linux-scsi.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Arnd Bergmann <arnd@kernel.org>
To: linux-kernel@vger.kernel.org, Martin Sebor <msebor@gcc.gnu.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
	x86@kernel.org
Cc: Arnd Bergmann <arnd@arndb.de>, Ning Sun <ning.sun@intel.com>,
	Jani Nikula <jani.nikula@linux.intel.com>,
	Kalle Valo <kvalo@codeaurora.org>,
	Simon Kelley <simon@thekelleys.org.uk>,
	James Smart <james.smart@broadcom.com>,
	"James E.J. Bottomley" <jejb@linux.ibm.com>,
	Anders Larsen <al@alarsen.net>, Tejun Heo <tj@kernel.org>,
	Serge Hallyn <serge@hallyn.com>, Imre Deak <imre.deak@intel.com>,
	linux-arm-kernel@lists.infradead.org,
	tboot-devel@lists.sourceforge.net,
	intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org,
	ath11k@lists.infradead.org, linux-wireless@vger.kernel.org,
	netdev@vger.kernel.org, linux-scsi@vger.kernel.org,
	cgroups@vger.kernel.org, linux-security-module@vger.kernel.org,
	"H. Peter Anvin" <hpa@zytor.com>,
	Kees Cook <keescook@chromium.org>
Subject: [PATCH 01/11] x86: compressed: avoid gcc-11 -Wstringop-overread warning
Date: Mon, 22 Mar 2021 17:02:39 +0100	[thread overview]
Message-ID: <20210322160253.4032422-2-arnd@kernel.org> (raw)
In-Reply-To: <20210322160253.4032422-1-arnd@kernel.org>

From: Arnd Bergmann <arnd@arndb.de>

gcc gets confused by the comparison of a pointer to an integer listeral,
with the assumption that this is an offset from a NULL pointer and that
dereferencing it is invalid:

In file included from arch/x86/boot/compressed/misc.c:18:
In function ‘parse_elf’,
    inlined from ‘extract_kernel’ at arch/x86/boot/compressed/misc.c:442:2:
arch/x86/boot/compressed/../string.h:15:23: error: ‘__builtin_memcpy’ reading 64 bytes from a region of size 0 [-Werror=stringop-overread]
   15 | #define memcpy(d,s,l) __builtin_memcpy(d,s,l)
      |                       ^~~~~~~~~~~~~~~~~~~~~~~
arch/x86/boot/compressed/misc.c:283:9: note: in expansion of macro ‘memcpy’
  283 |         memcpy(&ehdr, output, sizeof(ehdr));
      |         ^~~~~~

I could not find any good workaround for this, but as this is only
a warning for a failure during early boot, removing the line entirely
works around the warning.

This should probably get addressed in gcc instead, before 11.1 gets
released.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 arch/x86/boot/compressed/misc.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/arch/x86/boot/compressed/misc.c b/arch/x86/boot/compressed/misc.c
index 3a214cc3239f..9ada64e66cb7 100644
--- a/arch/x86/boot/compressed/misc.c
+++ b/arch/x86/boot/compressed/misc.c
@@ -430,8 +430,6 @@ asmlinkage __visible void *extract_kernel(void *rmode, memptr heap,
 		error("Destination address too large");
 #endif
 #ifndef CONFIG_RELOCATABLE
-	if ((unsigned long)output != LOAD_PHYSICAL_ADDR)
-		error("Destination address does not match LOAD_PHYSICAL_ADDR");
 	if (virt_addr != LOAD_PHYSICAL_ADDR)
 		error("Destination virtual address changed when not relocatable");
 #endif
-- 
2.29.2


  reply	other threads:[~2021-03-22 16:03 UTC|newest]

Thread overview: 32+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-03-22 16:02 [PATCH 00/11] treewide: address gcc-11 -Wstringop-overread warnings Arnd Bergmann
2021-03-22 16:02 ` Arnd Bergmann [this message]
2021-03-22 16:02 ` [PATCH 02/11] x86: tboot: avoid Wstringop-overread-warning Arnd Bergmann
2021-03-22 20:29   ` Ingo Molnar
2021-03-22 21:39     ` Arnd Bergmann
2021-03-22 22:07     ` Martin Sebor
2021-03-22 22:49       ` Arnd Bergmann
2021-03-22 23:13       ` Ingo Molnar
2021-03-24  9:11       ` David Laight
2021-03-24 10:39         ` David Laight
2021-03-22 16:02 ` [PATCH 03/11] security: commoncap: fix -Wstringop-overread warning Arnd Bergmann
2021-03-22 16:31   ` Christian Brauner
2021-03-24 20:50   ` James Morris
2021-03-22 16:02 ` [PATCH 04/11] ath11: Wstringop-overread warning Arnd Bergmann
2021-09-28  9:04   ` Kalle Valo
2021-03-22 16:02 ` [PATCH 05/11] qnx: avoid -Wstringop-overread warning Arnd Bergmann
2021-03-22 16:02 ` [PATCH 06/11] cgroup: fix -Wzero-length-bounds warnings Arnd Bergmann
2021-03-30  8:41   ` Michal Koutný
2021-03-30  9:00     ` Arnd Bergmann
2021-03-30 14:44       ` Michal Koutný
2021-03-22 16:02 ` [PATCH 07/11] ARM: sharpsl_param: work around -Wstringop-overread warning Arnd Bergmann
2021-03-22 16:02 ` [PATCH 08/11] atmel: avoid gcc -Wstringop-overflow warning Arnd Bergmann
2021-03-22 16:02 ` [PATCH 09/11] scsi: lpfc: fix gcc -Wstringop-overread warning Arnd Bergmann
2021-03-22 16:02 ` [PATCH 10/11] drm/i915: avoid stringop-overread warning on pri_latency Arnd Bergmann
2021-03-24 15:30   ` Jani Nikula
2021-03-24 17:22     ` Ville Syrjälä
2021-03-22 16:02 ` [PATCH 11/11] [RFC] drm/i915/dp: fix array overflow warning Arnd Bergmann
2021-03-25  8:05   ` Jani Nikula
2021-03-25  9:53     ` Arnd Bergmann
2021-03-25 14:49       ` Martin Sebor
2021-03-30 10:56   ` Hans de Goede
2021-04-06  4:53 ` [PATCH 00/11] treewide: address gcc-11 -Wstringop-overread warnings Martin K. Petersen

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20210322160253.4032422-2-arnd@kernel.org \
    --to=arnd@kernel.org \
    --cc=al@alarsen.net \
    --cc=arnd@arndb.de \
    --cc=ath11k@lists.infradead.org \
    --cc=bp@alien8.de \
    --cc=cgroups@vger.kernel.org \
    --cc=dri-devel@lists.freedesktop.org \
    --cc=hpa@zytor.com \
    --cc=imre.deak@intel.com \
    --cc=intel-gfx@lists.freedesktop.org \
    --cc=james.smart@broadcom.com \
    --cc=jani.nikula@linux.intel.com \
    --cc=jejb@linux.ibm.com \
    --cc=keescook@chromium.org \
    --cc=kvalo@codeaurora.org \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-scsi@vger.kernel.org \
    --cc=linux-security-module@vger.kernel.org \
    --cc=linux-wireless@vger.kernel.org \
    --cc=mingo@redhat.com \
    --cc=msebor@gcc.gnu.org \
    --cc=netdev@vger.kernel.org \
    --cc=ning.sun@intel.com \
    --cc=serge@hallyn.com \
    --cc=simon@thekelleys.org.uk \
    --cc=tboot-devel@lists.sourceforge.net \
    --cc=tglx@linutronix.de \
    --cc=tj@kernel.org \
    --cc=x86@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).