diff options
| -rw-r--r-- | security/commoncap.c | 72 |
1 files changed, 30 insertions, 42 deletions
diff --git a/security/commoncap.c b/security/commoncap.c index b9d613e0ef14..9fe46e22c7f2 100644 --- a/security/commoncap.c +++ b/security/commoncap.c @@ -822,15 +822,20 @@ int cap_task_setnice(struct task_struct *p, int nice) * 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 long cap_prctl_drop(struct cred *new, unsigned long cap) +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 0; + return commit_creds(new); } /** @@ -848,26 +853,17 @@ static long cap_prctl_drop(struct cred *new, unsigned long cap) 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; - long error = 0; - - new = prepare_creds(); - if (!new) - return -ENOMEM; switch (option) { case PR_CAPBSET_READ: - error = -EINVAL; if (!cap_valid(arg2)) - goto error; - error = !!cap_raised(new->cap_bset, arg2); - goto no_change; + return -EINVAL; + return !!cap_raised(old->cap_bset, arg2); case PR_CAPBSET_DROP: - error = cap_prctl_drop(new, arg2); - if (error < 0) - goto error; - goto changed; + return cap_prctl_drop(arg2); /* * The next four prctl's remain to assist with transitioning a @@ -889,10 +885,9 @@ int cap_task_prctl(int option, unsigned long arg2, unsigned long arg3, * capability-based-privilege environment. */ case PR_SET_SECUREBITS: - error = -EPERM; - if ((((new->securebits & SECURE_ALL_LOCKS) >> 1) - & (new->securebits ^ arg2)) /*[1]*/ - || ((new->securebits & SECURE_ALL_LOCKS & ~arg2)) /*[2]*/ + 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, @@ -906,46 +901,39 @@ int cap_task_prctl(int option, unsigned long arg2, unsigned long arg3, */ ) /* cannot change a locked bit */ - goto error; + return -EPERM; + + new = prepare_creds(); + if (!new) + return -ENOMEM; new->securebits = arg2; - goto changed; + return commit_creds(new); case PR_GET_SECUREBITS: - error = new->securebits; - goto no_change; + return old->securebits; case PR_GET_KEEPCAPS: - if (issecure(SECURE_KEEP_CAPS)) - error = 1; - goto no_change; + return !!issecure(SECURE_KEEP_CAPS); case PR_SET_KEEPCAPS: - error = -EINVAL; if (arg2 > 1) /* Note, we rely on arg2 being unsigned here */ - goto error; - error = -EPERM; + return -EINVAL; if (issecure(SECURE_KEEP_CAPS_LOCKED)) - goto error; + 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); - goto changed; + return commit_creds(new); default: /* No functionality available - continue with default */ - error = -ENOSYS; - goto error; + return -ENOSYS; } - - /* Functionality provided */ -changed: - return commit_creds(new); - -no_change: -error: - abort_creds(new); - return error; } /** |