diff options
Diffstat (limited to 'system/xen/xsa/xsa250.patch')
| -rw-r--r-- | system/xen/xsa/xsa250.patch | 67 |
1 files changed, 0 insertions, 67 deletions
diff --git a/system/xen/xsa/xsa250.patch b/system/xen/xsa/xsa250.patch deleted file mode 100644 index 26aeb33fedaf..000000000000 --- a/system/xen/xsa/xsa250.patch +++ /dev/null @@ -1,67 +0,0 @@ -From: Jan Beulich <jbeulich@suse.com> -Subject: x86/shadow: fix ref-counting error handling - -The old-Linux handling in shadow_set_l4e() mistakenly ORed together the -results of sh_get_ref() and sh_pin(). As the latter failing is not a -correctness problem, simply ignore its return value. - -In sh_set_toplevel_shadow() a failing sh_get_ref() must not be -accompanied by installing the entry, despite the domain being crashed. - -This is XSA-250. - -Signed-off-by: Jan Beulich <jbeulich@suse.com> -Reviewed-by: Tim Deegan <tim@xen.org> - ---- a/xen/arch/x86/mm/shadow/multi.c -+++ b/xen/arch/x86/mm/shadow/multi.c -@@ -923,7 +923,7 @@ static int shadow_set_l4e(struct domain - shadow_l4e_t new_sl4e, - mfn_t sl4mfn) - { -- int flags = 0, ok; -+ int flags = 0; - shadow_l4e_t old_sl4e; - paddr_t paddr; - ASSERT(sl4e != NULL); -@@ -938,15 +938,16 @@ static int shadow_set_l4e(struct domain - { - /* About to install a new reference */ - mfn_t sl3mfn = shadow_l4e_get_mfn(new_sl4e); -- ok = sh_get_ref(d, sl3mfn, paddr); -- /* Are we pinning l3 shadows to handle wierd linux behaviour? */ -- if ( sh_type_is_pinnable(d, SH_type_l3_64_shadow) ) -- ok |= sh_pin(d, sl3mfn); -- if ( !ok ) -+ -+ if ( !sh_get_ref(d, sl3mfn, paddr) ) - { - domain_crash(d); - return SHADOW_SET_ERROR; - } -+ -+ /* Are we pinning l3 shadows to handle weird Linux behaviour? */ -+ if ( sh_type_is_pinnable(d, SH_type_l3_64_shadow) ) -+ sh_pin(d, sl3mfn); - } - - /* Write the new entry */ -@@ -3965,14 +3966,15 @@ sh_set_toplevel_shadow(struct vcpu *v, - - /* Take a ref to this page: it will be released in sh_detach_old_tables() - * or the next call to set_toplevel_shadow() */ -- if ( !sh_get_ref(d, smfn, 0) ) -+ if ( sh_get_ref(d, smfn, 0) ) -+ new_entry = pagetable_from_mfn(smfn); -+ else - { - SHADOW_ERROR("can't install %#lx as toplevel shadow\n", mfn_x(smfn)); - domain_crash(d); -+ new_entry = pagetable_null(); - } - -- new_entry = pagetable_from_mfn(smfn); -- - install_new_entry: - /* Done. Install it */ - SHADOW_PRINTK("%u/%u [%u] gmfn %#"PRI_mfn" smfn %#"PRI_mfn"\n", |