[GIT PULL] kallsyms_show_value-fix updates for v5.9-rc1

From: Kees Cook
Date: Fri Aug 07 2020 - 15:55:36 EST

Hi Linus,

Please pull this fix to my kallsyms_show_value() refactoring for
v5.9-rc1. About a month after the original refactoring landed, 0day
noticed that there was a path through the kernfs binattr read handlers
that did not have PAGE_SIZEd buffers, and the module "sections" read
handler made a bad assumption about this, resulting in it stomping on
memory when reached through small-sized splice() calls. I've added a set
of tests to find these kinds of regressions more quickly in the future
as well.



The following changes since commit bcf876870b95592b52519ed4aafcf9d95999bc9c:

Linux 5.8 (2020-08-02 14:21:45 -0700)

are available in the Git repository at:

https://git.kernel.org/pub/scm/linux/kernel/git/kees/linux.git tags/kallsyms_show_value-fix-v5.9-rc1

for you to fetch changes up to 9af47666cb0f331bfcd76799ee368cdfcb00882c:

selftests: splice: Check behavior of full and short splices (2020-08-07 10:50:11 -0700)

Fix sysfs module section output overflow

Kees Cook (2):
module: Correctly truncate sysfs sections output
selftests: splice: Check behavior of full and short splices

kernel/module.c | 22 +++++++--
tools/testing/selftests/splice/.gitignore | 1 +
tools/testing/selftests/splice/Makefile | 4 +-
tools/testing/selftests/splice/config | 1 +
tools/testing/selftests/splice/settings | 1 +
.../testing/selftests/splice/short_splice_read.sh | 56 +++++++++++++++++++++
tools/testing/selftests/splice/splice_read.c | 57 ++++++++++++++++++++++
7 files changed, 137 insertions(+), 5 deletions(-)
create mode 100644 tools/testing/selftests/splice/config
create mode 100644 tools/testing/selftests/splice/settings
create mode 100755 tools/testing/selftests/splice/short_splice_read.sh
create mode 100644 tools/testing/selftests/splice/splice_read.c

Kees Cook