linux-kernel - [PATCH v5 12/13] x86/xsaves: Fix fpstate

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]

Date:	Mon,  9 May 2016 13:46:09 -0700
From:	Yu-cheng Yu <yu-cheng.yu@...el.com>
To:	linux-kernel@...r.kernel.org, x86@...nel.org,
	"H. Peter Anvin" <hpa@...or.com>,
	Thomas Gleixner <tglx@...utronix.de>,
	Ingo Molnar <mingo@...hat.com>
Cc:	Dave Hansen <dave.hansen@...ux.intel.com>,
	Andy Lutomirski <luto@...nel.org>,
	Borislav Petkov <bp@...e.de>,
	Sai Praneeth Prakhya <sai.praneeth.prakhya@...el.com>,
	"Ravi V. Shankar" <ravi.v.shankar@...el.com>,
	Fenghua Yu <fenghua.yu@...el.com>,
	Yu-cheng Yu <yu-cheng.yu@...el.com>
Subject: [PATCH v5 12/13] x86/xsaves: Fix fpstate_init() for XSAVES

When XSAVES is used, xsave.header.xcomp_bv[63] must be set.

Signed-off-by: Yu-cheng Yu <yu-cheng.yu@...el.com>
---
 arch/x86/kernel/fpu/core.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c
index 41ab106..25e2605 100644
--- a/arch/x86/kernel/fpu/core.c
+++ b/arch/x86/kernel/fpu/core.c
@@ -224,6 +224,9 @@ void fpstate_init(union fpregs_state *state)
 
 	memset(state, 0, kernel_xstate_size);
 
+	if (cpu_has_xsaves)
+		state->xsave.header.xcomp_bv = (u64)1 << 63;
+
 	if (cpu_has_fxsr)
 		fpstate_init_fxstate(&state->fxsave);
 	else
-- 
1.9.1