1 files changed, 151 insertions, 42 deletions

diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 28832e689800..2e8b4dfcbc74 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -18,7 +18,6 @@
  *      as published by the Free Software Foundation.
  */
 
-#include <linux/config.h>
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/kernel.h>
@@ -69,6 +68,7 @@
 #include <linux/sysctl.h>
 #include <linux/audit.h>
 #include <linux/string.h>
+#include <linux/selinux.h>
 
 #include "avc.h"
 #include "objsec.h"
@@ -246,6 +246,7 @@ static int superblock_alloc_security(struct super_block *sb)
         sbsec->sb = sb;
         sbsec->sid = SECINITSID_UNLABELED;
         sbsec->def_sid = SECINITSID_FILE;
+        sbsec->mntpoint_sid = SECINITSID_UNLABELED;
         sb->s_security = sbsec;
 
         return 0;
@@ -319,19 +320,53 @@ enum {
         Opt_context = 1,
         Opt_fscontext = 2,
         Opt_defcontext = 4,
+        Opt_rootcontext = 8,
 };
 
 static match_table_t tokens = {
         {Opt_context, "context=%s"},
         {Opt_fscontext, "fscontext=%s"},
         {Opt_defcontext, "defcontext=%s"},
+        {Opt_rootcontext, "rootcontext=%s"},
 };
 
 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
 
+static int may_context_mount_sb_relabel(u32 sid,
+                        struct superblock_security_struct *sbsec,
+                        struct task_security_struct *tsec)
+{
+        int rc;
+
+        rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
+                          FILESYSTEM__RELABELFROM, NULL);
+        if (rc)
+                return rc;
+
+        rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
+                          FILESYSTEM__RELABELTO, NULL);
+        return rc;
+}
+
+static int may_context_mount_inode_relabel(u32 sid,
+                        struct superblock_security_struct *sbsec,
+                        struct task_security_struct *tsec)
+{
+        int rc;
+        rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
+                          FILESYSTEM__RELABELFROM, NULL);
+        if (rc)
+                return rc;
+
+        rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
+                          FILESYSTEM__ASSOCIATE, NULL);
+        return rc;
+}
+
 static int try_context_mount(struct super_block *sb, void *data)
 {
         char *context = NULL, *defcontext = NULL;
+        char *fscontext = NULL, *rootcontext = NULL;
         const char *name;
         u32 sid;
         int alloc = 0, rc = 0, seen = 0;
@@ -374,7 +409,7 @@ static int try_context_mount(struct super_block *sb, void *data)
 
                         switch (token) {
                         case Opt_context:
-                                if (seen) {
+                                if (seen & (Opt_context|Opt_defcontext)) {
                                         rc = -EINVAL;
                                         printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
                                         goto out_free;
@@ -390,13 +425,13 @@ static int try_context_mount(struct super_block *sb, void *data)
                                 break;
 
                         case Opt_fscontext:
-                                if (seen & (Opt_context|Opt_fscontext)) {
+                                if (seen & Opt_fscontext) {
                                         rc = -EINVAL;
                                         printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
                                         goto out_free;
                                 }
-                                context = match_strdup(&args[0]);
-                                if (!context) {
+                                fscontext = match_strdup(&args[0]);
+                                if (!fscontext) {
                                         rc = -ENOMEM;
                                         goto out_free;
                                 }
@@ -405,6 +440,22 @@ static int try_context_mount(struct super_block *sb, void *data)
                                 seen |= Opt_fscontext;
                                 break;
 
+                        case Opt_rootcontext:
+                                if (seen & Opt_rootcontext) {
+                                        rc = -EINVAL;
+                                        printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
+                                        goto out_free;
+                                }
+                                rootcontext = match_strdup(&args[0]);
+                                if (!rootcontext) {
+                                        rc = -ENOMEM;
+                                        goto out_free;
+                                }
+                                if (!alloc)
+                                        alloc = 1;
+                                seen |= Opt_rootcontext;
+                                break;
+
                         case Opt_defcontext:
                                 if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
                                         rc = -EINVAL;
@@ -441,6 +492,28 @@ static int try_context_mount(struct super_block *sb, void *data)
         if (!seen)
                 goto out;
 
+        /* sets the context of the superblock for the fs being mounted. */
+        if (fscontext) {
+                rc = security_context_to_sid(fscontext, strlen(fscontext), &sid);
+                if (rc) {
+                        printk(KERN_WARNING "SELinux: security_context_to_sid"
+                               "(%s) failed for (dev %s, type %s) errno=%d\n",
+                               fscontext, sb->s_id, name, rc);
+                        goto out_free;
+                }
+
+                rc = may_context_mount_sb_relabel(sid, sbsec, tsec);
+                if (rc)
+                        goto out_free;
+
+                sbsec->sid = sid;
+        }
+
+        /*
+         * Switch to using mount point labeling behavior.
+         * sets the label used on all file below the mountpoint, and will set
+         * the superblock context if not already set.
+         */
         if (context) {
                 rc = security_context_to_sid(context, strlen(context), &sid);
                 if (rc) {
@@ -450,20 +523,34 @@ static int try_context_mount(struct super_block *sb, void *data)
                         goto out_free;
                 }
 
-                rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
-                                  FILESYSTEM__RELABELFROM, NULL);
+                rc = may_context_mount_sb_relabel(sid, sbsec, tsec);
                 if (rc)
                         goto out_free;
 
-                rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
-                                  FILESYSTEM__RELABELTO, NULL);
-                if (rc)
+                if (!fscontext)
+                        sbsec->sid = sid;
+                sbsec->mntpoint_sid = sid;
+
+                sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
+        }
+
+        if (rootcontext) {
+                struct inode *inode = sb->s_root->d_inode;
+                struct inode_security_struct *isec = inode->i_security;
+                rc = security_context_to_sid(rootcontext, strlen(rootcontext), &sid);
+                if (rc) {
+                        printk(KERN_WARNING "SELinux: security_context_to_sid"
+                               "(%s) failed for (dev %s, type %s) errno=%d\n",
+                               rootcontext, sb->s_id, name, rc);
                         goto out_free;
+                }
 
-                sbsec->sid = sid;
+                rc = may_context_mount_inode_relabel(sid, sbsec, tsec);
+                if (rc)
+                        goto out_free;
 
-                if (seen & Opt_context)
-                        sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
+                isec->sid = sid;
+                isec->initialized = 1;
         }
 
         if (defcontext) {
@@ -478,13 +565,7 @@ static int try_context_mount(struct super_block *sb, void *data)
                 if (sid == sbsec->def_sid)
                         goto out_free;
 
-                rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
-                                  FILESYSTEM__RELABELFROM, NULL);
-                if (rc)
-                        goto out_free;
-
-                rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
-                                  FILESYSTEM__ASSOCIATE, NULL);
+                rc = may_context_mount_inode_relabel(sid, sbsec, tsec);
                 if (rc)
                         goto out_free;
 
@@ -495,6 +576,8 @@ out_free:
         if (alloc) {
                 kfree(context);
                 kfree(defcontext);
+                kfree(fscontext);
+                kfree(rootcontext);
         }
 out:
         return rc;
@@ -876,8 +959,11 @@ static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dent
                         goto out;
                 isec->sid = sid;
                 break;
+        case SECURITY_FS_USE_MNTPOINT:
+                isec->sid = sbsec->mntpoint_sid;
+                break;
         default:
-                /* Default to the fs SID. */
+                /* Default to the fs superblock SID. */
                 isec->sid = sbsec->sid;
 
                 if (sbsec->proc) {
@@ -1843,7 +1929,8 @@ static inline int selinux_option(char *option, int len)
 {
         return (match_prefix("context=", sizeof("context=")-1, option, len) ||
                 match_prefix("fscontext=", sizeof("fscontext=")-1, option, len) ||
-                match_prefix("defcontext=", sizeof("defcontext=")-1, option, len));
+                match_prefix("defcontext=", sizeof("defcontext=")-1, option, len) ||
+                match_prefix("rootcontext=", sizeof("rootcontext=")-1, option, len));
 }
 
 static inline void take_option(char **to, char *from, int *first, int len)
@@ -2643,6 +2730,11 @@ static int selinux_task_getsid(struct task_struct *p)
         return task_has_perm(current, p, PROCESS__GETSESSION);
 }
 
+static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
+{
+        selinux_get_task_sid(p, secid);
+}
+
 static int selinux_task_setgroups(struct group_info *group_info)
 {
         /* See the comment for setuid above. */
@@ -2665,6 +2757,11 @@ static int selinux_task_setioprio(struct task_struct *p, int ioprio)
         return task_has_perm(current, p, PROCESS__SETSCHED);
 }
 
+static int selinux_task_getioprio(struct task_struct *p)
+{
+        return task_has_perm(current, p, PROCESS__GETSCHED);
+}
+
 static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim)
 {
         struct rlimit *old_rlim = current->signal->rlim + resource;
@@ -2699,12 +2796,14 @@ static int selinux_task_movememory(struct task_struct *p)
         return task_has_perm(current, p, PROCESS__SETSCHED);
 }
 
-static int selinux_task_kill(struct task_struct *p, struct siginfo *info, int sig)
+static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
+                                int sig, u32 secid)
 {
         u32 perm;
         int rc;
+        struct task_security_struct *tsec;
 
-        rc = secondary_ops->task_kill(p, info, sig);
+        rc = secondary_ops->task_kill(p, info, sig, secid);
         if (rc)
                 return rc;
 
@@ -2715,8 +2814,12 @@ static int selinux_task_kill(struct task_struct *p, struct siginfo *info, int si
                 perm = PROCESS__SIGNULL; /* null signal; existence test */
         else
                 perm = signal_to_av(sig);
-
-        return task_has_perm(current, p, perm);
+        tsec = p->security;
+        if (secid)
+                rc = avc_has_perm(secid, tsec->sid, SECCLASS_PROCESS, perm, NULL);
+        else
+                rc = task_has_perm(current, p, perm);
+        return rc;
 }
 
 static int selinux_task_prctl(int option,
@@ -3420,7 +3523,13 @@ out:
 static int selinux_socket_getpeersec_dgram(struct sk_buff *skb, char **secdata, u32 *seclen)
 {
         int err = 0;
-        u32 peer_sid = selinux_socket_getpeer_dgram(skb);
+        u32 peer_sid;
+
+        if (skb->sk->sk_family == PF_UNIX)
+                selinux_get_inode_sid(SOCK_INODE(skb->sk->sk_socket),
+                                      &peer_sid);
+        else
+                peer_sid = selinux_socket_getpeer_dgram(skb);
 
         if (peer_sid == SECSID_NULL)
                 return -EINVAL;
@@ -3432,8 +3541,6 @@ static int selinux_socket_getpeersec_dgram(struct sk_buff *skb, char **secdata,
         return 0;
 }
 
-
-
 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
 {
         return sk_alloc_security(sk, family, priority);
@@ -3641,32 +3748,32 @@ static unsigned int selinux_ipv6_postroute_last(unsigned int hooknum,
 
 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
 {
-        struct task_security_struct *tsec;
-        struct av_decision avd;
         int err;
 
         err = secondary_ops->netlink_send(sk, skb);
         if (err)
                 return err;
 
-        tsec = current->security;
-
-        avd.allowed = 0;
-        avc_has_perm_noaudit(tsec->sid, tsec->sid,
-                                SECCLASS_CAPABILITY, ~0, &avd);
-        cap_mask(NETLINK_CB(skb).eff_cap, avd.allowed);
-
         if (policydb_loaded_version >= POLICYDB_VERSION_NLCLASS)
                 err = selinux_nlmsg_perm(sk, skb);
 
         return err;
 }
 
-static int selinux_netlink_recv(struct sk_buff *skb)
+static int selinux_netlink_recv(struct sk_buff *skb, int capability)
 {
-        if (!cap_raised(NETLINK_CB(skb).eff_cap, CAP_NET_ADMIN))
-                return -EPERM;
-        return 0;
+        int err;
+        struct avc_audit_data ad;
+
+        err = secondary_ops->netlink_recv(skb, capability);
+        if (err)
+                return err;
+
+        AVC_AUDIT_DATA_INIT(&ad, CAP);
+        ad.u.cap = capability;
+
+        return avc_has_perm(NETLINK_CB(skb).sid, NETLINK_CB(skb).sid,
+                            SECCLASS_CAPABILITY, CAP_TO_MASK(capability), &ad);
 }
 
 static int ipc_alloc_security(struct task_struct *task,
@@ -4429,9 +4536,11 @@ static struct security_operations selinux_ops = {
         .task_setpgid =                 selinux_task_setpgid,
         .task_getpgid =                 selinux_task_getpgid,
         .task_getsid =                  selinux_task_getsid,
+        .task_getsecid =                selinux_task_getsecid,
         .task_setgroups =               selinux_task_setgroups,
         .task_setnice =                 selinux_task_setnice,
         .task_setioprio =               selinux_task_setioprio,
+        .task_getioprio =               selinux_task_getioprio,
         .task_setrlimit =               selinux_task_setrlimit,
         .task_setscheduler =            selinux_task_setscheduler,
         .task_getscheduler =            selinux_task_getscheduler,