF_INET_POST_ROUTING,
+ .priority = NF_IP6_PRI_SELINUX_FIRST,
+ },
+#endif
+};
+
+static int __net_init apparmor_nf_register(struct net *net)
+{
+ int ret;
+
+ ret = nf_register_net_hooks(net, apparmor_nf_ops,
+ ARRAY_SIZE(apparmor_nf_ops));
+ return ret;
+}
+
+static void __net_exit apparmor_nf_unregister(struct net *net)
+{
+ nf_unregister_net_hooks(net, apparmor_nf_ops,
+ ARRAY_SIZE(apparmor_nf_ops));
+}
+
+static struct pernet_operations apparmor_net_ops = {
+ .init = apparmor_nf_register,
+ .exit = apparmor_nf_unregister,
+};
+
+static int __init apparmor_nf_ip_init(void)
+{
+ int err;
+
+ if (!apparmor_enabled)
+ return 0;
+
+ err = register_pernet_subsys(&apparmor_net_ops);
+ if (err)
+ panic("Apparmor: register_pernet_subsys: error %d\n", err);
+
+ return 0;
+}
+__initcall(apparmor_nf_ip_init);
+#endif
+
+static int __init apparmor_init(void)
+{
+ int error;
+
+ aa_secids_init();
+
+ error = aa_setup_dfa_engine();
+ if (error) {
+ AA_ERROR("Unable to setup dfa engine\n");
+ goto alloc_out;
+ }
+
+ error = aa_alloc_root_ns();
+ if (error) {
+ AA_ERROR("Unable to allocate default profile namespace\n");
+ goto alloc_out;
+ }
+
+ error = apparmor_init_sysctl();
+ if (error) {
+ AA_ERROR("Unable to register sysctls\n");
+ goto alloc_out;
+
+ }
+
+ error = alloc_buffers();
+ if (error) {
+ AA_ERROR("Unable to allocate work buffers\n");
+ goto alloc_out;
+ }
+
+ error = set_init_ctx();
+ if (error) {
+ AA_ERROR("Failed to set context on init task\n");
+ aa_free_root_ns();
+ goto buffers_out;
+ }
+ security_add_hooks(apparmor_hooks, ARRAY_SIZE(apparmor_hooks),
+ "apparmor");
+
+ /* Report that AppArmor successfully initialized */
+ apparmor_initialized = 1;
+ if (aa_g_profile_mode == APPARMOR_COMPLAIN)
+ aa_info_message("AppArmor initialized: complain mode enabled");
+ else if (aa_g_profile_mode == APPARMOR_KILL)
+ aa_info_message("AppArmor initialized: kill mode enabled");
+ else
+ aa_info_message("AppArmor initialized");
+
+ return error;
+
+buffers_out:
+ destroy_buffers();
+alloc_out:
+ aa_destroy_aafs();
+ aa_teardown_dfa_engine();
+
+ apparmor_enabled = false;
+ return error;
+}
+
+DEFINE_LSM(apparmor) = {
+ .name = "apparmor",
+ .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
+ .enabled = &apparmor_enabled,
+ .blobs = &apparmor_blob_sizes,
+ .init = apparmor_init,
+};