[PATCH 0/3][RESEND] add support for never printing hashed addresses

From: Timur Tabi
Date: Wed Feb 10 2021 - 00:19:10 EST


[accidentally sent from the wrong email address, so resending]

[The list of email addresses on CC: is getting quite lengthy,
so I hope I've included everyone.]

Although hashing addresses printed via printk does make the
kernel more secure, it interferes with debugging, especially
with some functions like print_hex_dump() which always uses
hashed addresses.

To avoid having to choose between %p and %px, it's easier to
add a kernel command line that treats all %p as %px. This
encourages developers to use %p more without making debugging
more difficult.

Patches #1 and #2 upgrade the kselftest framework so that
it can report on tests that were skipped outright. This
is needed for the test_printf module which will now skip
%p hashing tests if hashing is disabled.

Patch #2 upgrades the printf library to check the command
line. It also updates test_printf().

Timur Tabi (3):
lib/test_printf: use KSTM_MODULE_GLOBALS macro
kselftest: add support for skipped tests
[v2] lib/vsprintf: make-printk-non-secret printks all addresses as
unhashed

.../admin-guide/kernel-parameters.txt | 15 +++++++
lib/test_printf.c | 12 +++++-
lib/vsprintf.c | 40 ++++++++++++++++++-
tools/testing/selftests/kselftest_module.h | 18 ++++++---
4 files changed, 75 insertions(+), 10 deletions(-)

--
2.25.1