#include <linux/prctl.h>
#include <linux/securebits.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(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;
+ }
+}
+
int cap_netlink_send(struct sock *sk, struct sk_buff *skb)
{
NETLINK_CB(skb).eff_cap = current_cap();
/**
* cap_capable - Determine whether a task has a particular effective capability
* @tsk: The task to query
+ * @cred: The credentials to use
* @cap: The capability to check for
* @audit: Whether to write an audit message or not
*
* 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_capable() cannot be used like the kernel's capable()
- * function. That is, it has the reverse semantics: cap_capable() returns 0
- * when a task has a capability, but the kernel's capable() returns 1 for this
- * case.
+ * 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(struct task_struct *tsk, int cap, int audit)
+int cap_capable(struct task_struct *tsk, const struct cred *cred, int cap,
+ int audit)
{
- __u32 cap_raised;
-
- /* Derived from include/linux/sched.h:capable. */
- rcu_read_lock();
- cap_raised = cap_raised(__task_cred(tsk)->cap_effective, cap);
- rcu_read_unlock();
- return cap_raised ? 0 : -EPERM;
+ return cap_raised(cred->cap_effective, cap) ? 0 : -EPERM;
}
/**
}
/**
- * cap_ptrace_may_access - Determine whether the current process may access
+ * cap_ptrace_access_check - Determine whether the current process may access
* another
* @child: The process to be accessed
* @mode: The mode of attachment.
* Determine whether a process may access another, returning 0 if permission
* granted, -ve if denied.
*/
-int cap_ptrace_may_access(struct task_struct *child, unsigned int mode)
+int cap_ptrace_access_check(struct task_struct *child, unsigned int mode)
{
int ret = 0;
/* they are so limited unless the current task has the CAP_SETPCAP
* capability
*/
- if (cap_capable(current, CAP_SETPCAP, SECURITY_CAP_AUDIT) == 0)
+ if (cap_capable(current, current_cred(), CAP_SETPCAP,
+ SECURITY_CAP_AUDIT) == 0)
return 0;
#endif
return 1;
struct inode *inode = dentry->d_inode;
int error;
- if (!inode->i_op || !inode->i_op->getxattr)
+ if (!inode->i_op->getxattr)
return 0;
error = inode->i_op->getxattr(dentry, XATTR_NAME_CAPS, NULL, 0);
{
struct inode *inode = dentry->d_inode;
- if (!inode->i_op || !inode->i_op->removexattr)
+ if (!inode->i_op->removexattr)
return 0;
return inode->i_op->removexattr(dentry, XATTR_NAME_CAPS);
memset(cpu_caps, 0, sizeof(struct cpu_vfs_cap_data));
- if (!inode || !inode->i_op || !inode->i_op->getxattr)
+ if (!inode || !inode->i_op->getxattr)
return -ENODATA;
size = inode->i_op->getxattr((struct dentry *)dentry, XATTR_NAME_CAPS, &caps,
if (!issecure(SECURE_NOROOT)) {
/*
+ * 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 (effective && new->uid != 0 && new->euid == 0) {
+ warn_setuid_and_fcaps_mixed(bprm->filename);
+ goto skip;
+ }
+ /*
* To support inheritance of root-permissions and suid-root
* executables under compatibility mode, we override the
* capability sets for the file.
if (new->euid == 0)
effective = true;
}
+skip:
/* Don't let someone trace a set[ug]id/setpcap binary with the revised
* credentials unless they have the appropriate permit
& (new->securebits ^ arg2)) /*[1]*/
|| ((new->securebits & SECURE_ALL_LOCKS & ~arg2)) /*[2]*/
|| (arg2 & ~(SECURE_ALL_LOCKS | SECURE_ALL_BITS)) /*[3]*/
- || (cap_capable(current, CAP_SETPCAP, SECURITY_CAP_AUDIT) != 0) /*[4]*/
+ || (cap_capable(current, current_cred(), CAP_SETPCAP,
+ SECURITY_CAP_AUDIT) != 0) /*[4]*/
/*
* [1] no changing of bits that are locked
* [2] no unlocking of locks
return commit_creds(new);
no_change:
- error = 0;
error:
abort_creds(new);
return error;
{
int cap_sys_admin = 0;
- if (cap_capable(current, CAP_SYS_ADMIN, SECURITY_CAP_NOAUDIT) == 0)
+ if (cap_capable(current, current_cred(), CAP_SYS_ADMIN,
+ SECURITY_CAP_NOAUDIT) == 0)
cap_sys_admin = 1;
return __vm_enough_memory(mm, pages, cap_sys_admin);
}
+
+/*
+ * cap_file_mmap - check if able to map given addr
+ * @file: unused
+ * @reqprot: unused
+ * @prot: unused
+ * @flags: unused
+ * @addr: address attempting to be mapped
+ * @addr_only: unused
+ *
+ * If the process is attempting to map memory below mmap_min_addr they need
+ * CAP_SYS_RAWIO. The other parameters to this function are unused by the
+ * capability security module. Returns 0 if this mapping should be allowed
+ * -EPERM if not.
+ */
+int cap_file_mmap(struct file *file, unsigned long reqprot,
+ unsigned long prot, unsigned long flags,
+ unsigned long addr, unsigned long addr_only)
+{
+ int ret = 0;
+
+ if (addr < dac_mmap_min_addr) {
+ ret = cap_capable(current, current_cred(), CAP_SYS_RAWIO,
+ SECURITY_CAP_AUDIT);
+ /* set PF_SUPERPRIV if it turns out we allow the low mmap */
+ if (ret == 0)
+ current->flags |= PF_SUPERPRIV;
+ }
+ return ret;
+}
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff