2 files changed, 99 insertions, 81 deletions

diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 75c2e99bfb81..4bf4807f2d44 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -443,8 +443,7 @@ out:
  * mount options, or whatever.
  */
 static int selinux_get_mnt_opts(const struct super_block *sb,
-                                char ***mount_options, int **mnt_opts_flags,
-                                int *num_opts)
+                                struct security_mnt_opts *opts)
 {
         int rc = 0, i;
         struct superblock_security_struct *sbsec = sb->s_security;
@@ -452,9 +451,7 @@ static int selinux_get_mnt_opts(const struct super_block *sb,
         u32 len;
         char tmp;
 
-        *num_opts = 0;
-        *mount_options = NULL;
-        *mnt_opts_flags = NULL;
+        security_init_mnt_opts(opts);
 
         if (!sbsec->initialized)
                 return -EINVAL;
@@ -470,18 +467,18 @@ static int selinux_get_mnt_opts(const struct super_block *sb,
         /* count the number of mount options for this sb */
         for (i = 0; i < 8; i++) {
                 if (tmp & 0x01)
-                        (*num_opts)++;
+                        opts->num_mnt_opts++;
                 tmp >>= 1;
         }
 
-        *mount_options = kcalloc(*num_opts, sizeof(char *), GFP_ATOMIC);
-        if (!*mount_options) {
+        opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
+        if (!opts->mnt_opts) {
                 rc = -ENOMEM;
                 goto out_free;
         }
 
-        *mnt_opts_flags = kcalloc(*num_opts, sizeof(int), GFP_ATOMIC);
-        if (!*mnt_opts_flags) {
+        opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
+        if (!opts->mnt_opts_flags) {
                 rc = -ENOMEM;
                 goto out_free;
         }
@@ -491,22 +488,22 @@ static int selinux_get_mnt_opts(const struct super_block *sb,
                 rc = security_sid_to_context(sbsec->sid, &context, &len);
                 if (rc)
                         goto out_free;
-                (*mount_options)[i] = context;
-                (*mnt_opts_flags)[i++] = FSCONTEXT_MNT;
+                opts->mnt_opts[i] = context;
+                opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
         }
         if (sbsec->flags & CONTEXT_MNT) {
                 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
                 if (rc)
                         goto out_free;
-                (*mount_options)[i] = context;
-                (*mnt_opts_flags)[i++] = CONTEXT_MNT;
+                opts->mnt_opts[i] = context;
+                opts->mnt_opts_flags[i++] = CONTEXT_MNT;
         }
         if (sbsec->flags & DEFCONTEXT_MNT) {
                 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
                 if (rc)
                         goto out_free;
-                (*mount_options)[i] = context;
-                (*mnt_opts_flags)[i++] = DEFCONTEXT_MNT;
+                opts->mnt_opts[i] = context;
+                opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
         }
         if (sbsec->flags & ROOTCONTEXT_MNT) {
                 struct inode *root = sbsec->sb->s_root->d_inode;
@@ -515,24 +512,16 @@ static int selinux_get_mnt_opts(const struct super_block *sb,
                 rc = security_sid_to_context(isec->sid, &context, &len);
                 if (rc)
                         goto out_free;
-                (*mount_options)[i] = context;
-                (*mnt_opts_flags)[i++] = ROOTCONTEXT_MNT;
+                opts->mnt_opts[i] = context;
+                opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
         }
 
-        BUG_ON(i != *num_opts);
+        BUG_ON(i != opts->num_mnt_opts);
 
         return 0;
 
 out_free:
-        /* don't leak context string if security_sid_to_context had an error */
-        if (*mount_options && i)
-                for (; i > 0; i--)
-                        kfree((*mount_options)[i-1]);
-        kfree(*mount_options);
-        *mount_options = NULL;
-        kfree(*mnt_opts_flags);
-        *mnt_opts_flags = NULL;
-        *num_opts = 0;
+        security_free_mnt_opts(opts);
         return rc;
 }
 
@@ -553,12 +542,13 @@ static int bad_option(struct superblock_security_struct *sbsec, char flag,
                         return 1;
         return 0;
 }
+
 /*
  * Allow filesystems with binary mount data to explicitly set mount point
  * labeling information.
  */
-static int selinux_set_mnt_opts(struct super_block *sb, char **mount_options,
-                                int *flags, int num_opts)
+static int selinux_set_mnt_opts(struct super_block *sb,
+                                struct security_mnt_opts *opts)
 {
         int rc = 0, i;
         struct task_security_struct *tsec = current->security;
@@ -568,6 +558,9 @@ static int selinux_set_mnt_opts(struct super_block *sb, char **mount_options,
         struct inode_security_struct *root_isec = inode->i_security;
         u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
         u32 defcontext_sid = 0;
+        char **mount_options = opts->mnt_opts;
+        int *flags = opts->mnt_opts_flags;
+        int num_opts = opts->num_mnt_opts;
 
         mutex_lock(&sbsec->lock);
 
@@ -589,6 +582,21 @@ static int selinux_set_mnt_opts(struct super_block *sb, char **mount_options,
         }
 
         /*
+         * Binary mount data FS will come through this function twice.  Once
+         * from an explicit call and once from the generic calls from the vfs.
+         * Since the generic VFS calls will not contain any security mount data
+         * we need to skip the double mount verification.
+         *
+         * This does open a hole in which we will not notice if the first
+         * mount using this sb set explict options and a second mount using
+         * this sb does not set any security options.  (The first options
+         * will be used for both mounts)
+         */
+        if (sbsec->initialized && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
+            && (num_opts == 0))
+                goto out;
+
+        /*
          * parse the mount options, check if they are valid sids.
          * also check if someone is trying to mount the same sb more
          * than once with different security options.
@@ -792,43 +800,14 @@ static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
         mutex_unlock(&newsbsec->lock);
 }
 
-/*
- * string mount options parsing and call set the sbsec
- */
-static int superblock_doinit(struct super_block *sb, void *data)
+int selinux_parse_opts_str(char *options, struct security_mnt_opts *opts)
 {
+        char *p;
         char *context = NULL, *defcontext = NULL;
         char *fscontext = NULL, *rootcontext = NULL;
-        int rc = 0;
-        char *p, *options = data;
-        /* selinux only know about a fixed number of mount options */
-        char *mnt_opts[NUM_SEL_MNT_OPTS];
-        int mnt_opts_flags[NUM_SEL_MNT_OPTS], num_mnt_opts = 0;
-
-        if (!data)
-                goto out;
+        int rc, num_mnt_opts = 0;
 
-        /* with the nfs patch this will become a goto out; */
-        if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) {
-                const char *name = sb->s_type->name;
-                /* NFS we understand. */
-                if (!strcmp(name, "nfs")) {
-                        struct nfs_mount_data *d = data;
-
-                        if (d->version !=  NFS_MOUNT_VERSION)
-                                goto out;
-
-                        if (d->context[0]) {
-                                context = kstrdup(d->context, GFP_KERNEL);
-                                if (!context) {
-                                        rc = -ENOMEM;
-                                        goto out;
-                                }
-                        }
-                        goto build_flags;
-                } else
-                        goto out;
-        }
+        opts->num_mnt_opts = 0;
 
         /* Standard string-based options. */
         while ((p = strsep(&options, "|")) != NULL) {
@@ -901,26 +880,37 @@ static int superblock_doinit(struct super_block *sb, void *data)
                 }
         }
 
-build_flags:
+        rc = -ENOMEM;
+        opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
+        if (!opts->mnt_opts)
+                goto out_err;
+
+        opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
+        if (!opts->mnt_opts_flags) {
+                kfree(opts->mnt_opts);
+                goto out_err;
+        }
+
         if (fscontext) {
-                mnt_opts[num_mnt_opts] = fscontext;
-                mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
+                opts->mnt_opts[num_mnt_opts] = fscontext;
+                opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
         }
         if (context) {
-                mnt_opts[num_mnt_opts] = context;
-                mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
+                opts->mnt_opts[num_mnt_opts] = context;
+                opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
         }
         if (rootcontext) {
-                mnt_opts[num_mnt_opts] = rootcontext;
-                mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
+                opts->mnt_opts[num_mnt_opts] = rootcontext;
+                opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
         }
         if (defcontext) {
-                mnt_opts[num_mnt_opts] = defcontext;
-                mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
+                opts->mnt_opts[num_mnt_opts] = defcontext;
+                opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
         }
 
-out:
-        rc = selinux_set_mnt_opts(sb, mnt_opts, mnt_opts_flags, num_mnt_opts);
+        opts->num_mnt_opts = num_mnt_opts;
+        return 0;
+
 out_err:
         kfree(context);
         kfree(defcontext);
@@ -928,6 +918,33 @@ out_err:
         kfree(rootcontext);
         return rc;
 }
+/*
+ * string mount options parsing and call set the sbsec
+ */
+static int superblock_doinit(struct super_block *sb, void *data)
+{
+        int rc = 0;
+        char *options = data;
+        struct security_mnt_opts opts;
+
+        security_init_mnt_opts(&opts);
+
+        if (!data)
+                goto out;
+
+        BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
+
+        rc = selinux_parse_opts_str(options, &opts);
+        if (rc)
+                goto out_err;
+
+out:
+        rc = selinux_set_mnt_opts(sb, &opts);
+
+out_err:
+        security_free_mnt_opts(&opts);
+        return rc;
+}
 
 static inline u16 inode_mode_to_security_class(umode_t mode)
 {
@@ -2253,7 +2270,7 @@ static inline void take_selinux_option(char **to, char *from, int *first,
         }
 }
 
-static int selinux_sb_copy_data(struct file_system_type *type, void *orig, void *copy)
+static int selinux_sb_copy_data(char *orig, char *copy)
 {
         int fnosec, fsec, rc = 0;
         char *in_save, *in_curr, *in_end;
@@ -2263,12 +2280,6 @@ static int selinux_sb_copy_data(struct file_system_type *type, void *orig, void
         in_curr = orig;
         sec_curr = copy;
 
-        /* Binary mount data: just copy */
-        if (type->fs_flags & FS_BINARY_MOUNTDATA) {
-                copy_page(sec_curr, in_curr);
-                goto out;
-        }
-
         nosec = (char *)get_zeroed_page(GFP_KERNEL);
         if (!nosec) {
                 rc = -ENOMEM;
@@ -5251,6 +5262,8 @@ static struct security_operations selinux_ops = {
         .sb_get_mnt_opts =              selinux_get_mnt_opts,
         .sb_set_mnt_opts =              selinux_set_mnt_opts,
         .sb_clone_mnt_opts =            selinux_sb_clone_mnt_opts,
+        .sb_parse_opts_str =            selinux_parse_opts_str,
+
 
         .inode_alloc_security =         selinux_inode_alloc_security,
         .inode_free_security =          selinux_inode_free_security,
diff --git a/security/selinux/include/security.h b/security/selinux/include/security.h
index 837ce420d2f6..f7d2f03781f2 100644
--- a/security/selinux/include/security.h
+++ b/security/selinux/include/security.h
@@ -35,6 +35,11 @@
 #define POLICYDB_VERSION_MAX    POLICYDB_VERSION_POLCAP
 #endif
 
+#define CONTEXT_MNT     0x01
+#define FSCONTEXT_MNT   0x02
+#define ROOTCONTEXT_MNT 0x04
+#define DEFCONTEXT_MNT  0x08
+
 struct netlbl_lsm_secattr;
 
 extern int selinux_enabled;