diff options
| author | Jan Beulich <jbeulich@suse.com> | 2013-10-14 11:18:20 +0200 |
|---|---|---|
| committer | Jan Beulich <jbeulich@suse.com> | 2013-10-14 11:18:20 +0200 |
| commit | 7b17418d1a09fa386222394c0ba30be3bd179c8a (patch) | |
| tree | b7cc8851b6c139f64a344ee0a5b1ce2a97d1dfa4 | |
| parent | 6ab2551502847834c9c4e581d546ccfcf72a51a6 (diff) | |
| download | xen-7b17418d1a09fa386222394c0ba30be3bd179c8a.tar.gz xen-7b17418d1a09fa386222394c0ba30be3bd179c8a.tar.bz2 xen-7b17418d1a09fa386222394c0ba30be3bd179c8a.zip | |
x86: check for canonical address before doing page walks
... as there doesn't really exists any valid mapping for them.
Particularly in the case of do_page_walk() this also avoids returning
non-NULL for such invalid input.
Suggested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Keir Fraser <keir@xen.org>
master commit: 6fd9b0361e2eb5a7f12bdd5cbf7e42c0d1937d26
master date: 2013-10-11 09:31:16 +0200
| -rw-r--r-- | xen/arch/x86/x86_64/mm.c | 2 | ||||
| -rw-r--r-- | xen/arch/x86/x86_64/traps.c | 2 |
2 files changed, 3 insertions, 1 deletions
diff --git a/xen/arch/x86/x86_64/mm.c b/xen/arch/x86/x86_64/mm.c index d1a1c02855..c491b98d87 100644 --- a/xen/arch/x86/x86_64/mm.c +++ b/xen/arch/x86/x86_64/mm.c @@ -135,7 +135,7 @@ void *do_page_walk(struct vcpu *v, unsigned long addr) l2_pgentry_t l2e, *l2t; l1_pgentry_t l1e, *l1t; - if ( is_hvm_vcpu(v) ) + if ( is_hvm_vcpu(v) || !is_canonical_address(addr) ) return NULL; l4t = map_domain_page(mfn); diff --git a/xen/arch/x86/x86_64/traps.c b/xen/arch/x86/x86_64/traps.c index 1054480145..fe02261d88 100644 --- a/xen/arch/x86/x86_64/traps.c +++ b/xen/arch/x86/x86_64/traps.c @@ -169,6 +169,8 @@ void show_page_walk(unsigned long addr) l1_pgentry_t l1e, *l1t; printk("Pagetable walk from %016lx:\n", addr); + if ( !is_canonical_address(addr) ) + return; l4t = map_domain_page(mfn); l4e = l4t[l4_table_offset(addr)]; |