Merge tag 'selinux-pr-20180629' of git://git.kernel.org/pub/scm/linux/kernel/git...

[sfrench/cifs-2.6.git] / Documentation / ioctl / botching-up-ioctls.txt

diff --git a/Documentation/ioctl/botching-up-ioctls.txt b/Documentation/ioctl/botching-up-ioctls.txt
index d02cfb48901c5c5c2b357822e51da3e2a0621fde..883fb034bd04af77a99a569f9dc3b85b7e7a982a 100644 (file)
--- a/Documentation/ioctl/botching-up-ioctls.txt
+++ b/Documentation/ioctl/botching-up-ioctls.txt
@@ -73,7 +73,9 @@ will have a second iteration or at least an extension for any given interface.
    future extensions is going right down the gutters since someone will submit
    an ioctl struct with random stack garbage in the yet unused parts. Which
    then bakes in the ABI that those fields can never be used for anything else
-   but garbage.
+   but garbage. This is also the reason why you must explicitly pad all
+   structures, even if you never use them in an array - the padding the compiler
+   might insert could contain garbage.
 
  * Have simple testcases for all of the above.