| 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
| ||
|
Message-Id: <1454030348-17736-30-git-send-email-kamal@canonical.com> Date: Thu, 28 Jan 2016 17:16:07 -0800 From: Kamal Mostafa <kamal@...onical.com> To: linux-kernel@...r.kernel.org, stable@...r.kernel.org, kernel-team@...ts.ubuntu.com Cc: Will Deacon <will.deacon@....com>, Kamal Mostafa <kamal@...onical.com> Subject: [PATCH 3.19.y-ckt 029/210] arm64: mdscr_el1: avoid exposing DCC to userspace 3.19.8-ckt14 -stable review patch. If anyone has any objections, please let me know. ---8<------------------------------------------------------------ From: Will Deacon <will.deacon@....com> commit d8d23fa0f27f3b2942a7bbc7378c7735324ed519 upstream. We don't want to expose the DCC to userspace, particularly as there is a kernel console driver for it. This patch resets mdscr_el1 to disable userspace access to the DCC registers on the cold boot path. Signed-off-by: Will Deacon <will.deacon@....com> Signed-off-by: Kamal Mostafa <kamal@...onical.com> --- arch/arm64/mm/proc.S | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S index 4e778b1..bccdaf5 100644 --- a/arch/arm64/mm/proc.S +++ b/arch/arm64/mm/proc.S @@ -201,7 +201,8 @@ ENTRY(__cpu_setup) mov x0, #3 << 20 msr cpacr_el1, x0 // Enable FP/ASIMD - msr mdscr_el1, xzr // Reset mdscr_el1 + mov x0, #1 << 12 // Reset mdscr_el1 and disable + msr mdscr_el1, x0 // access to the DCC from EL0 /* * Memory region attributes for LPAE: * -- 1.9.1
Powered by blists - more mailing lists