1 files changed, 20 insertions, 26 deletions

diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c
index e79f170fa79b..43b3ca5e045f 100644
--- a/fs/pstore/platform.c
+++ b/fs/pstore/platform.c
@@ -635,33 +635,27 @@ static void pstore_unregister_console(void) {}
 static int pstore_write_user_compat(struct pstore_record *record,
                                     const char __user *buf)
 {
-        unsigned long flags = 0;
-        size_t i, bufsize, total_size = record->size;
-        long ret = 0;
-
-        if (unlikely(!access_ok(VERIFY_READ, buf, total_size)))
-                return -EFAULT;
-        bufsize = total_size;
-        if (bufsize > psinfo->bufsize)
-                bufsize = psinfo->bufsize;
-        record->buf = psinfo->buf;
-        spin_lock_irqsave(&psinfo->buf_lock, flags);
-        for (i = 0; i < total_size; ) {
-                size_t c = min(total_size - i, bufsize);
-
-                ret = __copy_from_user(record->buf, buf + i, c);
-                if (unlikely(ret != 0)) {
-                        ret = -EFAULT;
-                        break;
-                }
-                record->size = c;
-                ret = record->psi->write(record);
-                if (unlikely(ret < 0))
-                        break;
-                i += c;
+        int ret = 0;
+
+        if (record->buf)
+                return -EINVAL;
+
+        record->buf = kmalloc(record->size, GFP_KERNEL);
+        if (!record->buf)
+                return -ENOMEM;
+
+        if (unlikely(copy_from_user(record->buf, buf, record->size))) {
+                ret = -EFAULT;
+                goto out;
         }
-        spin_unlock_irqrestore(&psinfo->buf_lock, flags);
-        return unlikely(ret < 0) ? ret : total_size;
+
+        ret = record->psi->write(record);
+
+out:
+        kfree(record->buf);
+        record->buf = NULL;
+
+        return unlikely(ret < 0) ? ret : record->size;
 }
 
 /*