4 files changed, 131 insertions, 160 deletions

diff --git a/security/Kconfig b/security/Kconfig
index 62ed4717d334..559293922a47 100644
--- a/security/Kconfig
+++ b/security/Kconfig
@@ -74,8 +74,7 @@ config SECURITY_NETWORK_XFRM
           If you are unsure how to answer this question, answer N.
 
 config SECURITY_FILE_CAPABILITIES
-        bool "File POSIX Capabilities (EXPERIMENTAL)"
-        depends on EXPERIMENTAL
+        bool "File POSIX Capabilities"
         default n
         help
           This enables filesystem capabilities, allowing you to give
diff --git a/security/commoncap.c b/security/commoncap.c
index 0b6537a3672d..4afbece37a08 100644
--- a/security/commoncap.c
+++ b/security/commoncap.c
@@ -162,8 +162,7 @@ void cap_capset_set (struct task_struct *target, kernel_cap_t *effective,
 
 static inline void bprm_clear_caps(struct linux_binprm *bprm)
 {
-        cap_clear(bprm->cap_inheritable);
-        cap_clear(bprm->cap_permitted);
+        cap_clear(bprm->cap_post_exec_permitted);
         bprm->cap_effective = false;
 }
 
@@ -198,6 +197,7 @@ static inline int cap_from_disk(struct vfs_cap_data *caps,
 {
         __u32 magic_etc;
         unsigned tocopy, i;
+        int ret;
 
         if (size < sizeof(magic_etc))
                 return -EINVAL;
@@ -225,19 +225,40 @@ static inline int cap_from_disk(struct vfs_cap_data *caps,
                 bprm->cap_effective = false;
         }
 
-        for (i = 0; i < tocopy; ++i) {
-                bprm->cap_permitted.cap[i] =
-                        le32_to_cpu(caps->data[i].permitted);
-                bprm->cap_inheritable.cap[i] =
-                        le32_to_cpu(caps->data[i].inheritable);
-        }
-        while (i < VFS_CAP_U32) {
-                bprm->cap_permitted.cap[i] = 0;
-                bprm->cap_inheritable.cap[i] = 0;
-                i++;
+        ret = 0;
+
+        CAP_FOR_EACH_U32(i) {
+                __u32 value_cpu;
+
+                if (i >= tocopy) {
+                        /*
+                         * Legacy capability sets have no upper bits
+                         */
+                        bprm->cap_post_exec_permitted.cap[i] = 0;
+                        continue;
+                }
+                /*
+                 * pP' = (X & fP) | (pI & fI)
+                 */
+                value_cpu = le32_to_cpu(caps->data[i].permitted);
+                bprm->cap_post_exec_permitted.cap[i] =
+                        (current->cap_bset.cap[i] & value_cpu) |
+                        (current->cap_inheritable.cap[i] &
+                                le32_to_cpu(caps->data[i].inheritable));
+                if (value_cpu & ~bprm->cap_post_exec_permitted.cap[i]) {
+                        /*
+                         * insufficient to execute correctly
+                         */
+                        ret = -EPERM;
+                }
         }
 
-        return 0;
+        /*
+         * 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 bprm->cap_effective ? ret : 0;
 }
 
 /* Locate any VFS capabilities: */
@@ -269,9 +290,9 @@ static int get_file_caps(struct linux_binprm *bprm)
                 goto out;
 
         rc = cap_from_disk(&vcaps, bprm, rc);
-        if (rc)
+        if (rc == -EINVAL)
                 printk(KERN_NOTICE "%s: cap_from_disk returned %d for %s\n",
-                        __func__, rc, bprm->filename);
+                       __func__, rc, bprm->filename);
 
 out:
         dput(dentry);
@@ -304,25 +325,24 @@ int cap_bprm_set_security (struct linux_binprm *bprm)
         int ret;
 
         ret = get_file_caps(bprm);
-        if (ret)
-                printk(KERN_NOTICE "%s: get_file_caps returned %d for %s\n",
-                        __func__, ret, bprm->filename);
-
-        /*  To support inheritance of root-permissions and suid-root
-         *  executables under compatibility mode, we raise all three
-         *  capability sets for the file.
-         *
-         *  If only the real uid is 0, we only raise the inheritable
-         *  and permitted sets of the executable file.
-         */
 
-        if (!issecure (SECURE_NOROOT)) {
+        if (!issecure(SECURE_NOROOT)) {
+                /*
+                 * To support inheritance of root-permissions and suid-root
+                 * executables under compatibility mode, we override the
+                 * capability sets for the file.
+                 *
+                 * If only the real uid is 0, we do not set the effective
+                 * bit.
+                 */
                 if (bprm->e_uid == 0 || current->uid == 0) {
-                        cap_set_full (bprm->cap_inheritable);
-                        cap_set_full (bprm->cap_permitted);
+                        /* pP' = (cap_bset & ~0) | (pI & ~0) */
+                        bprm->cap_post_exec_permitted = cap_combine(
+                                current->cap_bset, current->cap_inheritable
+                                );
+                        bprm->cap_effective = (bprm->e_uid == 0);
+                        ret = 0;
                 }
-                if (bprm->e_uid == 0)
-                        bprm->cap_effective = true;
         }
 
         return ret;
@@ -330,17 +350,9 @@ int cap_bprm_set_security (struct linux_binprm *bprm)
 
 void cap_bprm_apply_creds (struct linux_binprm *bprm, int unsafe)
 {
-        /* Derived from fs/exec.c:compute_creds. */
-        kernel_cap_t new_permitted, working;
-
-        new_permitted = cap_intersect(bprm->cap_permitted,
-                                 current->cap_bset);
-        working = cap_intersect(bprm->cap_inheritable,
-                                 current->cap_inheritable);
-        new_permitted = cap_combine(new_permitted, working);
-
         if (bprm->e_uid != current->uid || bprm->e_gid != current->gid ||
-            !cap_issubset (new_permitted, current->cap_permitted)) {
+            !cap_issubset(bprm->cap_post_exec_permitted,
+                          current->cap_permitted)) {
                 set_dumpable(current->mm, suid_dumpable);
                 current->pdeath_signal = 0;
 
@@ -350,9 +362,9 @@ void cap_bprm_apply_creds (struct linux_binprm *bprm, int unsafe)
                                 bprm->e_gid = current->gid;
                         }
                         if (cap_limit_ptraced_target()) {
-                                new_permitted =
-                                        cap_intersect(new_permitted,
-                                                      current->cap_permitted);
+                                bprm->cap_post_exec_permitted = cap_intersect(
+                                        bprm->cap_post_exec_permitted,
+                                        current->cap_permitted);
                         }
                 }
         }
@@ -364,9 +376,9 @@ void cap_bprm_apply_creds (struct linux_binprm *bprm, int unsafe)
          * in the init_task struct. Thus we skip the usual
          * capability rules */
         if (!is_global_init(current)) {
-                current->cap_permitted = new_permitted;
+                current->cap_permitted = bprm->cap_post_exec_permitted;
                 if (bprm->cap_effective)
-                        current->cap_effective = new_permitted;
+                        current->cap_effective = bprm->cap_post_exec_permitted;
                 else
                         cap_clear(current->cap_effective);
         }
@@ -381,9 +393,7 @@ int cap_bprm_secureexec (struct linux_binprm *bprm)
         if (current->uid != 0) {
                 if (bprm->cap_effective)
                         return 1;
-                if (!cap_isclear(bprm->cap_permitted))
-                        return 1;
-                if (!cap_isclear(bprm->cap_inheritable))
+                if (!cap_isclear(bprm->cap_post_exec_permitted))
                         return 1;
         }
 
diff --git a/security/device_cgroup.c b/security/device_cgroup.c
index ddd92cec78ed..7bd296cca041 100644
--- a/security/device_cgroup.c
+++ b/security/device_cgroup.c
@@ -41,6 +41,7 @@ struct dev_whitelist_item {
         short type;
         short access;
         struct list_head list;
+        struct rcu_head rcu;
 };
 
 struct dev_cgroup {
@@ -59,6 +60,11 @@ static inline struct dev_cgroup *cgroup_to_devcgroup(struct cgroup *cgroup)
         return css_to_devcgroup(cgroup_subsys_state(cgroup, devices_subsys_id));
 }
 
+static inline struct dev_cgroup *task_devcgroup(struct task_struct *task)
+{
+        return css_to_devcgroup(task_subsys_state(task, devices_subsys_id));
+}
+
 struct cgroup_subsys devices_subsys;
 
 static int devcgroup_can_attach(struct cgroup_subsys *ss,
@@ -128,11 +134,19 @@ static int dev_whitelist_add(struct dev_cgroup *dev_cgroup,
         }
 
         if (whcopy != NULL)
-                list_add_tail(&whcopy->list, &dev_cgroup->whitelist);
+                list_add_tail_rcu(&whcopy->list, &dev_cgroup->whitelist);
         spin_unlock(&dev_cgroup->lock);
         return 0;
 }
 
+static void whitelist_item_free(struct rcu_head *rcu)
+{
+        struct dev_whitelist_item *item;
+
+        item = container_of(rcu, struct dev_whitelist_item, rcu);
+        kfree(item);
+}
+
 /*
  * called under cgroup_lock()
  * since the list is visible to other tasks, we need the spinlock also
@@ -156,8 +170,8 @@ static void dev_whitelist_rm(struct dev_cgroup *dev_cgroup,
 remove:
                 walk->access &= ~wh->access;
                 if (!walk->access) {
-                        list_del(&walk->list);
-                        kfree(walk);
+                        list_del_rcu(&walk->list);
+                        call_rcu(&walk->rcu, whitelist_item_free);
                 }
         }
         spin_unlock(&dev_cgroup->lock);
@@ -188,7 +202,7 @@ static struct cgroup_subsys_state *devcgroup_create(struct cgroup_subsys *ss,
                 }
                 wh->minor = wh->major = ~0;
                 wh->type = DEV_ALL;
-                wh->access = ACC_MKNOD | ACC_READ | ACC_WRITE;
+                wh->access = ACC_MASK;
                 list_add(&wh->list, &dev_cgroup->whitelist);
         } else {
                 parent_dev_cgroup = cgroup_to_devcgroup(parent_cgroup);
@@ -250,11 +264,10 @@ static char type_to_char(short type)
 
 static void set_majmin(char *str, unsigned m)
 {
-        memset(str, 0, MAJMINLEN);
         if (m == ~0)
-                sprintf(str, "*");
+                strcpy(str, "*");
         else
-                snprintf(str, MAJMINLEN, "%u", m);
+                sprintf(str, "%u", m);
 }
 
 static int devcgroup_seq_read(struct cgroup *cgroup, struct cftype *cft,
@@ -264,15 +277,15 @@ static int devcgroup_seq_read(struct cgroup *cgroup, struct cftype *cft,
         struct dev_whitelist_item *wh;
         char maj[MAJMINLEN], min[MAJMINLEN], acc[ACCLEN];
 
-        spin_lock(&devcgroup->lock);
-        list_for_each_entry(wh, &devcgroup->whitelist, list) {
+        rcu_read_lock();
+        list_for_each_entry_rcu(wh, &devcgroup->whitelist, list) {
                 set_access(acc, wh->access);
                 set_majmin(maj, wh->major);
                 set_majmin(min, wh->minor);
                 seq_printf(m, "%c %s:%s %s\n", type_to_char(wh->type),
                            maj, min, acc);
         }
-        spin_unlock(&devcgroup->lock);
+        rcu_read_unlock();
 
         return 0;
 }
@@ -312,10 +325,10 @@ static int may_access_whitelist(struct dev_cgroup *c,
  * when adding a new allow rule to a device whitelist, the rule
  * must be allowed in the parent device
  */
-static int parent_has_perm(struct cgroup *childcg,
+static int parent_has_perm(struct dev_cgroup *childcg,
                                   struct dev_whitelist_item *wh)
 {
-        struct cgroup *pcg = childcg->parent;
+        struct cgroup *pcg = childcg->css.cgroup->parent;
         struct dev_cgroup *parent;
         int ret;
 
@@ -341,39 +354,19 @@ static int parent_has_perm(struct cgroup *childcg,
  * new access is only allowed if you're in the top-level cgroup, or your
  * parent cgroup has the access you're asking for.
  */
-static ssize_t devcgroup_access_write(struct cgroup *cgroup, struct cftype *cft,
-                                struct file *file, const char __user *userbuf,
-                                size_t nbytes, loff_t *ppos)
+static int devcgroup_update_access(struct dev_cgroup *devcgroup,
+                                   int filetype, const char *buffer)
 {
-        struct cgroup *cur_cgroup;
-        struct dev_cgroup *devcgroup, *cur_devcgroup;
-        int filetype = cft->private;
-        char *buffer, *b;
+        struct dev_cgroup *cur_devcgroup;
+        const char *b;
+        char *endp;
         int retval = 0, count;
         struct dev_whitelist_item wh;
 
         if (!capable(CAP_SYS_ADMIN))
                 return -EPERM;
 
-        devcgroup = cgroup_to_devcgroup(cgroup);
-        cur_cgroup = task_cgroup(current, devices_subsys.subsys_id);
-        cur_devcgroup = cgroup_to_devcgroup(cur_cgroup);
-
-        buffer = kmalloc(nbytes+1, GFP_KERNEL);
-        if (!buffer)
-                return -ENOMEM;
-
-        if (copy_from_user(buffer, userbuf, nbytes)) {
-                retval = -EFAULT;
-                goto out1;
-        }
-        buffer[nbytes] = 0;     /* nul-terminate */
-
-        cgroup_lock();
-        if (cgroup_is_removed(cgroup)) {
-                retval = -ENODEV;
-                goto out2;
-        }
+        cur_devcgroup = task_devcgroup(current);
 
         memset(&wh, 0, sizeof(wh));
         b = buffer;
@@ -392,32 +385,23 @@ static ssize_t devcgroup_access_write(struct cgroup *cgroup, struct cftype *cft,
                 wh.type = DEV_CHAR;
                 break;
         default:
-                retval = -EINVAL;
-                goto out2;
+                return -EINVAL;
         }
         b++;
-        if (!isspace(*b)) {
-                retval = -EINVAL;
-                goto out2;
-        }
+        if (!isspace(*b))
+                return -EINVAL;
         b++;
         if (*b == '*') {
                 wh.major = ~0;
                 b++;
         } else if (isdigit(*b)) {
-                wh.major = 0;
-                while (isdigit(*b)) {
-                        wh.major = wh.major*10+(*b-'0');
-                        b++;
-                }
+                wh.major = simple_strtoul(b, &endp, 10);
+                b = endp;
         } else {
-                retval = -EINVAL;
-                goto out2;
-        }
-        if (*b != ':') {
-                retval = -EINVAL;
-                goto out2;
+                return -EINVAL;
         }
+        if (*b != ':')
+                return -EINVAL;
         b++;
 
         /* read minor */
@@ -425,19 +409,13 @@ static ssize_t devcgroup_access_write(struct cgroup *cgroup, struct cftype *cft,
                 wh.minor = ~0;
                 b++;
         } else if (isdigit(*b)) {
-                wh.minor = 0;
-                while (isdigit(*b)) {
-                        wh.minor = wh.minor*10+(*b-'0');
-                        b++;
-                }
+                wh.minor = simple_strtoul(b, &endp, 10);
+                b = endp;
         } else {
-                retval = -EINVAL;
-                goto out2;
-        }
-        if (!isspace(*b)) {
-                retval = -EINVAL;
-                goto out2;
+                return -EINVAL;
         }
+        if (!isspace(*b))
+                return -EINVAL;
         for (b++, count = 0; count < 3; count++, b++) {
                 switch (*b) {
                 case 'r':
@@ -454,8 +432,7 @@ static ssize_t devcgroup_access_write(struct cgroup *cgroup, struct cftype *cft,
                         count = 3;
                         break;
                 default:
-                        retval = -EINVAL;
-                        goto out2;
+                        return -EINVAL;
                 }
         }
 
@@ -463,38 +440,39 @@ handle:
         retval = 0;
         switch (filetype) {
         case DEVCG_ALLOW:
-                if (!parent_has_perm(cgroup, &wh))
-                        retval = -EPERM;
-                else
-                        retval = dev_whitelist_add(devcgroup, &wh);
-                break;
+                if (!parent_has_perm(devcgroup, &wh))
+                        return -EPERM;
+                return dev_whitelist_add(devcgroup, &wh);
         case DEVCG_DENY:
                 dev_whitelist_rm(devcgroup, &wh);
                 break;
         default:
-                retval = -EINVAL;
-                goto out2;
+                return -EINVAL;
         }
+        return 0;
+}
 
-        if (retval == 0)
-                retval = nbytes;
-
-out2:
+static int devcgroup_access_write(struct cgroup *cgrp, struct cftype *cft,
+                                  const char *buffer)
+{
+        int retval;
+        if (!cgroup_lock_live_group(cgrp))
+                return -ENODEV;
+        retval = devcgroup_update_access(cgroup_to_devcgroup(cgrp),
+                                         cft->private, buffer);
         cgroup_unlock();
-out1:
-        kfree(buffer);
         return retval;
 }
 
 static struct cftype dev_cgroup_files[] = {
         {
                 .name = "allow",
-                .write  = devcgroup_access_write,
+                .write_string  = devcgroup_access_write,
                 .private = DEVCG_ALLOW,
         },
         {
                 .name = "deny",
-                .write = devcgroup_access_write,
+                .write_string = devcgroup_access_write,
                 .private = DEVCG_DENY,
         },
         {
@@ -535,8 +513,8 @@ int devcgroup_inode_permission(struct inode *inode, int mask)
         if (!dev_cgroup)
                 return 0;
 
-        spin_lock(&dev_cgroup->lock);
-        list_for_each_entry(wh, &dev_cgroup->whitelist, list) {
+        rcu_read_lock();
+        list_for_each_entry_rcu(wh, &dev_cgroup->whitelist, list) {
                 if (wh->type & DEV_ALL)
                         goto acc_check;
                 if ((wh->type & DEV_BLOCK) && !S_ISBLK(inode->i_mode))
@@ -552,10 +530,10 @@ acc_check:
                         continue;
                 if ((mask & MAY_READ) && !(wh->access & ACC_READ))
                         continue;
-                spin_unlock(&dev_cgroup->lock);
+                rcu_read_unlock();
                 return 0;
         }
-        spin_unlock(&dev_cgroup->lock);
+        rcu_read_unlock();
 
         return -EPERM;
 }
@@ -570,7 +548,7 @@ int devcgroup_inode_mknod(int mode, dev_t dev)
         if (!dev_cgroup)
                 return 0;
 
-        spin_lock(&dev_cgroup->lock);
+        rcu_read_lock();
         list_for_each_entry(wh, &dev_cgroup->whitelist, list) {
                 if (wh->type & DEV_ALL)
                         goto acc_check;
@@ -585,9 +563,9 @@ int devcgroup_inode_mknod(int mode, dev_t dev)
 acc_check:
                 if (!(wh->access & ACC_MKNOD))
                         continue;
-                spin_unlock(&dev_cgroup->lock);
+                rcu_read_unlock();
                 return 0;
         }
-        spin_unlock(&dev_cgroup->lock);
+        rcu_read_unlock();
         return -EPERM;
 }
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index df0515dd4d12..da36dac6535f 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -25,7 +25,7 @@
 
 #include <linux/init.h>
 #include <linux/kernel.h>
-#include <linux/ptrace.h>
+#include <linux/tracehook.h>
 #include <linux/errno.h>
 #include <linux/sched.h>
 #include <linux/security.h>
@@ -1971,22 +1971,6 @@ static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
         return __vm_enough_memory(mm, pages, cap_sys_admin);
 }
 
-/**
- * task_tracer_task - return the task that is tracing the given task
- * @task:               task to consider
- *
- * Returns NULL if noone is tracing @task, or the &struct task_struct
- * pointer to its tracer.
- *
- * Must be called under rcu_read_lock().
- */
-static struct task_struct *task_tracer_task(struct task_struct *task)
-{
-        if (task->ptrace & PT_PTRACED)
-                return rcu_dereference(task->parent);
-        return NULL;
-}
-
 /* binprm security operations */
 
 static int selinux_bprm_alloc_security(struct linux_binprm *bprm)
@@ -2238,7 +2222,7 @@ static void selinux_bprm_apply_creds(struct linux_binprm *bprm, int unsafe)
                         u32 ptsid = 0;
 
                         rcu_read_lock();
-                        tracer = task_tracer_task(current);
+                        tracer = tracehook_tracer_task(current);
                         if (likely(tracer != NULL)) {
                                 sec = tracer->security;
                                 ptsid = sec->sid;
@@ -5247,7 +5231,7 @@ static int selinux_setprocattr(struct task_struct *p,
                    Otherwise, leave SID unchanged and fail. */
                 task_lock(p);
                 rcu_read_lock();
-                tracer = task_tracer_task(p);
+                tracer = tracehook_tracer_task(p);
                 if (tracer != NULL) {
                         struct task_security_struct *ptsec = tracer->security;
                         u32 ptsid = ptsec->sid;