Go to file
Andrey Konovalov d12d9ad816 kasan, mm: optimize krealloc poisoning
Currently, krealloc() always calls ksize(), which unpoisons the whole
object including the redzone.  This is inefficient, as kasan_krealloc()
repoisons the redzone for objects that fit into the same buffer.

This patch changes krealloc() instrumentation to use uninstrumented
__ksize() that doesn't unpoison the memory.  Instead, kasan_kreallos() is
changed to unpoison the memory excluding the redzone.

For objects that don't fit into the old allocation, this patch disables
KASAN accessibility checks when copying memory into a new object instead
of unpoisoning it.

Link: https://lkml.kernel.org/r/9bef90327c9cb109d736c40115684fd32f49e6b0.1612546384.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Branislav Rankov <Branislav.Rankov@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-02-26 09:41:03 -08:00
Documentation kfence: report sensitive information based on no_hash_pointers 2021-02-26 09:41:02 -08:00
LICENSES LICENSES: Add the CC-BY-4.0 license 2020-12-08 10:33:27 -07:00
arch kfence: add test suite 2021-02-26 09:41:02 -08:00
block for-5.12/block-ipi-2021-02-21 2021-02-22 10:53:05 -08:00
certs certs: Replace K{U,G}IDT_INIT() with GLOBAL_ROOT_{U,G}ID 2021-01-21 16:16:10 +00:00
crypto Keyrings miscellany 2021-02-23 16:09:23 -08:00
drivers zsmalloc: account the number of compacted pages correctly 2021-02-26 09:41:01 -08:00
fs iomap: use mapping_seek_hole_data 2021-02-26 09:40:59 -08:00
include kasan: unify large kfree checks 2021-02-26 09:41:03 -08:00
init mm: add Kernel Electric-Fence infrastructure 2021-02-26 09:41:02 -08:00
ipc fs: make helpers idmap mount aware 2021-01-24 14:27:20 +01:00
kernel tracing: add error_report_end trace point 2021-02-26 09:41:02 -08:00
lib kasan, mm: fail krealloc on freed objects 2021-02-26 09:41:03 -08:00
mm kasan, mm: optimize krealloc poisoning 2021-02-26 09:41:03 -08:00
net idmapped-mounts-v5.12 2021-02-23 13:39:45 -08:00
samples Char/Misc driver patches for 5.12-rc1 2021-02-24 10:25:37 -08:00
scripts Kbuild updates for v5.12 2021-02-25 10:17:31 -08:00
security Keyrings miscellany 2021-02-23 16:09:23 -08:00
sound ARM updates for 5.12-rc1: 2021-02-22 14:27:07 -08:00
tools Rework of the X86 irq stack handling: 2021-02-24 16:32:23 -08:00
usr Kbuild updates for v5.12 2021-02-25 10:17:31 -08:00
virt KVM/arm64 fixes for 5.11, take #2 2021-02-12 14:07:39 +00:00
.clang-format cxl for 5.12 2021-02-24 09:38:36 -08:00
.cocciconfig
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore clang-lto series for v5.12-rc1 2021-02-23 09:28:51 -08:00
.mailmap Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2021-02-21 17:23:56 -08:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS CREDITS: update email address and home address 2021-01-27 21:03:50 +02:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS MAINTAINERS: add entry for KFENCE 2021-02-26 09:41:02 -08:00
Makefile Kbuild updates for v5.12 2021-02-25 10:17:31 -08:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

README

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.