linux-kernel - [tip: x86/urgent] x86/cpu: Fix __x86_return

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

Message-ID: <169217251853.27769.4820136640557863860.tip-bot2@tip-bot2>
Date:   Wed, 16 Aug 2023 07:55:18 -0000
From:   "tip-bot2 for Peter Zijlstra" <tip-bot2@...utronix.de>
To:     linux-tip-commits@...r.kernel.org
Cc:     "Peter Zijlstra (Intel)" <peterz@...radead.org>,
        "Borislav Petkov (AMD)" <bp@...en8.de>, x86@...nel.org,
        linux-kernel@...r.kernel.org
Subject: [tip: x86/urgent] x86/cpu: Fix __x86_return_thunk symbol type

The following commit has been merged into the x86/urgent branch of tip:

Commit-ID:     77f67119004296a9b2503b377d610e08b08afc2a
Gitweb:        https://git.kernel.org/tip/77f67119004296a9b2503b377d610e08b08afc2a
Author:        Peter Zijlstra <peterz@...radead.org>
AuthorDate:    Mon, 14 Aug 2023 13:44:27 +02:00
Committer:     Borislav Petkov (AMD) <bp@...en8.de>
CommitterDate: Wed, 16 Aug 2023 09:39:16 +02:00

x86/cpu: Fix __x86_return_thunk symbol type

Commit

  fb3bd914b3ec ("x86/srso: Add a Speculative RAS Overflow mitigation")

reimplemented __x86_return_thunk with a mix of SYM_FUNC_START and
SYM_CODE_END, this is not a sane combination.

Since nothing should ever actually 'CALL' this, make it consistently
CODE.

Fixes: fb3bd914b3ec ("x86/srso: Add a Speculative RAS Overflow mitigation")
Signed-off-by: Peter Zijlstra (Intel) <peterz@...radead.org>
Signed-off-by: Borislav Petkov (AMD) <bp@...en8.de>
Link: https://lore.kernel.org/r/20230814121148.571027074@infradead.org
---
 arch/x86/lib/retpoline.S | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/arch/x86/lib/retpoline.S b/arch/x86/lib/retpoline.S
index 8db74d8..9427480 100644
--- a/arch/x86/lib/retpoline.S
+++ b/arch/x86/lib/retpoline.S
@@ -263,7 +263,9 @@ SYM_CODE_END(srso_safe_ret)
 SYM_FUNC_END(srso_untrain_ret)
 __EXPORT_THUNK(srso_untrain_ret)
 
-SYM_FUNC_START(__x86_return_thunk)
+SYM_CODE_START(__x86_return_thunk)
+	UNWIND_HINT_FUNC
+	ANNOTATE_NOENDBR
 	ALTERNATIVE_2 "jmp __ret", "call srso_safe_ret", X86_FEATURE_SRSO, \
 			"call srso_safe_ret_alias", X86_FEATURE_SRSO_ALIAS
 	int3