Update the self-protection documentation, to mention also the use of the
__wr_after_init attribute.
Signed-off-by: Igor Stoppa <[email protected]>
CC: Andy Lutomirski <[email protected]>
CC: Nadav Amit <[email protected]>
CC: Matthew Wilcox <[email protected]>
CC: Peter Zijlstra <[email protected]>
CC: Kees Cook <[email protected]>
CC: Dave Hansen <[email protected]>
CC: Mimi Zohar <[email protected]>
CC: Thiago Jung Bauermann <[email protected]>
CC: Ahmed Soliman <[email protected]>
CC: [email protected]
CC: [email protected]
CC: [email protected]
CC: [email protected]
---
Documentation/security/self-protection.rst | 14 ++++++++------
1 file changed, 8 insertions(+), 6 deletions(-)
diff --git a/Documentation/security/self-protection.rst b/Documentation/security/self-protection.rst
index f584fb74b4ff..df2614bc25b9 100644
--- a/Documentation/security/self-protection.rst
+++ b/Documentation/security/self-protection.rst
@@ -84,12 +84,14 @@ For variables that are initialized once at ``__init`` time, these can
be marked with the (new and under development) ``__ro_after_init``
attribute.
-What remains are variables that are updated rarely (e.g. GDT). These
-will need another infrastructure (similar to the temporary exceptions
-made to kernel code mentioned above) that allow them to spend the rest
-of their lifetime read-only. (For example, when being updated, only the
-CPU thread performing the update would be given uninterruptible write
-access to the memory.)
+Others, which are statically allocated, but still need to be updated
+rarely, can be marked with the ``__wr_after_init`` attribute.
+
+The update mechanism must avoid exposing the data to rogue alterations
+during the update. For example, only the CPU thread performing the update
+would be given uninterruptible write access to the memory.
+
+Currently there is no protection available for data allocated dynamically.
Segregation of kernel memory from userspace memory
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
--
2.19.1