[00/11] treewide: address gcc-11 -Wstringop-overread warnings

From: Arnd Bergmann <arnd@arndb.de>

The coming gcc release introduces a new warning for string operations
reading beyond the end of a fixed-length object. After testing
randconfig kernels for a while, think I have patches for any such
warnings that came up on x86, arm and arm64.

Most of these warnings are false-positive ones, either gcc warning
about something that is entirely correct, or about something that
looks suspicious but turns out to be correct after all.

The two patches for the i915 driver look like something that might
be actual bugs, but I am not sure about those either.

We probably want some combination of workaround like the ones I
post here and changes to gcc to have fewer false positives in the
release. I'm posting the entire set of workaround that give me
a cleanly building kernel for reference here.

        Arnd

Arnd Bergmann (11):
  x86: compressed: avoid gcc-11 -Wstringop-overread warning
  x86: tboot: avoid Wstringop-overread-warning
  security: commoncap: fix -Wstringop-overread warning
  ath11: Wstringop-overread warning
  qnx: avoid -Wstringop-overread warning
  cgroup: fix -Wzero-length-bounds warnings
  ARM: sharpsl_param: work around -Wstringop-overread warning
  atmel: avoid gcc -Wstringop-overflow warning
  scsi: lpfc: fix gcc -Wstringop-overread warning
  drm/i915: avoid stringop-overread warning on pri_latency
  [RFC] drm/i915/dp: fix array overflow warning

 arch/arm/common/sharpsl_param.c         |  4 ++-
 arch/x86/boot/compressed/misc.c         |  2 --
 arch/x86/kernel/tboot.c                 | 44 +++++++++++++++----------
 drivers/gpu/drm/i915/display/intel_dp.c |  2 +-
 drivers/gpu/drm/i915/i915_drv.h         |  6 ++--
 drivers/net/wireless/ath/ath11k/mac.c   |  2 +-
 drivers/net/wireless/atmel/atmel.c      | 25 ++++++++------
 drivers/scsi/lpfc/lpfc_attr.c           |  6 ++--
 fs/qnx4/dir.c                           | 11 +++----
 kernel/cgroup/cgroup.c                  | 15 +++++++--
 security/commoncap.c                    |  2 +-
 11 files changed, 69 insertions(+), 50 deletions(-)

Cc: x86@kernel.org
Cc: Ning Sun <ning.sun@intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Kalle Valo <kvalo@codeaurora.org>
Cc: Simon Kelley <simon@thekelleys.org.uk>
Cc: James Smart <james.smart@broadcom.com>
Cc: "James E.J. Bottomley" <jejb@linux.ibm.com>
Cc: Anders Larsen <al@alarsen.net>
Cc: Tejun Heo <tj@kernel.org>
Cc: Serge Hallyn <serge@hallyn.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Cc: tboot-devel@lists.sourceforge.net
Cc: intel-gfx@lists.freedesktop.org
Cc: dri-devel@lists.freedesktop.org
Cc: ath11k@lists.infradead.org
Cc: linux-wireless@vger.kernel.org
Cc: netdev@vger.kernel.org
Cc: linux-scsi@vger.kernel.org
Cc: cgroups@vger.kernel.org
Cc: linux-security-module@vger.kernel.org

On Mon, 22 Mar 2021 17:02:38 +0100, Arnd Bergmann wrote:

> The coming gcc release introduces a new warning for string operations
> reading beyond the end of a fixed-length object. After testing
> randconfig kernels for a while, think I have patches for any such
> warnings that came up on x86, arm and arm64.
> 
> Most of these warnings are false-positive ones, either gcc warning
> about something that is entirely correct, or about something that
> looks suspicious but turns out to be correct after all.
> 
> [...]

Applied to 5.13/scsi-queue, thanks!

[09/11] scsi: lpfc: fix gcc -Wstringop-overread warning
        https://git.kernel.org/mkp/scsi/c/ada48ba70f6b