diff options
Diffstat (limited to 'system/xen/xsa/xsa212.patch')
-rw-r--r-- | system/xen/xsa/xsa212.patch | 87 |
1 files changed, 0 insertions, 87 deletions
diff --git a/system/xen/xsa/xsa212.patch b/system/xen/xsa/xsa212.patch deleted file mode 100644 index 2c435c413644a..0000000000000 --- a/system/xen/xsa/xsa212.patch +++ /dev/null @@ -1,87 +0,0 @@ -memory: properly check guest memory ranges in XENMEM_exchange handling - -The use of guest_handle_okay() here (as introduced by the XSA-29 fix) -is insufficient here, guest_handle_subrange_okay() needs to be used -instead. - -Note that the uses are okay in -- XENMEM_add_to_physmap_batch handling due to the size field being only - 16 bits wide, -- livepatch_list() due to the limit of 1024 enforced on the - number-of-entries input (leaving aside the fact that this can be - called by a privileged domain only anyway), -- compat mode handling due to counts there being limited to 32 bits, -- everywhere else due to guest arrays being accessed sequentially from - index zero. - -This is XSA-212. - -Reported-by: Jann Horn <jannh@google.com> -Signed-off-by: Jan Beulich <jbeulich@suse.com> -Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com> - ---- a/xen/common/memory.c -+++ b/xen/common/memory.c -@@ -436,8 +436,8 @@ static long memory_exchange(XEN_GUEST_HA - goto fail_early; - } - -- if ( !guest_handle_okay(exch.in.extent_start, exch.in.nr_extents) || -- !guest_handle_okay(exch.out.extent_start, exch.out.nr_extents) ) -+ if ( !guest_handle_subrange_okay(exch.in.extent_start, exch.nr_exchanged, -+ exch.in.nr_extents - 1) ) - { - rc = -EFAULT; - goto fail_early; -@@ -447,11 +447,27 @@ static long memory_exchange(XEN_GUEST_HA - { - in_chunk_order = exch.out.extent_order - exch.in.extent_order; - out_chunk_order = 0; -+ -+ if ( !guest_handle_subrange_okay(exch.out.extent_start, -+ exch.nr_exchanged >> in_chunk_order, -+ exch.out.nr_extents - 1) ) -+ { -+ rc = -EFAULT; -+ goto fail_early; -+ } - } - else - { - in_chunk_order = 0; - out_chunk_order = exch.in.extent_order - exch.out.extent_order; -+ -+ if ( !guest_handle_subrange_okay(exch.out.extent_start, -+ exch.nr_exchanged << out_chunk_order, -+ exch.out.nr_extents - 1) ) -+ { -+ rc = -EFAULT; -+ goto fail_early; -+ } - } - - d = rcu_lock_domain_by_any_id(exch.in.domid); ---- a/xen/include/asm-x86/x86_64/uaccess.h -+++ b/xen/include/asm-x86/x86_64/uaccess.h -@@ -29,8 +29,9 @@ extern void *xlat_malloc(unsigned long * - /* - * Valid if in +ve half of 48-bit address space, or above Xen-reserved area. - * This is also valid for range checks (addr, addr+size). As long as the -- * start address is outside the Xen-reserved area then we will access a -- * non-canonical address (and thus fault) before ever reaching VIRT_START. -+ * start address is outside the Xen-reserved area, sequential accesses -+ * (starting at addr) will hit a non-canonical address (and thus fault) -+ * before ever reaching VIRT_START. - */ - #define __addr_ok(addr) \ - (((unsigned long)(addr) < (1UL<<47)) || \ -@@ -40,7 +41,8 @@ extern void *xlat_malloc(unsigned long * - (__addr_ok(addr) || is_compat_arg_xlat_range(addr, size)) - - #define array_access_ok(addr, count, size) \ -- (access_ok(addr, (count)*(size))) -+ (likely(((count) ?: 0UL) < (~0UL / (size))) && \ -+ access_ok(addr, (count) * (size))) - - #define __compat_addr_ok(d, addr) \ - ((unsigned long)(addr) < HYPERVISOR_COMPAT_VIRT_START(d)) |