linux-kernel - [PATCH v1 0/3] Switch get/put unaligned to use memcpy

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-ID: <20250617005800.1410112-1-irogers@google.com>
Date: Mon, 16 Jun 2025 17:57:57 -0700
From: Ian Rogers <irogers@...gle.com>
To: Eric Biggers <ebiggers@...gle.com>, Yuzhuo Jing <yuzhuo@...gle.com>, 
	Andy Lutomirski <luto@...nel.org>, Thomas Gleixner <tglx@...utronix.de>, 
	Vincenzo Frascino <vincenzo.frascino@....com>, Arnaldo Carvalho de Melo <acme@...hat.com>, 
	Al Viro <viro@...iv.linux.org.uk>, Christophe Leroy <christophe.leroy@...roup.eu>, 
	"Jason A. Donenfeld" <Jason@...c4.com>, linux-kernel@...r.kernel.org, 
	linux-perf-users@...r.kernel.org
Cc: Ian Rogers <irogers@...gle.com>
Subject: [PATCH v1 0/3] Switch get/put unaligned to use memcpy

The existing type punning approach with packed structs requires
 -fno-strict-aliasing to be passed to the compiler for
correctness. This is true in the kernel tree but not in the tools
directory resulting in this suggested patch from Eric Biggers
 <ebiggers@...gle.com>:
https://lore.kernel.org/lkml/20250614044133.660848-2-ebiggers@kernel.org/

Requiring -fno-strict-aliasing seems unfortunate and so this patch
makes the unaligned code work via memcpy for type punning rather than
the packed attribute.

Ian Rogers (3):
  vdso: Switch get/put unaligned from packed struct to memcpy
  tools headers: Update the linux/unaligned.h copy with the kernel
    sources
  tools headers: Remove unneeded ignoring of warnings in unaligned.h

 include/vdso/unaligned.h        | 48 ++++++++++++++++++++++++++++-----
 tools/include/linux/unaligned.h |  4 ---
 tools/include/vdso/unaligned.h  | 48 ++++++++++++++++++++++++++++-----
 3 files changed, 84 insertions(+), 16 deletions(-)

-- 
2.50.0.rc2.692.g299adb8693-goog