From: "tip-bot2 for Arvind Sankar" <tip-bot2@linutronix.de>
To: linux-tip-commits@vger.kernel.org
Cc: Arvind Sankar <nivedita@alum.mit.edu>,
Borislav Petkov <bp@suse.de>, Joerg Roedel <jroedel@suse.de>,
x86 <x86@kernel.org>, LKML <linux-kernel@vger.kernel.org>
Subject: [tip: x86/seves] x86/head/64: Disable stack protection for head$(BITS).o
Date: Mon, 19 Oct 2020 19:44:44 -0000 [thread overview]
Message-ID: <160313668451.7002.5512333485207413562.tip-bot2@tip-bot2> (raw)
In-Reply-To: <20201008191623.2881677-6-nivedita@alum.mit.edu>
The following commit has been merged into the x86/seves branch of tip:
Commit-ID: 103a4908ad4da9decdf9bc7216ec5a4861edf703
Gitweb: https://git.kernel.org/tip/103a4908ad4da9decdf9bc7216ec5a4861edf703
Author: Arvind Sankar <nivedita@alum.mit.edu>
AuthorDate: Thu, 08 Oct 2020 15:16:23 -04:00
Committer: Borislav Petkov <bp@suse.de>
CommitterDate: Mon, 19 Oct 2020 13:11:00 +02:00
x86/head/64: Disable stack protection for head$(BITS).o
On 64-bit, the startup_64_setup_env() function added in
866b556efa12 ("x86/head/64: Install startup GDT")
has stack protection enabled because of set_bringup_idt_handler().
This happens when CONFIG_STACKPROTECTOR_STRONG is enabled. It
also currently needs CONFIG_AMD_MEM_ENCRYPT enabled because then
set_bringup_idt_handler() is not an empty stub but that might change in
the future, when the other vendor adds their similar technology.
At this point, %gs is not yet initialized, and this doesn't cause a
crash only because the #PF handler from the decompressor stub is still
installed and handles the page fault.
Disable stack protection for the whole file, and do it on 32-bit as
well to avoid surprises.
[ bp: Extend commit message with the exact explanation how it happens. ]
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Joerg Roedel <jroedel@suse.de>
Link: https://lkml.kernel.org/r/20201008191623.2881677-6-nivedita@alum.mit.edu
---
arch/x86/kernel/Makefile | 2 ++
1 file changed, 2 insertions(+)
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index 04ceea8..68608bd 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -47,6 +47,8 @@ endif
# non-deterministic coverage.
KCOV_INSTRUMENT := n
+CFLAGS_head$(BITS).o += -fno-stack-protector
+
CFLAGS_irq.o := -I $(srctree)/$(src)/../include/asm/trace
obj-y := process_$(BITS).o signal.o
next prev parent reply other threads:[~2020-10-19 19:45 UTC|newest]
Thread overview: 42+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-10-08 19:16 [PATCH v2 0/5] Couple of bugfixes to sev-es series Arvind Sankar
2020-10-08 19:16 ` [PATCH v2 1/5] x86/boot: Initialize boot_params in startup code Arvind Sankar
2020-10-08 19:16 ` [PATCH v2 2/5] x86/boot: Split out command-line related declarations Arvind Sankar
2020-10-08 19:16 ` [PATCH v2 3/5] x86/boot/64: Show original faulting address in case of error Arvind Sankar
2020-10-09 14:42 ` Joerg Roedel
2020-10-08 19:16 ` [PATCH v2 4/5] x86/boot/64: Explicitly map boot_params and command line Arvind Sankar
2020-10-09 14:49 ` Joerg Roedel
2020-10-16 16:27 ` Borislav Petkov
2020-10-16 16:47 ` Arvind Sankar
2020-10-16 17:07 ` Borislav Petkov
2020-10-16 17:20 ` Arvind Sankar
2020-10-16 17:32 ` Borislav Petkov
2020-10-16 20:04 ` [PATCH v3 1/4] " Arvind Sankar
2020-10-16 20:04 ` [PATCH v3 2/4] x86/boot: Initialize boot_params in startup code Arvind Sankar
2020-10-16 20:04 ` [PATCH v3 3/4] x86/boot: Split out command-line related declarations Arvind Sankar
2020-10-16 20:04 ` [PATCH v3 4/4] x86/boot/64: Show original faulting address in case of error Arvind Sankar
2020-10-19 14:51 ` [PATCH v3 1/4] x86/boot/64: Explicitly map boot_params and command line Borislav Petkov
2020-10-19 17:12 ` Arvind Sankar
2020-10-19 17:31 ` Borislav Petkov
2020-10-19 19:44 ` [tip: x86/seves] " tip-bot2 for Arvind Sankar
2020-10-16 21:18 ` [PATCH v2 4/5] " Arvind Sankar
2020-10-16 21:23 ` Borislav Petkov
2020-10-08 19:16 ` [PATCH v2 5/5] x86/head/64: Disable stack protection for head$(BITS).o Arvind Sankar
2020-10-09 14:49 ` Joerg Roedel
2020-10-16 11:17 ` Borislav Petkov
2020-10-16 12:43 ` Arvind Sankar
2020-10-16 13:15 ` Borislav Petkov
2020-10-16 14:16 ` Arvind Sankar
2020-10-19 19:44 ` tip-bot2 for Arvind Sankar [this message]
2020-10-10 19:11 ` [PATCH] x86/boot/64: Initialize 5-level paging variables earlier Arvind Sankar
2020-10-10 19:26 ` Arvind Sankar
2020-10-12 14:08 ` Kirill A. Shutemov
2020-10-12 15:35 ` Arvind Sankar
2020-10-13 8:11 ` Borislav Petkov
2020-10-13 8:20 ` Kirill A. Shutemov
2020-10-13 8:33 ` Borislav Petkov
2020-10-13 9:12 ` Kirill A. Shutemov
2020-10-13 9:46 ` Borislav Petkov
2020-10-15 13:52 ` Kirill A. Shutemov
2020-10-16 10:21 ` Borislav Petkov
2020-10-13 8:59 ` Joerg Roedel
2020-10-19 19:44 ` [tip: x86/seves] " tip-bot2 for Arvind Sankar
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=160313668451.7002.5512333485207413562.tip-bot2@tip-bot2 \
--to=tip-bot2@linutronix.de \
--cc=bp@suse.de \
--cc=jroedel@suse.de \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-tip-commits@vger.kernel.org \
--cc=nivedita@alum.mit.edu \
--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
all inboxes | Powered by JetHome®