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- // SPDX-License-Identifier: GPL-2.0-or-later
- /* Common capabilities, needed by capability.o.
- */
- #include <linux/capability.h>
- #include <linux/audit.h>
- #include <linux/init.h>
- #include <linux/kernel.h>
- #include <linux/lsm_hooks.h>
- #include <linux/file.h>
- #include <linux/mm.h>
- #include <linux/mman.h>
- #include <linux/pagemap.h>
- #include <linux/swap.h>
- #include <linux/skbuff.h>
- #include <linux/netlink.h>
- #include <linux/ptrace.h>
- #include <linux/xattr.h>
- #include <linux/hugetlb.h>
- #include <linux/mount.h>
- #include <linux/sched.h>
- #include <linux/prctl.h>
- #include <linux/securebits.h>
- #include <linux/user_namespace.h>
- #include <linux/binfmts.h>
- #include <linux/personality.h>
- #include <linux/mnt_idmapping.h>
- #include <uapi/linux/lsm.h>
- /*
- * If a non-root user executes a setuid-root binary in
- * !secure(SECURE_NOROOT) mode, then we raise capabilities.
- * However if fE is also set, then the intent is for only
- * the file capabilities to be applied, and the setuid-root
- * bit is left on either to change the uid (plausible) or
- * to get full privilege on a kernel without file capabilities
- * support. So in that case we do not raise capabilities.
- *
- * Warn if that happens, once per boot.
- */
- static void warn_setuid_and_fcaps_mixed(const char *fname)
- {
- static int warned;
- if (!warned) {
- printk(KERN_INFO "warning: `%s' has both setuid-root and"
- " effective capabilities. Therefore not raising all"
- " capabilities.\n", fname);
- warned = 1;
- }
- }
- /**
- * cap_capable - Determine whether a task has a particular effective capability
- * @cred: The credentials to use
- * @targ_ns: The user namespace in which we need the capability
- * @cap: The capability to check for
- * @opts: Bitmask of options defined in include/linux/security.h
- *
- * Determine whether the nominated task has the specified capability amongst
- * its effective set, returning 0 if it does, -ve if it does not.
- *
- * NOTE WELL: cap_has_capability() cannot be used like the kernel's capable()
- * and has_capability() functions. That is, it has the reverse semantics:
- * cap_has_capability() returns 0 when a task has a capability, but the
- * kernel's capable() and has_capability() returns 1 for this case.
- */
- int cap_capable(const struct cred *cred, struct user_namespace *targ_ns,
- int cap, unsigned int opts)
- {
- struct user_namespace *ns = targ_ns;
- /* See if cred has the capability in the target user namespace
- * by examining the target user namespace and all of the target
- * user namespace's parents.
- */
- for (;;) {
- /* Do we have the necessary capabilities? */
- if (ns == cred->user_ns)
- return cap_raised(cred->cap_effective, cap) ? 0 : -EPERM;
- /*
- * If we're already at a lower level than we're looking for,
- * we're done searching.
- */
- if (ns->level <= cred->user_ns->level)
- return -EPERM;
- /*
- * The owner of the user namespace in the parent of the
- * user namespace has all caps.
- */
- if ((ns->parent == cred->user_ns) && uid_eq(ns->owner, cred->euid))
- return 0;
- /*
- * If you have a capability in a parent user ns, then you have
- * it over all children user namespaces as well.
- */
- ns = ns->parent;
- }
- /* We never get here */
- }
- /**
- * cap_settime - Determine whether the current process may set the system clock
- * @ts: The time to set
- * @tz: The timezone to set
- *
- * Determine whether the current process may set the system clock and timezone
- * information, returning 0 if permission granted, -ve if denied.
- */
- int cap_settime(const struct timespec64 *ts, const struct timezone *tz)
- {
- if (!capable(CAP_SYS_TIME))
- return -EPERM;
- return 0;
- }
- /**
- * cap_ptrace_access_check - Determine whether the current process may access
- * another
- * @child: The process to be accessed
- * @mode: The mode of attachment.
- *
- * If we are in the same or an ancestor user_ns and have all the target
- * task's capabilities, then ptrace access is allowed.
- * If we have the ptrace capability to the target user_ns, then ptrace
- * access is allowed.
- * Else denied.
- *
- * Determine whether a process may access another, returning 0 if permission
- * granted, -ve if denied.
- */
- int cap_ptrace_access_check(struct task_struct *child, unsigned int mode)
- {
- int ret = 0;
- const struct cred *cred, *child_cred;
- const kernel_cap_t *caller_caps;
- rcu_read_lock();
- cred = current_cred();
- child_cred = __task_cred(child);
- if (mode & PTRACE_MODE_FSCREDS)
- caller_caps = &cred->cap_effective;
- else
- caller_caps = &cred->cap_permitted;
- if (cred->user_ns == child_cred->user_ns &&
- cap_issubset(child_cred->cap_permitted, *caller_caps))
- goto out;
- if (ns_capable(child_cred->user_ns, CAP_SYS_PTRACE))
- goto out;
- ret = -EPERM;
- out:
- rcu_read_unlock();
- return ret;
- }
- /**
- * cap_ptrace_traceme - Determine whether another process may trace the current
- * @parent: The task proposed to be the tracer
- *
- * If parent is in the same or an ancestor user_ns and has all current's
- * capabilities, then ptrace access is allowed.
- * If parent has the ptrace capability to current's user_ns, then ptrace
- * access is allowed.
- * Else denied.
- *
- * Determine whether the nominated task is permitted to trace the current
- * process, returning 0 if permission is granted, -ve if denied.
- */
- int cap_ptrace_traceme(struct task_struct *parent)
- {
- int ret = 0;
- const struct cred *cred, *child_cred;
- rcu_read_lock();
- cred = __task_cred(parent);
- child_cred = current_cred();
- if (cred->user_ns == child_cred->user_ns &&
- cap_issubset(child_cred->cap_permitted, cred->cap_permitted))
- goto out;
- if (has_ns_capability(parent, child_cred->user_ns, CAP_SYS_PTRACE))
- goto out;
- ret = -EPERM;
- out:
- rcu_read_unlock();
- return ret;
- }
- /**
- * cap_capget - Retrieve a task's capability sets
- * @target: The task from which to retrieve the capability sets
- * @effective: The place to record the effective set
- * @inheritable: The place to record the inheritable set
- * @permitted: The place to record the permitted set
- *
- * This function retrieves the capabilities of the nominated task and returns
- * them to the caller.
- */
- int cap_capget(const struct task_struct *target, kernel_cap_t *effective,
- kernel_cap_t *inheritable, kernel_cap_t *permitted)
- {
- const struct cred *cred;
- /* Derived from kernel/capability.c:sys_capget. */
- rcu_read_lock();
- cred = __task_cred(target);
- *effective = cred->cap_effective;
- *inheritable = cred->cap_inheritable;
- *permitted = cred->cap_permitted;
- rcu_read_unlock();
- return 0;
- }
- /*
- * Determine whether the inheritable capabilities are limited to the old
- * permitted set. Returns 1 if they are limited, 0 if they are not.
- */
- static inline int cap_inh_is_capped(void)
- {
- /* they are so limited unless the current task has the CAP_SETPCAP
- * capability
- */
- if (cap_capable(current_cred(), current_cred()->user_ns,
- CAP_SETPCAP, CAP_OPT_NONE) == 0)
- return 0;
- return 1;
- }
- /**
- * cap_capset - Validate and apply proposed changes to current's capabilities
- * @new: The proposed new credentials; alterations should be made here
- * @old: The current task's current credentials
- * @effective: A pointer to the proposed new effective capabilities set
- * @inheritable: A pointer to the proposed new inheritable capabilities set
- * @permitted: A pointer to the proposed new permitted capabilities set
- *
- * This function validates and applies a proposed mass change to the current
- * process's capability sets. The changes are made to the proposed new
- * credentials, and assuming no error, will be committed by the caller of LSM.
- */
- int cap_capset(struct cred *new,
- const struct cred *old,
- const kernel_cap_t *effective,
- const kernel_cap_t *inheritable,
- const kernel_cap_t *permitted)
- {
- if (cap_inh_is_capped() &&
- !cap_issubset(*inheritable,
- cap_combine(old->cap_inheritable,
- old->cap_permitted)))
- /* incapable of using this inheritable set */
- return -EPERM;
- if (!cap_issubset(*inheritable,
- cap_combine(old->cap_inheritable,
- old->cap_bset)))
- /* no new pI capabilities outside bounding set */
- return -EPERM;
- /* verify restrictions on target's new Permitted set */
- if (!cap_issubset(*permitted, old->cap_permitted))
- return -EPERM;
- /* verify the _new_Effective_ is a subset of the _new_Permitted_ */
- if (!cap_issubset(*effective, *permitted))
- return -EPERM;
- new->cap_effective = *effective;
- new->cap_inheritable = *inheritable;
- new->cap_permitted = *permitted;
- /*
- * Mask off ambient bits that are no longer both permitted and
- * inheritable.
- */
- new->cap_ambient = cap_intersect(new->cap_ambient,
- cap_intersect(*permitted,
- *inheritable));
- if (WARN_ON(!cap_ambient_invariant_ok(new)))
- return -EINVAL;
- return 0;
- }
- /**
- * cap_inode_need_killpriv - Determine if inode change affects privileges
- * @dentry: The inode/dentry in being changed with change marked ATTR_KILL_PRIV
- *
- * Determine if an inode having a change applied that's marked ATTR_KILL_PRIV
- * affects the security markings on that inode, and if it is, should
- * inode_killpriv() be invoked or the change rejected.
- *
- * Return: 1 if security.capability has a value, meaning inode_killpriv()
- * is required, 0 otherwise, meaning inode_killpriv() is not required.
- */
- int cap_inode_need_killpriv(struct dentry *dentry)
- {
- struct inode *inode = d_backing_inode(dentry);
- int error;
- error = __vfs_getxattr(dentry, inode, XATTR_NAME_CAPS, NULL, 0);
- return error > 0;
- }
- /**
- * cap_inode_killpriv - Erase the security markings on an inode
- *
- * @idmap: idmap of the mount the inode was found from
- * @dentry: The inode/dentry to alter
- *
- * Erase the privilege-enhancing security markings on an inode.
- *
- * If the inode has been found through an idmapped mount the idmap of
- * the vfsmount must be passed through @idmap. This function will then
- * take care to map the inode according to @idmap before checking
- * permissions. On non-idmapped mounts or if permission checking is to be
- * performed on the raw inode simply pass @nop_mnt_idmap.
- *
- * Return: 0 if successful, -ve on error.
- */
- int cap_inode_killpriv(struct mnt_idmap *idmap, struct dentry *dentry)
- {
- int error;
- error = __vfs_removexattr(idmap, dentry, XATTR_NAME_CAPS);
- if (error == -EOPNOTSUPP)
- error = 0;
- return error;
- }
- static bool rootid_owns_currentns(vfsuid_t rootvfsuid)
- {
- struct user_namespace *ns;
- kuid_t kroot;
- if (!vfsuid_valid(rootvfsuid))
- return false;
- kroot = vfsuid_into_kuid(rootvfsuid);
- for (ns = current_user_ns();; ns = ns->parent) {
- if (from_kuid(ns, kroot) == 0)
- return true;
- if (ns == &init_user_ns)
- break;
- }
- return false;
- }
- static __u32 sansflags(__u32 m)
- {
- return m & ~VFS_CAP_FLAGS_EFFECTIVE;
- }
- static bool is_v2header(int size, const struct vfs_cap_data *cap)
- {
- if (size != XATTR_CAPS_SZ_2)
- return false;
- return sansflags(le32_to_cpu(cap->magic_etc)) == VFS_CAP_REVISION_2;
- }
- static bool is_v3header(int size, const struct vfs_cap_data *cap)
- {
- if (size != XATTR_CAPS_SZ_3)
- return false;
- return sansflags(le32_to_cpu(cap->magic_etc)) == VFS_CAP_REVISION_3;
- }
- /*
- * getsecurity: We are called for security.* before any attempt to read the
- * xattr from the inode itself.
- *
- * This gives us a chance to read the on-disk value and convert it. If we
- * return -EOPNOTSUPP, then vfs_getxattr() will call the i_op handler.
- *
- * Note we are not called by vfs_getxattr_alloc(), but that is only called
- * by the integrity subsystem, which really wants the unconverted values -
- * so that's good.
- */
- int cap_inode_getsecurity(struct mnt_idmap *idmap,
- struct inode *inode, const char *name, void **buffer,
- bool alloc)
- {
- int size;
- kuid_t kroot;
- vfsuid_t vfsroot;
- u32 nsmagic, magic;
- uid_t root, mappedroot;
- char *tmpbuf = NULL;
- struct vfs_cap_data *cap;
- struct vfs_ns_cap_data *nscap = NULL;
- struct dentry *dentry;
- struct user_namespace *fs_ns;
- if (strcmp(name, "capability") != 0)
- return -EOPNOTSUPP;
- dentry = d_find_any_alias(inode);
- if (!dentry)
- return -EINVAL;
- size = vfs_getxattr_alloc(idmap, dentry, XATTR_NAME_CAPS, &tmpbuf,
- sizeof(struct vfs_ns_cap_data), GFP_NOFS);
- dput(dentry);
- /* gcc11 complains if we don't check for !tmpbuf */
- if (size < 0 || !tmpbuf)
- goto out_free;
- fs_ns = inode->i_sb->s_user_ns;
- cap = (struct vfs_cap_data *) tmpbuf;
- if (is_v2header(size, cap)) {
- root = 0;
- } else if (is_v3header(size, cap)) {
- nscap = (struct vfs_ns_cap_data *) tmpbuf;
- root = le32_to_cpu(nscap->rootid);
- } else {
- size = -EINVAL;
- goto out_free;
- }
- kroot = make_kuid(fs_ns, root);
- /* If this is an idmapped mount shift the kuid. */
- vfsroot = make_vfsuid(idmap, fs_ns, kroot);
- /* If the root kuid maps to a valid uid in current ns, then return
- * this as a nscap. */
- mappedroot = from_kuid(current_user_ns(), vfsuid_into_kuid(vfsroot));
- if (mappedroot != (uid_t)-1 && mappedroot != (uid_t)0) {
- size = sizeof(struct vfs_ns_cap_data);
- if (alloc) {
- if (!nscap) {
- /* v2 -> v3 conversion */
- nscap = kzalloc(size, GFP_ATOMIC);
- if (!nscap) {
- size = -ENOMEM;
- goto out_free;
- }
- nsmagic = VFS_CAP_REVISION_3;
- magic = le32_to_cpu(cap->magic_etc);
- if (magic & VFS_CAP_FLAGS_EFFECTIVE)
- nsmagic |= VFS_CAP_FLAGS_EFFECTIVE;
- memcpy(&nscap->data, &cap->data, sizeof(__le32) * 2 * VFS_CAP_U32);
- nscap->magic_etc = cpu_to_le32(nsmagic);
- } else {
- /* use allocated v3 buffer */
- tmpbuf = NULL;
- }
- nscap->rootid = cpu_to_le32(mappedroot);
- *buffer = nscap;
- }
- goto out_free;
- }
- if (!rootid_owns_currentns(vfsroot)) {
- size = -EOVERFLOW;
- goto out_free;
- }
- /* This comes from a parent namespace. Return as a v2 capability */
- size = sizeof(struct vfs_cap_data);
- if (alloc) {
- if (nscap) {
- /* v3 -> v2 conversion */
- cap = kzalloc(size, GFP_ATOMIC);
- if (!cap) {
- size = -ENOMEM;
- goto out_free;
- }
- magic = VFS_CAP_REVISION_2;
- nsmagic = le32_to_cpu(nscap->magic_etc);
- if (nsmagic & VFS_CAP_FLAGS_EFFECTIVE)
- magic |= VFS_CAP_FLAGS_EFFECTIVE;
- memcpy(&cap->data, &nscap->data, sizeof(__le32) * 2 * VFS_CAP_U32);
- cap->magic_etc = cpu_to_le32(magic);
- } else {
- /* use unconverted v2 */
- tmpbuf = NULL;
- }
- *buffer = cap;
- }
- out_free:
- kfree(tmpbuf);
- return size;
- }
- /**
- * rootid_from_xattr - translate root uid of vfs caps
- *
- * @value: vfs caps value which may be modified by this function
- * @size: size of @ivalue
- * @task_ns: user namespace of the caller
- */
- static vfsuid_t rootid_from_xattr(const void *value, size_t size,
- struct user_namespace *task_ns)
- {
- const struct vfs_ns_cap_data *nscap = value;
- uid_t rootid = 0;
- if (size == XATTR_CAPS_SZ_3)
- rootid = le32_to_cpu(nscap->rootid);
- return VFSUIDT_INIT(make_kuid(task_ns, rootid));
- }
- static bool validheader(size_t size, const struct vfs_cap_data *cap)
- {
- return is_v2header(size, cap) || is_v3header(size, cap);
- }
- /**
- * cap_convert_nscap - check vfs caps
- *
- * @idmap: idmap of the mount the inode was found from
- * @dentry: used to retrieve inode to check permissions on
- * @ivalue: vfs caps value which may be modified by this function
- * @size: size of @ivalue
- *
- * User requested a write of security.capability. If needed, update the
- * xattr to change from v2 to v3, or to fixup the v3 rootid.
- *
- * If the inode has been found through an idmapped mount the idmap of
- * the vfsmount must be passed through @idmap. This function will then
- * take care to map the inode according to @idmap before checking
- * permissions. On non-idmapped mounts or if permission checking is to be
- * performed on the raw inode simply pass @nop_mnt_idmap.
- *
- * Return: On success, return the new size; on error, return < 0.
- */
- int cap_convert_nscap(struct mnt_idmap *idmap, struct dentry *dentry,
- const void **ivalue, size_t size)
- {
- struct vfs_ns_cap_data *nscap;
- uid_t nsrootid;
- const struct vfs_cap_data *cap = *ivalue;
- __u32 magic, nsmagic;
- struct inode *inode = d_backing_inode(dentry);
- struct user_namespace *task_ns = current_user_ns(),
- *fs_ns = inode->i_sb->s_user_ns;
- kuid_t rootid;
- vfsuid_t vfsrootid;
- size_t newsize;
- if (!*ivalue)
- return -EINVAL;
- if (!validheader(size, cap))
- return -EINVAL;
- if (!capable_wrt_inode_uidgid(idmap, inode, CAP_SETFCAP))
- return -EPERM;
- if (size == XATTR_CAPS_SZ_2 && (idmap == &nop_mnt_idmap))
- if (ns_capable(inode->i_sb->s_user_ns, CAP_SETFCAP))
- /* user is privileged, just write the v2 */
- return size;
- vfsrootid = rootid_from_xattr(*ivalue, size, task_ns);
- if (!vfsuid_valid(vfsrootid))
- return -EINVAL;
- rootid = from_vfsuid(idmap, fs_ns, vfsrootid);
- if (!uid_valid(rootid))
- return -EINVAL;
- nsrootid = from_kuid(fs_ns, rootid);
- if (nsrootid == -1)
- return -EINVAL;
- newsize = sizeof(struct vfs_ns_cap_data);
- nscap = kmalloc(newsize, GFP_ATOMIC);
- if (!nscap)
- return -ENOMEM;
- nscap->rootid = cpu_to_le32(nsrootid);
- nsmagic = VFS_CAP_REVISION_3;
- magic = le32_to_cpu(cap->magic_etc);
- if (magic & VFS_CAP_FLAGS_EFFECTIVE)
- nsmagic |= VFS_CAP_FLAGS_EFFECTIVE;
- nscap->magic_etc = cpu_to_le32(nsmagic);
- memcpy(&nscap->data, &cap->data, sizeof(__le32) * 2 * VFS_CAP_U32);
- *ivalue = nscap;
- return newsize;
- }
- /*
- * Calculate the new process capability sets from the capability sets attached
- * to a file.
- */
- static inline int bprm_caps_from_vfs_caps(struct cpu_vfs_cap_data *caps,
- struct linux_binprm *bprm,
- bool *effective,
- bool *has_fcap)
- {
- struct cred *new = bprm->cred;
- int ret = 0;
- if (caps->magic_etc & VFS_CAP_FLAGS_EFFECTIVE)
- *effective = true;
- if (caps->magic_etc & VFS_CAP_REVISION_MASK)
- *has_fcap = true;
- /*
- * pP' = (X & fP) | (pI & fI)
- * The addition of pA' is handled later.
- */
- new->cap_permitted.val =
- (new->cap_bset.val & caps->permitted.val) |
- (new->cap_inheritable.val & caps->inheritable.val);
- if (caps->permitted.val & ~new->cap_permitted.val)
- /* insufficient to execute correctly */
- ret = -EPERM;
- /*
- * For legacy apps, with no internal support for recognizing they
- * do not have enough capabilities, we return an error if they are
- * missing some "forced" (aka file-permitted) capabilities.
- */
- return *effective ? ret : 0;
- }
- /**
- * get_vfs_caps_from_disk - retrieve vfs caps from disk
- *
- * @idmap: idmap of the mount the inode was found from
- * @dentry: dentry from which @inode is retrieved
- * @cpu_caps: vfs capabilities
- *
- * Extract the on-exec-apply capability sets for an executable file.
- *
- * If the inode has been found through an idmapped mount the idmap of
- * the vfsmount must be passed through @idmap. This function will then
- * take care to map the inode according to @idmap before checking
- * permissions. On non-idmapped mounts or if permission checking is to be
- * performed on the raw inode simply pass @nop_mnt_idmap.
- */
- int get_vfs_caps_from_disk(struct mnt_idmap *idmap,
- const struct dentry *dentry,
- struct cpu_vfs_cap_data *cpu_caps)
- {
- struct inode *inode = d_backing_inode(dentry);
- __u32 magic_etc;
- int size;
- struct vfs_ns_cap_data data, *nscaps = &data;
- struct vfs_cap_data *caps = (struct vfs_cap_data *) &data;
- kuid_t rootkuid;
- vfsuid_t rootvfsuid;
- struct user_namespace *fs_ns;
- memset(cpu_caps, 0, sizeof(struct cpu_vfs_cap_data));
- if (!inode)
- return -ENODATA;
- fs_ns = inode->i_sb->s_user_ns;
- size = __vfs_getxattr((struct dentry *)dentry, inode,
- XATTR_NAME_CAPS, &data, XATTR_CAPS_SZ);
- if (size == -ENODATA || size == -EOPNOTSUPP)
- /* no data, that's ok */
- return -ENODATA;
- if (size < 0)
- return size;
- if (size < sizeof(magic_etc))
- return -EINVAL;
- cpu_caps->magic_etc = magic_etc = le32_to_cpu(caps->magic_etc);
- rootkuid = make_kuid(fs_ns, 0);
- switch (magic_etc & VFS_CAP_REVISION_MASK) {
- case VFS_CAP_REVISION_1:
- if (size != XATTR_CAPS_SZ_1)
- return -EINVAL;
- break;
- case VFS_CAP_REVISION_2:
- if (size != XATTR_CAPS_SZ_2)
- return -EINVAL;
- break;
- case VFS_CAP_REVISION_3:
- if (size != XATTR_CAPS_SZ_3)
- return -EINVAL;
- rootkuid = make_kuid(fs_ns, le32_to_cpu(nscaps->rootid));
- break;
- default:
- return -EINVAL;
- }
- rootvfsuid = make_vfsuid(idmap, fs_ns, rootkuid);
- if (!vfsuid_valid(rootvfsuid))
- return -ENODATA;
- /* Limit the caps to the mounter of the filesystem
- * or the more limited uid specified in the xattr.
- */
- if (!rootid_owns_currentns(rootvfsuid))
- return -ENODATA;
- cpu_caps->permitted.val = le32_to_cpu(caps->data[0].permitted);
- cpu_caps->inheritable.val = le32_to_cpu(caps->data[0].inheritable);
- /*
- * Rev1 had just a single 32-bit word, later expanded
- * to a second one for the high bits
- */
- if ((magic_etc & VFS_CAP_REVISION_MASK) != VFS_CAP_REVISION_1) {
- cpu_caps->permitted.val += (u64)le32_to_cpu(caps->data[1].permitted) << 32;
- cpu_caps->inheritable.val += (u64)le32_to_cpu(caps->data[1].inheritable) << 32;
- }
- cpu_caps->permitted.val &= CAP_VALID_MASK;
- cpu_caps->inheritable.val &= CAP_VALID_MASK;
- cpu_caps->rootid = vfsuid_into_kuid(rootvfsuid);
- return 0;
- }
- /*
- * Attempt to get the on-exec apply capability sets for an executable file from
- * its xattrs and, if present, apply them to the proposed credentials being
- * constructed by execve().
- */
- static int get_file_caps(struct linux_binprm *bprm, const struct file *file,
- bool *effective, bool *has_fcap)
- {
- int rc = 0;
- struct cpu_vfs_cap_data vcaps;
- cap_clear(bprm->cred->cap_permitted);
- if (!file_caps_enabled)
- return 0;
- if (!mnt_may_suid(file->f_path.mnt))
- return 0;
- /*
- * This check is redundant with mnt_may_suid() but is kept to make
- * explicit that capability bits are limited to s_user_ns and its
- * descendants.
- */
- if (!current_in_userns(file->f_path.mnt->mnt_sb->s_user_ns))
- return 0;
- rc = get_vfs_caps_from_disk(file_mnt_idmap(file),
- file->f_path.dentry, &vcaps);
- if (rc < 0) {
- if (rc == -EINVAL)
- printk(KERN_NOTICE "Invalid argument reading file caps for %s\n",
- bprm->filename);
- else if (rc == -ENODATA)
- rc = 0;
- goto out;
- }
- rc = bprm_caps_from_vfs_caps(&vcaps, bprm, effective, has_fcap);
- out:
- if (rc)
- cap_clear(bprm->cred->cap_permitted);
- return rc;
- }
- static inline bool root_privileged(void) { return !issecure(SECURE_NOROOT); }
- static inline bool __is_real(kuid_t uid, struct cred *cred)
- { return uid_eq(cred->uid, uid); }
- static inline bool __is_eff(kuid_t uid, struct cred *cred)
- { return uid_eq(cred->euid, uid); }
- static inline bool __is_suid(kuid_t uid, struct cred *cred)
- { return !__is_real(uid, cred) && __is_eff(uid, cred); }
- /*
- * handle_privileged_root - Handle case of privileged root
- * @bprm: The execution parameters, including the proposed creds
- * @has_fcap: Are any file capabilities set?
- * @effective: Do we have effective root privilege?
- * @root_uid: This namespace' root UID WRT initial USER namespace
- *
- * Handle the case where root is privileged and hasn't been neutered by
- * SECURE_NOROOT. If file capabilities are set, they won't be combined with
- * set UID root and nothing is changed. If we are root, cap_permitted is
- * updated. If we have become set UID root, the effective bit is set.
- */
- static void handle_privileged_root(struct linux_binprm *bprm, bool has_fcap,
- bool *effective, kuid_t root_uid)
- {
- const struct cred *old = current_cred();
- struct cred *new = bprm->cred;
- if (!root_privileged())
- return;
- /*
- * If the legacy file capability is set, then don't set privs
- * for a setuid root binary run by a non-root user. Do set it
- * for a root user just to cause least surprise to an admin.
- */
- if (has_fcap && __is_suid(root_uid, new)) {
- warn_setuid_and_fcaps_mixed(bprm->filename);
- return;
- }
- /*
- * To support inheritance of root-permissions and suid-root
- * executables under compatibility mode, we override the
- * capability sets for the file.
- */
- if (__is_eff(root_uid, new) || __is_real(root_uid, new)) {
- /* pP' = (cap_bset & ~0) | (pI & ~0) */
- new->cap_permitted = cap_combine(old->cap_bset,
- old->cap_inheritable);
- }
- /*
- * If only the real uid is 0, we do not set the effective bit.
- */
- if (__is_eff(root_uid, new))
- *effective = true;
- }
- #define __cap_gained(field, target, source) \
- !cap_issubset(target->cap_##field, source->cap_##field)
- #define __cap_grew(target, source, cred) \
- !cap_issubset(cred->cap_##target, cred->cap_##source)
- #define __cap_full(field, cred) \
- cap_issubset(CAP_FULL_SET, cred->cap_##field)
- static inline bool __is_setuid(struct cred *new, const struct cred *old)
- { return !uid_eq(new->euid, old->uid); }
- static inline bool __is_setgid(struct cred *new, const struct cred *old)
- { return !gid_eq(new->egid, old->gid); }
- /*
- * 1) Audit candidate if current->cap_effective is set
- *
- * We do not bother to audit if 3 things are true:
- * 1) cap_effective has all caps
- * 2) we became root *OR* are were already root
- * 3) root is supposed to have all caps (SECURE_NOROOT)
- * Since this is just a normal root execing a process.
- *
- * Number 1 above might fail if you don't have a full bset, but I think
- * that is interesting information to audit.
- *
- * A number of other conditions require logging:
- * 2) something prevented setuid root getting all caps
- * 3) non-setuid root gets fcaps
- * 4) non-setuid root gets ambient
- */
- static inline bool nonroot_raised_pE(struct cred *new, const struct cred *old,
- kuid_t root, bool has_fcap)
- {
- bool ret = false;
- if ((__cap_grew(effective, ambient, new) &&
- !(__cap_full(effective, new) &&
- (__is_eff(root, new) || __is_real(root, new)) &&
- root_privileged())) ||
- (root_privileged() &&
- __is_suid(root, new) &&
- !__cap_full(effective, new)) ||
- (!__is_setuid(new, old) &&
- ((has_fcap &&
- __cap_gained(permitted, new, old)) ||
- __cap_gained(ambient, new, old))))
- ret = true;
- return ret;
- }
- /**
- * cap_bprm_creds_from_file - Set up the proposed credentials for execve().
- * @bprm: The execution parameters, including the proposed creds
- * @file: The file to pull the credentials from
- *
- * Set up the proposed credentials for a new execution context being
- * constructed by execve(). The proposed creds in @bprm->cred is altered,
- * which won't take effect immediately.
- *
- * Return: 0 if successful, -ve on error.
- */
- int cap_bprm_creds_from_file(struct linux_binprm *bprm, const struct file *file)
- {
- /* Process setpcap binaries and capabilities for uid 0 */
- const struct cred *old = current_cred();
- struct cred *new = bprm->cred;
- bool effective = false, has_fcap = false, is_setid;
- int ret;
- kuid_t root_uid;
- if (WARN_ON(!cap_ambient_invariant_ok(old)))
- return -EPERM;
- ret = get_file_caps(bprm, file, &effective, &has_fcap);
- if (ret < 0)
- return ret;
- root_uid = make_kuid(new->user_ns, 0);
- handle_privileged_root(bprm, has_fcap, &effective, root_uid);
- /* if we have fs caps, clear dangerous personality flags */
- if (__cap_gained(permitted, new, old))
- bprm->per_clear |= PER_CLEAR_ON_SETID;
- /* Don't let someone trace a set[ug]id/setpcap binary with the revised
- * credentials unless they have the appropriate permit.
- *
- * In addition, if NO_NEW_PRIVS, then ensure we get no new privs.
- */
- is_setid = __is_setuid(new, old) || __is_setgid(new, old);
- if ((is_setid || __cap_gained(permitted, new, old)) &&
- ((bprm->unsafe & ~LSM_UNSAFE_PTRACE) ||
- !ptracer_capable(current, new->user_ns))) {
- /* downgrade; they get no more than they had, and maybe less */
- if (!ns_capable(new->user_ns, CAP_SETUID) ||
- (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS)) {
- new->euid = new->uid;
- new->egid = new->gid;
- }
- new->cap_permitted = cap_intersect(new->cap_permitted,
- old->cap_permitted);
- }
- new->suid = new->fsuid = new->euid;
- new->sgid = new->fsgid = new->egid;
- /* File caps or setid cancels ambient. */
- if (has_fcap || is_setid)
- cap_clear(new->cap_ambient);
- /*
- * Now that we've computed pA', update pP' to give:
- * pP' = (X & fP) | (pI & fI) | pA'
- */
- new->cap_permitted = cap_combine(new->cap_permitted, new->cap_ambient);
- /*
- * Set pE' = (fE ? pP' : pA'). Because pA' is zero if fE is set,
- * this is the same as pE' = (fE ? pP' : 0) | pA'.
- */
- if (effective)
- new->cap_effective = new->cap_permitted;
- else
- new->cap_effective = new->cap_ambient;
- if (WARN_ON(!cap_ambient_invariant_ok(new)))
- return -EPERM;
- if (nonroot_raised_pE(new, old, root_uid, has_fcap)) {
- ret = audit_log_bprm_fcaps(bprm, new, old);
- if (ret < 0)
- return ret;
- }
- new->securebits &= ~issecure_mask(SECURE_KEEP_CAPS);
- if (WARN_ON(!cap_ambient_invariant_ok(new)))
- return -EPERM;
- /* Check for privilege-elevated exec. */
- if (is_setid ||
- (!__is_real(root_uid, new) &&
- (effective ||
- __cap_grew(permitted, ambient, new))))
- bprm->secureexec = 1;
- return 0;
- }
- /**
- * cap_inode_setxattr - Determine whether an xattr may be altered
- * @dentry: The inode/dentry being altered
- * @name: The name of the xattr to be changed
- * @value: The value that the xattr will be changed to
- * @size: The size of value
- * @flags: The replacement flag
- *
- * Determine whether an xattr may be altered or set on an inode, returning 0 if
- * permission is granted, -ve if denied.
- *
- * This is used to make sure security xattrs don't get updated or set by those
- * who aren't privileged to do so.
- */
- int cap_inode_setxattr(struct dentry *dentry, const char *name,
- const void *value, size_t size, int flags)
- {
- struct user_namespace *user_ns = dentry->d_sb->s_user_ns;
- /* Ignore non-security xattrs */
- if (strncmp(name, XATTR_SECURITY_PREFIX,
- XATTR_SECURITY_PREFIX_LEN) != 0)
- return 0;
- /*
- * For XATTR_NAME_CAPS the check will be done in
- * cap_convert_nscap(), called by setxattr()
- */
- if (strcmp(name, XATTR_NAME_CAPS) == 0)
- return 0;
- if (!ns_capable(user_ns, CAP_SYS_ADMIN))
- return -EPERM;
- return 0;
- }
- /**
- * cap_inode_removexattr - Determine whether an xattr may be removed
- *
- * @idmap: idmap of the mount the inode was found from
- * @dentry: The inode/dentry being altered
- * @name: The name of the xattr to be changed
- *
- * Determine whether an xattr may be removed from an inode, returning 0 if
- * permission is granted, -ve if denied.
- *
- * If the inode has been found through an idmapped mount the idmap of
- * the vfsmount must be passed through @idmap. This function will then
- * take care to map the inode according to @idmap before checking
- * permissions. On non-idmapped mounts or if permission checking is to be
- * performed on the raw inode simply pass @nop_mnt_idmap.
- *
- * This is used to make sure security xattrs don't get removed by those who
- * aren't privileged to remove them.
- */
- int cap_inode_removexattr(struct mnt_idmap *idmap,
- struct dentry *dentry, const char *name)
- {
- struct user_namespace *user_ns = dentry->d_sb->s_user_ns;
- /* Ignore non-security xattrs */
- if (strncmp(name, XATTR_SECURITY_PREFIX,
- XATTR_SECURITY_PREFIX_LEN) != 0)
- return 0;
- if (strcmp(name, XATTR_NAME_CAPS) == 0) {
- /* security.capability gets namespaced */
- struct inode *inode = d_backing_inode(dentry);
- if (!inode)
- return -EINVAL;
- if (!capable_wrt_inode_uidgid(idmap, inode, CAP_SETFCAP))
- return -EPERM;
- return 0;
- }
- if (!ns_capable(user_ns, CAP_SYS_ADMIN))
- return -EPERM;
- return 0;
- }
- /*
- * cap_emulate_setxuid() fixes the effective / permitted capabilities of
- * a process after a call to setuid, setreuid, or setresuid.
- *
- * 1) When set*uiding _from_ one of {r,e,s}uid == 0 _to_ all of
- * {r,e,s}uid != 0, the permitted and effective capabilities are
- * cleared.
- *
- * 2) When set*uiding _from_ euid == 0 _to_ euid != 0, the effective
- * capabilities of the process are cleared.
- *
- * 3) When set*uiding _from_ euid != 0 _to_ euid == 0, the effective
- * capabilities are set to the permitted capabilities.
- *
- * fsuid is handled elsewhere. fsuid == 0 and {r,e,s}uid!= 0 should
- * never happen.
- *
- * -astor
- *
- * cevans - New behaviour, Oct '99
- * A process may, via prctl(), elect to keep its capabilities when it
- * calls setuid() and switches away from uid==0. Both permitted and
- * effective sets will be retained.
- * Without this change, it was impossible for a daemon to drop only some
- * of its privilege. The call to setuid(!=0) would drop all privileges!
- * Keeping uid 0 is not an option because uid 0 owns too many vital
- * files..
- * Thanks to Olaf Kirch and Peter Benie for spotting this.
- */
- static inline void cap_emulate_setxuid(struct cred *new, const struct cred *old)
- {
- kuid_t root_uid = make_kuid(old->user_ns, 0);
- if ((uid_eq(old->uid, root_uid) ||
- uid_eq(old->euid, root_uid) ||
- uid_eq(old->suid, root_uid)) &&
- (!uid_eq(new->uid, root_uid) &&
- !uid_eq(new->euid, root_uid) &&
- !uid_eq(new->suid, root_uid))) {
- if (!issecure(SECURE_KEEP_CAPS)) {
- cap_clear(new->cap_permitted);
- cap_clear(new->cap_effective);
- }
- /*
- * Pre-ambient programs expect setresuid to nonroot followed
- * by exec to drop capabilities. We should make sure that
- * this remains the case.
- */
- cap_clear(new->cap_ambient);
- }
- if (uid_eq(old->euid, root_uid) && !uid_eq(new->euid, root_uid))
- cap_clear(new->cap_effective);
- if (!uid_eq(old->euid, root_uid) && uid_eq(new->euid, root_uid))
- new->cap_effective = new->cap_permitted;
- }
- /**
- * cap_task_fix_setuid - Fix up the results of setuid() call
- * @new: The proposed credentials
- * @old: The current task's current credentials
- * @flags: Indications of what has changed
- *
- * Fix up the results of setuid() call before the credential changes are
- * actually applied.
- *
- * Return: 0 to grant the changes, -ve to deny them.
- */
- int cap_task_fix_setuid(struct cred *new, const struct cred *old, int flags)
- {
- switch (flags) {
- case LSM_SETID_RE:
- case LSM_SETID_ID:
- case LSM_SETID_RES:
- /* juggle the capabilities to follow [RES]UID changes unless
- * otherwise suppressed */
- if (!issecure(SECURE_NO_SETUID_FIXUP))
- cap_emulate_setxuid(new, old);
- break;
- case LSM_SETID_FS:
- /* juggle the capabilities to follow FSUID changes, unless
- * otherwise suppressed
- *
- * FIXME - is fsuser used for all CAP_FS_MASK capabilities?
- * if not, we might be a bit too harsh here.
- */
- if (!issecure(SECURE_NO_SETUID_FIXUP)) {
- kuid_t root_uid = make_kuid(old->user_ns, 0);
- if (uid_eq(old->fsuid, root_uid) && !uid_eq(new->fsuid, root_uid))
- new->cap_effective =
- cap_drop_fs_set(new->cap_effective);
- if (!uid_eq(old->fsuid, root_uid) && uid_eq(new->fsuid, root_uid))
- new->cap_effective =
- cap_raise_fs_set(new->cap_effective,
- new->cap_permitted);
- }
- break;
- default:
- return -EINVAL;
- }
- return 0;
- }
- /*
- * Rationale: code calling task_setscheduler, task_setioprio, and
- * task_setnice, assumes that
- * . if capable(cap_sys_nice), then those actions should be allowed
- * . if not capable(cap_sys_nice), but acting on your own processes,
- * then those actions should be allowed
- * This is insufficient now since you can call code without suid, but
- * yet with increased caps.
- * So we check for increased caps on the target process.
- */
- static int cap_safe_nice(struct task_struct *p)
- {
- int is_subset, ret = 0;
- rcu_read_lock();
- is_subset = cap_issubset(__task_cred(p)->cap_permitted,
- current_cred()->cap_permitted);
- if (!is_subset && !ns_capable(__task_cred(p)->user_ns, CAP_SYS_NICE))
- ret = -EPERM;
- rcu_read_unlock();
- return ret;
- }
- /**
- * cap_task_setscheduler - Determine if scheduler policy change is permitted
- * @p: The task to affect
- *
- * Determine if the requested scheduler policy change is permitted for the
- * specified task.
- *
- * Return: 0 if permission is granted, -ve if denied.
- */
- int cap_task_setscheduler(struct task_struct *p)
- {
- return cap_safe_nice(p);
- }
- /**
- * cap_task_setioprio - Determine if I/O priority change is permitted
- * @p: The task to affect
- * @ioprio: The I/O priority to set
- *
- * Determine if the requested I/O priority change is permitted for the specified
- * task.
- *
- * Return: 0 if permission is granted, -ve if denied.
- */
- int cap_task_setioprio(struct task_struct *p, int ioprio)
- {
- return cap_safe_nice(p);
- }
- /**
- * cap_task_setnice - Determine if task priority change is permitted
- * @p: The task to affect
- * @nice: The nice value to set
- *
- * Determine if the requested task priority change is permitted for the
- * specified task.
- *
- * Return: 0 if permission is granted, -ve if denied.
- */
- int cap_task_setnice(struct task_struct *p, int nice)
- {
- return cap_safe_nice(p);
- }
- /*
- * Implement PR_CAPBSET_DROP. Attempt to remove the specified capability from
- * the current task's bounding set. Returns 0 on success, -ve on error.
- */
- static int cap_prctl_drop(unsigned long cap)
- {
- struct cred *new;
- if (!ns_capable(current_user_ns(), CAP_SETPCAP))
- return -EPERM;
- if (!cap_valid(cap))
- return -EINVAL;
- new = prepare_creds();
- if (!new)
- return -ENOMEM;
- cap_lower(new->cap_bset, cap);
- return commit_creds(new);
- }
- /**
- * cap_task_prctl - Implement process control functions for this security module
- * @option: The process control function requested
- * @arg2: The argument data for this function
- * @arg3: The argument data for this function
- * @arg4: The argument data for this function
- * @arg5: The argument data for this function
- *
- * Allow process control functions (sys_prctl()) to alter capabilities; may
- * also deny access to other functions not otherwise implemented here.
- *
- * Return: 0 or +ve on success, -ENOSYS if this function is not implemented
- * here, other -ve on error. If -ENOSYS is returned, sys_prctl() and other LSM
- * modules will consider performing the function.
- */
- int cap_task_prctl(int option, unsigned long arg2, unsigned long arg3,
- unsigned long arg4, unsigned long arg5)
- {
- const struct cred *old = current_cred();
- struct cred *new;
- switch (option) {
- case PR_CAPBSET_READ:
- if (!cap_valid(arg2))
- return -EINVAL;
- return !!cap_raised(old->cap_bset, arg2);
- case PR_CAPBSET_DROP:
- return cap_prctl_drop(arg2);
- /*
- * The next four prctl's remain to assist with transitioning a
- * system from legacy UID=0 based privilege (when filesystem
- * capabilities are not in use) to a system using filesystem
- * capabilities only - as the POSIX.1e draft intended.
- *
- * Note:
- *
- * PR_SET_SECUREBITS =
- * issecure_mask(SECURE_KEEP_CAPS_LOCKED)
- * | issecure_mask(SECURE_NOROOT)
- * | issecure_mask(SECURE_NOROOT_LOCKED)
- * | issecure_mask(SECURE_NO_SETUID_FIXUP)
- * | issecure_mask(SECURE_NO_SETUID_FIXUP_LOCKED)
- *
- * will ensure that the current process and all of its
- * children will be locked into a pure
- * capability-based-privilege environment.
- */
- case PR_SET_SECUREBITS:
- if ((((old->securebits & SECURE_ALL_LOCKS) >> 1)
- & (old->securebits ^ arg2)) /*[1]*/
- || ((old->securebits & SECURE_ALL_LOCKS & ~arg2)) /*[2]*/
- || (arg2 & ~(SECURE_ALL_LOCKS | SECURE_ALL_BITS)) /*[3]*/
- || (cap_capable(current_cred(),
- current_cred()->user_ns,
- CAP_SETPCAP,
- CAP_OPT_NONE) != 0) /*[4]*/
- /*
- * [1] no changing of bits that are locked
- * [2] no unlocking of locks
- * [3] no setting of unsupported bits
- * [4] doing anything requires privilege (go read about
- * the "sendmail capabilities bug")
- */
- )
- /* cannot change a locked bit */
- return -EPERM;
- new = prepare_creds();
- if (!new)
- return -ENOMEM;
- new->securebits = arg2;
- return commit_creds(new);
- case PR_GET_SECUREBITS:
- return old->securebits;
- case PR_GET_KEEPCAPS:
- return !!issecure(SECURE_KEEP_CAPS);
- case PR_SET_KEEPCAPS:
- if (arg2 > 1) /* Note, we rely on arg2 being unsigned here */
- return -EINVAL;
- if (issecure(SECURE_KEEP_CAPS_LOCKED))
- return -EPERM;
- new = prepare_creds();
- if (!new)
- return -ENOMEM;
- if (arg2)
- new->securebits |= issecure_mask(SECURE_KEEP_CAPS);
- else
- new->securebits &= ~issecure_mask(SECURE_KEEP_CAPS);
- return commit_creds(new);
- case PR_CAP_AMBIENT:
- if (arg2 == PR_CAP_AMBIENT_CLEAR_ALL) {
- if (arg3 | arg4 | arg5)
- return -EINVAL;
- new = prepare_creds();
- if (!new)
- return -ENOMEM;
- cap_clear(new->cap_ambient);
- return commit_creds(new);
- }
- if (((!cap_valid(arg3)) | arg4 | arg5))
- return -EINVAL;
- if (arg2 == PR_CAP_AMBIENT_IS_SET) {
- return !!cap_raised(current_cred()->cap_ambient, arg3);
- } else if (arg2 != PR_CAP_AMBIENT_RAISE &&
- arg2 != PR_CAP_AMBIENT_LOWER) {
- return -EINVAL;
- } else {
- if (arg2 == PR_CAP_AMBIENT_RAISE &&
- (!cap_raised(current_cred()->cap_permitted, arg3) ||
- !cap_raised(current_cred()->cap_inheritable,
- arg3) ||
- issecure(SECURE_NO_CAP_AMBIENT_RAISE)))
- return -EPERM;
- new = prepare_creds();
- if (!new)
- return -ENOMEM;
- if (arg2 == PR_CAP_AMBIENT_RAISE)
- cap_raise(new->cap_ambient, arg3);
- else
- cap_lower(new->cap_ambient, arg3);
- return commit_creds(new);
- }
- default:
- /* No functionality available - continue with default */
- return -ENOSYS;
- }
- }
- /**
- * cap_vm_enough_memory - Determine whether a new virtual mapping is permitted
- * @mm: The VM space in which the new mapping is to be made
- * @pages: The size of the mapping
- *
- * Determine whether the allocation of a new virtual mapping by the current
- * task is permitted.
- *
- * Return: 0 if permission granted, negative error code if not.
- */
- int cap_vm_enough_memory(struct mm_struct *mm, long pages)
- {
- return cap_capable(current_cred(), &init_user_ns, CAP_SYS_ADMIN,
- CAP_OPT_NOAUDIT);
- }
- /**
- * cap_mmap_addr - check if able to map given addr
- * @addr: address attempting to be mapped
- *
- * If the process is attempting to map memory below dac_mmap_min_addr they need
- * CAP_SYS_RAWIO. The other parameters to this function are unused by the
- * capability security module.
- *
- * Return: 0 if this mapping should be allowed or -EPERM if not.
- */
- int cap_mmap_addr(unsigned long addr)
- {
- int ret = 0;
- if (addr < dac_mmap_min_addr) {
- ret = cap_capable(current_cred(), &init_user_ns, CAP_SYS_RAWIO,
- CAP_OPT_NONE);
- /* set PF_SUPERPRIV if it turns out we allow the low mmap */
- if (ret == 0)
- current->flags |= PF_SUPERPRIV;
- }
- return ret;
- }
- int cap_mmap_file(struct file *file, unsigned long reqprot,
- unsigned long prot, unsigned long flags)
- {
- return 0;
- }
- #ifdef CONFIG_SECURITY
- static const struct lsm_id capability_lsmid = {
- .name = "capability",
- .id = LSM_ID_CAPABILITY,
- };
- static struct security_hook_list capability_hooks[] __ro_after_init = {
- LSM_HOOK_INIT(capable, cap_capable),
- LSM_HOOK_INIT(settime, cap_settime),
- LSM_HOOK_INIT(ptrace_access_check, cap_ptrace_access_check),
- LSM_HOOK_INIT(ptrace_traceme, cap_ptrace_traceme),
- LSM_HOOK_INIT(capget, cap_capget),
- LSM_HOOK_INIT(capset, cap_capset),
- LSM_HOOK_INIT(bprm_creds_from_file, cap_bprm_creds_from_file),
- LSM_HOOK_INIT(inode_need_killpriv, cap_inode_need_killpriv),
- LSM_HOOK_INIT(inode_killpriv, cap_inode_killpriv),
- LSM_HOOK_INIT(inode_getsecurity, cap_inode_getsecurity),
- LSM_HOOK_INIT(mmap_addr, cap_mmap_addr),
- LSM_HOOK_INIT(mmap_file, cap_mmap_file),
- LSM_HOOK_INIT(task_fix_setuid, cap_task_fix_setuid),
- LSM_HOOK_INIT(task_prctl, cap_task_prctl),
- LSM_HOOK_INIT(task_setscheduler, cap_task_setscheduler),
- LSM_HOOK_INIT(task_setioprio, cap_task_setioprio),
- LSM_HOOK_INIT(task_setnice, cap_task_setnice),
- LSM_HOOK_INIT(vm_enough_memory, cap_vm_enough_memory),
- };
- static int __init capability_init(void)
- {
- security_add_hooks(capability_hooks, ARRAY_SIZE(capability_hooks),
- &capability_lsmid);
- return 0;
- }
- DEFINE_LSM(capability) = {
- .name = "capability",
- .order = LSM_ORDER_FIRST,
- .init = capability_init,
- };
- #endif /* CONFIG_SECURITY */
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