linux-kernel - [PATCH 5.8 098/148] s390/runtime_instrumentation: fix storage key handling

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: <20200824082418.734685366@linuxfoundation.org>
Date:   Mon, 24 Aug 2020 10:29:56 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Claudio Imbrenda <imbrenda@...ux.ibm.com>,
        Heiko Carstens <hca@...ux.ibm.com>,
        Sasha Levin <sashal@...nel.org>
Subject: [PATCH 5.8 098/148] s390/runtime_instrumentation: fix storage key handling

From: Heiko Carstens <hca@...ux.ibm.com>

[ Upstream commit 9eaba29c7985236e16468f4e6a49cc18cf01443e ]

The key member of the runtime instrumentation control block contains
only the access key, not the complete storage key. Therefore the value
must be shifted by four bits.
Note: this is only relevant for debugging purposes in case somebody
compiles a kernel with a default storage access key set to a value not
equal to zero.

Fixes: e4b8b3f33fca ("s390: add support for runtime instrumentation")
Reported-by: Claudio Imbrenda <imbrenda@...ux.ibm.com>
Signed-off-by: Heiko Carstens <hca@...ux.ibm.com>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 arch/s390/kernel/runtime_instr.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/s390/kernel/runtime_instr.c b/arch/s390/kernel/runtime_instr.c
index 125c7f6e87150..1788a5454b6fc 100644
--- a/arch/s390/kernel/runtime_instr.c
+++ b/arch/s390/kernel/runtime_instr.c
@@ -57,7 +57,7 @@ static void init_runtime_instr_cb(struct runtime_instr_cb *cb)
 	cb->k = 1;
 	cb->ps = 1;
 	cb->pc = 1;
-	cb->key = PAGE_DEFAULT_KEY;
+	cb->key = PAGE_DEFAULT_KEY >> 4;
 	cb->v = 1;
 }
 
-- 
2.25.1