2 files changed, 19 insertions, 20 deletions

diff --git a/drivers/char/mem.c b/drivers/char/mem.c
index be832b6f8279..48788db4e280 100644
--- a/drivers/char/mem.c
+++ b/drivers/char/mem.c
@@ -395,6 +395,7 @@ static ssize_t read_kmem(struct file *file, char __user *buf,
         unsigned long p = *ppos;
         ssize_t low_count, read, sz;
         char * kbuf; /* k-addr because vread() takes vmlist_lock rwlock */
+        int err = 0;
 
         read = 0;
         if (p < (unsigned long) high_memory) {
@@ -441,12 +442,16 @@ static ssize_t read_kmem(struct file *file, char __user *buf,
                         return -ENOMEM;
                 while (count > 0) {
                         sz = size_inside_page(p, count);
+                        if (!is_vmalloc_or_module_addr((void *)p)) {
+                                err = -ENXIO;
+                                break;
+                        }
                         sz = vread(kbuf, (char *)p, sz);
                         if (!sz)
                                 break;
                         if (copy_to_user(buf, kbuf, sz)) {
-                                free_page((unsigned long)kbuf);
-                                return -EFAULT;
+                                err = -EFAULT;
+                                break;
                         }
                         count -= sz;
                         buf += sz;
@@ -455,8 +460,8 @@ static ssize_t read_kmem(struct file *file, char __user *buf,
                 }
                 free_page((unsigned long)kbuf);
         }
-        *ppos = p;
-        return read;
+        *ppos = p;
+        return read ? read : err;
 }
 
 
@@ -520,6 +525,7 @@ static ssize_t write_kmem(struct file * file, const char __user * buf,
         ssize_t wrote = 0;
         ssize_t virtr = 0;
         char * kbuf; /* k-addr because vwrite() takes vmlist_lock rwlock */
+        int err = 0;
 
         if (p < (unsigned long) high_memory) {
                 unsigned long to_write = min_t(unsigned long, count,
@@ -540,14 +546,16 @@ static ssize_t write_kmem(struct file * file, const char __user * buf,
                         unsigned long sz = size_inside_page(p, count);
                         unsigned long n;
 
+                        if (!is_vmalloc_or_module_addr((void *)p)) {
+                                err = -ENXIO;
+                                break;
+                        }
                         n = copy_from_user(kbuf, buf, sz);
                         if (n) {
-                                if (wrote + virtr)
-                                        break;
-                                free_page((unsigned long)kbuf);
-                                return -EFAULT;
+                                err = -EFAULT;
+                                break;
                         }
-                        sz = vwrite(kbuf, (char *)p, sz);
+                        vwrite(kbuf, (char *)p, sz);
                         count -= sz;
                         buf += sz;
                         virtr += sz;
@@ -556,8 +564,8 @@ static ssize_t write_kmem(struct file * file, const char __user * buf,
                 free_page((unsigned long)kbuf);
         }
 
-        *ppos = p;
-        return virtr + wrote;
+        *ppos = p;
+        return virtr + wrote ? : err;
 }
 #endif
 
diff --git a/drivers/char/random.c b/drivers/char/random.c
index 8258982b49ec..2849713d2231 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -1051,12 +1051,6 @@ random_read(struct file *file, char __user *buf, size_t nbytes, loff_t *ppos)
                                 /* like a named pipe */
         }
 
-        /*
-         * If we gave the user some bytes, update the access time.
-         */
-        if (count)
-                file_accessed(file);
-
         return (count ? count : retval);
 }
 
@@ -1107,7 +1101,6 @@ static ssize_t random_write(struct file *file, const char __user *buffer,
                             size_t count, loff_t *ppos)
 {
         size_t ret;
-        struct inode *inode = file->f_path.dentry->d_inode;
 
         ret = write_pool(&blocking_pool, buffer, count);
         if (ret)
@@ -1116,8 +1109,6 @@ static ssize_t random_write(struct file *file, const char __user *buffer,
         if (ret)
                 return ret;
 
-        inode->i_mtime = current_fs_time(inode->i_sb);
-        mark_inode_dirty(inode);
         return (ssize_t)count;
 }