[Xen-changelog] [xen master] arm: crash the guest when it traps on external abort

[patchbot@xxxxxxx]

commit f8c6a9334b251d2e78b0873a71b4d369908fb123
Author:     Wei Chen <Wei.Chen@xxxxxxx>
AuthorDate: Tue Nov 29 15:59:26 2016 +0100
Commit:     Jan Beulich <jbeulich@xxxxxxxx>
CommitDate: Tue Nov 29 15:59:26 2016 +0100

    arm: crash the guest when it traps on external abort
    
    If we spot a data or prefetch abort bearing the ESR_EL2.EA bit set, we
    know that this is an external abort, and that should crash the guest.
    
    This is part of XSA-201.
    
    Signed-off-by: Wei Chen <Wei.Chen@xxxxxxx>
    Reviewed-by: Stefano Stabellini <sstabellini@xxxxxxxxxx>
    Reviewed-by: Steve Capper <steve.capper@xxxxxxx>
    Reviewed-by: Julien Grall <Julien.Grall@xxxxxxx>
---
 xen/arch/arm/traps.c | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/xen/arch/arm/traps.c b/xen/arch/arm/traps.c
index 3bbd002..8ff73fe 100644
--- a/xen/arch/arm/traps.c
+++ b/xen/arch/arm/traps.c
@@ -2409,6 +2409,15 @@ static void do_trap_instr_abort_guest(struct 
cpu_user_regs *regs,
     paddr_t gpa;
     mfn_t mfn;
 
+    /*
+     * If this bit has been set, it means that this instruction abort is caused
+     * by a guest external abort. Currently we crash the guest to protect the
+     * hypervisor. In future one can better handle this by injecting a virtual
+     * abort to the guest.
+     */
+    if ( hsr.iabt.eat )
+        domain_crash_synchronous();
+
     if ( hpfar_is_valid(hsr.iabt.s1ptw, fsc) )
         gpa = get_faulting_ipa(gva);
     else
@@ -2503,6 +2512,15 @@ static void do_trap_data_abort_guest(struct 
cpu_user_regs *regs,
     uint8_t fsc = hsr.dabt.dfsc & ~FSC_LL_MASK;
     mfn_t mfn;
 
+    /*
+     * If this bit has been set, it means that this data abort is caused
+     * by a guest external abort. Currently we crash the guest to protect the
+     * hypervisor. In future one can better handle this by injecting a virtual
+     * abort to the guest.
+     */
+    if ( dabt.eat )
+        domain_crash_synchronous();
+
     info.dabt = dabt;
 #ifdef CONFIG_ARM_32
     info.gva = READ_CP32(HDFAR);
--
generated by git-patchbot for /home/xen/git/xen.git#master

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