1 files changed, 98 insertions, 36 deletions

diff --git a/fs/sysfs/inode.c b/fs/sysfs/inode.c
index 555f0ff988df..2b6a8d9de73d 100644
--- a/fs/sysfs/inode.c
+++ b/fs/sysfs/inode.c
@@ -18,6 +18,8 @@
 #include <linux/capability.h>
 #include <linux/errno.h>
 #include <linux/sched.h>
+#include <linux/xattr.h>
+#include <linux/security.h>
 #include "sysfs.h"
 
 extern struct super_block * sysfs_sb;
@@ -35,6 +37,7 @@ static struct backing_dev_info sysfs_backing_dev_info = {
 
 static const struct inode_operations sysfs_inode_operations ={
         .setattr        = sysfs_setattr,
+        .setxattr       = sysfs_setxattr,
 };
 
 int __init sysfs_inode_init(void)
@@ -42,18 +45,37 @@ int __init sysfs_inode_init(void)
         return bdi_init(&sysfs_backing_dev_info);
 }
 
+struct sysfs_inode_attrs *sysfs_init_inode_attrs(struct sysfs_dirent *sd)
+{
+        struct sysfs_inode_attrs *attrs;
+        struct iattr *iattrs;
+
+        attrs = kzalloc(sizeof(struct sysfs_inode_attrs), GFP_KERNEL);
+        if (!attrs)
+                return NULL;
+        iattrs = &attrs->ia_iattr;
+
+        /* assign default attributes */
+        iattrs->ia_mode = sd->s_mode;
+        iattrs->ia_uid = 0;
+        iattrs->ia_gid = 0;
+        iattrs->ia_atime = iattrs->ia_mtime = iattrs->ia_ctime = CURRENT_TIME;
+
+        return attrs;
+}
 int sysfs_setattr(struct dentry * dentry, struct iattr * iattr)
 {
         struct inode * inode = dentry->d_inode;
         struct sysfs_dirent * sd = dentry->d_fsdata;
-        struct iattr * sd_iattr;
+        struct sysfs_inode_attrs *sd_attrs;
+        struct iattr *iattrs;
         unsigned int ia_valid = iattr->ia_valid;
         int error;
 
         if (!sd)
                 return -EINVAL;
 
-        sd_iattr = sd->s_iattr;
+        sd_attrs = sd->s_iattr;
 
         error = inode_change_ok(inode, iattr);
         if (error)
@@ -65,42 +87,77 @@ int sysfs_setattr(struct dentry * dentry, struct iattr * iattr)
         if (error)
                 return error;
 
-        if (!sd_iattr) {
+        if (!sd_attrs) {
                 /* setting attributes for the first time, allocate now */
-                sd_iattr = kzalloc(sizeof(struct iattr), GFP_KERNEL);
-                if (!sd_iattr)
+                sd_attrs = sysfs_init_inode_attrs(sd);
+                if (!sd_attrs)
                         return -ENOMEM;
-                /* assign default attributes */
-                sd_iattr->ia_mode = sd->s_mode;
-                sd_iattr->ia_uid = 0;
-                sd_iattr->ia_gid = 0;
-                sd_iattr->ia_atime = sd_iattr->ia_mtime = sd_iattr->ia_ctime = CURRENT_TIME;
-                sd->s_iattr = sd_iattr;
+                sd->s_iattr = sd_attrs;
+        } else {
+                /* attributes were changed at least once in past */
+                iattrs = &sd_attrs->ia_iattr;
+
+                if (ia_valid & ATTR_UID)
+                        iattrs->ia_uid = iattr->ia_uid;
+                if (ia_valid & ATTR_GID)
+                        iattrs->ia_gid = iattr->ia_gid;
+                if (ia_valid & ATTR_ATIME)
+                        iattrs->ia_atime = timespec_trunc(iattr->ia_atime,
+                                        inode->i_sb->s_time_gran);
+                if (ia_valid & ATTR_MTIME)
+                        iattrs->ia_mtime = timespec_trunc(iattr->ia_mtime,
+                                        inode->i_sb->s_time_gran);
+                if (ia_valid & ATTR_CTIME)
+                        iattrs->ia_ctime = timespec_trunc(iattr->ia_ctime,
+                                        inode->i_sb->s_time_gran);
+                if (ia_valid & ATTR_MODE) {
+                        umode_t mode = iattr->ia_mode;
+
+                        if (!in_group_p(inode->i_gid) && !capable(CAP_FSETID))
+                                mode &= ~S_ISGID;
+                        iattrs->ia_mode = sd->s_mode = mode;
+                }
         }
+        return error;
+}
 
-        /* attributes were changed atleast once in past */
-
-        if (ia_valid & ATTR_UID)
-                sd_iattr->ia_uid = iattr->ia_uid;
-        if (ia_valid & ATTR_GID)
-                sd_iattr->ia_gid = iattr->ia_gid;
-        if (ia_valid & ATTR_ATIME)
-                sd_iattr->ia_atime = timespec_trunc(iattr->ia_atime,
-                                                inode->i_sb->s_time_gran);
-        if (ia_valid & ATTR_MTIME)
-                sd_iattr->ia_mtime = timespec_trunc(iattr->ia_mtime,
-                                                inode->i_sb->s_time_gran);
-        if (ia_valid & ATTR_CTIME)
-                sd_iattr->ia_ctime = timespec_trunc(iattr->ia_ctime,
-                                                inode->i_sb->s_time_gran);
-        if (ia_valid & ATTR_MODE) {
-                umode_t mode = iattr->ia_mode;
-
-                if (!in_group_p(inode->i_gid) && !capable(CAP_FSETID))
-                        mode &= ~S_ISGID;
-                sd_iattr->ia_mode = sd->s_mode = mode;
-        }
+int sysfs_setxattr(struct dentry *dentry, const char *name, const void *value,
+                size_t size, int flags)
+{
+        struct sysfs_dirent *sd = dentry->d_fsdata;
+        struct sysfs_inode_attrs *iattrs;
+        void *secdata;
+        int error;
+        u32 secdata_len = 0;
+
+        if (!sd)
+                return -EINVAL;
+        if (!sd->s_iattr)
+                sd->s_iattr = sysfs_init_inode_attrs(sd);
+        if (!sd->s_iattr)
+                return -ENOMEM;
+
+        iattrs = sd->s_iattr;
+
+        if (!strncmp(name, XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN)) {
+                const char *suffix = name + XATTR_SECURITY_PREFIX_LEN;
+                error = security_inode_setsecurity(dentry->d_inode, suffix,
+                                                value, size, flags);
+                if (error)
+                        goto out;
+                error = security_inode_getsecctx(dentry->d_inode,
+                                                &secdata, &secdata_len);
+                if (error)
+                        goto out;
+                if (iattrs->ia_secdata)
+                        security_release_secctx(iattrs->ia_secdata,
+                                                iattrs->ia_secdata_len);
+                iattrs->ia_secdata = secdata;
+                iattrs->ia_secdata_len = secdata_len;
 
+        } else
+                return -EINVAL;
+out:
         return error;
 }
 
@@ -146,6 +203,7 @@ static int sysfs_count_nlink(struct sysfs_dirent *sd)
 static void sysfs_init_inode(struct sysfs_dirent *sd, struct inode *inode)
 {
         struct bin_attribute *bin_attr;
+        struct sysfs_inode_attrs *iattrs;
 
         inode->i_private = sysfs_get(sd);
         inode->i_mapping->a_ops = &sysfs_aops;
@@ -154,16 +212,20 @@ static void sysfs_init_inode(struct sysfs_dirent *sd, struct inode *inode)
         inode->i_ino = sd->s_ino;
         lockdep_set_class(&inode->i_mutex, &sysfs_inode_imutex_key);
 
-        if (sd->s_iattr) {
+        iattrs = sd->s_iattr;
+        if (iattrs) {
                 /* sysfs_dirent has non-default attributes
                  * get them for the new inode from persistent copy
                  * in sysfs_dirent
                  */
-                set_inode_attr(inode, sd->s_iattr);
+                set_inode_attr(inode, &iattrs->ia_iattr);
+                if (iattrs->ia_secdata)
+                        security_inode_notifysecctx(inode,
+                                                iattrs->ia_secdata,
+                                                iattrs->ia_secdata_len);
         } else
                 set_default_inode_attr(inode, sd->s_mode);
 
-
         /* initialize inode according to type */
         switch (sysfs_type(sd)) {
         case SYSFS_DIR: