diff mbox series

[v2,1/5] x86/HVM: correct MMIO emulation cache bounds check

Message ID c7f78078-e0ab-40a7-8624-167512cbe1cf@suse.com (mailing list archive)
State New
Headers show
Series x86/HVM: emulation (MMIO) improvements | expand

Commit Message

Jan Beulich Oct. 1, 2024, 8:48 a.m. UTC 
To avoid overrunning the internal buffer we need to take the offset into
the buffer into account.

Fixes: d95da91fb497 ("x86/HVM: grow MMIO cache data size to 64 bytes")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
---
v2: New.
diff mbox series

Patch

--- a/xen/arch/x86/hvm/emulate.c
+++ b/xen/arch/x86/hvm/emulate.c
@@ -935,7 +935,7 @@  static int hvmemul_phys_mmio_access(
     }
 
     /* Accesses must not overflow the cache's buffer. */
-    if ( size > sizeof(cache->buffer) )
+    if ( offset + size > sizeof(cache->buffer) )
     {
         ASSERT_UNREACHABLE();
         return X86EMUL_UNHANDLEABLE;