From: Ian Campbell Date: Mon, 30 Mar 2015 11:12:34 +0000 (+0100) Subject: xen: arm: Allow traps from 32 bit userspace on 64 bit hypervisors again X-Git-Tag: archive/raspbian/4.8.0-1+rpi1~1^2~3490 X-Git-Url: https://dgit.raspbian.org/%22http://www.example.com/cgi/%22/%22http:/www.example.com/cgi/%22?a=commitdiff_plain;h=650ed2cef3284bfa6918924bc6a7ac8662ce2807;p=xen.git xen: arm: Allow traps from 32 bit userspace on 64 bit hypervisors again This removes the unconditional #undef injected in response to such traps which was added by the fixes to CVE-2014-5147 / XSA-102 in c0020e099702 "xen: arm: Handle traps from 32-bit userspace on 64-bit kernel as undef", we now handle such traps correctly. Signed-off-by: Ian Campbell Reviewed-by: Julien Grall --- diff --git a/xen/arch/arm/traps.c b/xen/arch/arm/traps.c index cf7a2fd8b4..7af527cd6b 100644 --- a/xen/arch/arm/traps.c +++ b/xen/arch/arm/traps.c @@ -2070,18 +2070,6 @@ asmlinkage void do_trap_hypervisor(struct cpu_user_regs *regs) enter_hypervisor_head(regs); - /* - * We currently do not handle 32-bit userspace on 64-bit kernels - * correctly (See XSA-102). Until that is resolved we treat any - * trap from 32-bit userspace on 64-bit kernel as undefined. - */ - if ( !hyp_mode(regs) && is_64bit_domain(current->domain) && - psr_mode_is_32bit(regs->cpsr) ) - { - inject_undef_exception(regs, hsr.len); - return; - } - switch (hsr.ec) { case HSR_EC_WFI_WFE: if ( !check_conditional_instr(regs, hsr) )