debugfs: Add read-only/write-only x64 file ops

There aren't any read-only or write-only x64 file ops, but there is a caller of debugfs_create_x64() that calls it with mode equal to S_IRUGO. This leads to the possibility of userspace modifying the file, so let's use the newly created debugfs_create_mode() helper here to fix this. Signed-off-by: Stephen Boyd <[email protected]> Reviewed-by: Viresh Kumar <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
josf · Oct 18, 2015 · 82b7d4f · 82b7d4f
1 parent b97f679
commit 82b7d4f
Showing 1 changed file with 4 additions and 1 deletion.
diff --git a/fs/debugfs/file.c b/fs/debugfs/file.c
@@ -256,6 +256,8 @@ DEFINE_SIMPLE_ATTRIBUTE(fops_x32_ro, debugfs_u32_get, NULL, "0x%08llx\n");
 DEFINE_SIMPLE_ATTRIBUTE(fops_x32_wo, NULL, debugfs_u32_set, "0x%08llx\n");
 
 DEFINE_SIMPLE_ATTRIBUTE(fops_x64, debugfs_u64_get, debugfs_u64_set, "0x%016llx\n");
+DEFINE_SIMPLE_ATTRIBUTE(fops_x64_ro, debugfs_u64_get, NULL, "0x%016llx\n");
+DEFINE_SIMPLE_ATTRIBUTE(fops_x64_wo, NULL, debugfs_u64_set, "0x%016llx\n");
 
 /*
  * debugfs_create_x{8,16,32,64} - create a debugfs file that is used to read and write an unsigned {8,16,32,64}-bit value
@@ -332,7 +334,8 @@ EXPORT_SYMBOL_GPL(debugfs_create_x32);
 struct dentry *debugfs_create_x64(const char *name, umode_t mode,
 				 struct dentry *parent, u64 *value)
 {
-	return debugfs_create_file(name, mode, parent, value, &fops_x64);
+	return debugfs_create_mode(name, mode, parent, value, &fops_x64,
+				   &fops_x64_ro, &fops_x64_wo);
 }
 EXPORT_SYMBOL_GPL(debugfs_create_x64);