x86/hvm: Fix Misra Rule 19.1 regression

Despite noticing an impending Rule 19.1 violation, the adjustment made (the
uint32_t cast) wasn't sufficient to avoid it.  Try again.

Subsequently noticed by Coverity too.

Fixes: 6a98383b0877 ("x86/HVM: clear upper halves of GPRs upon entry from 32-bit code")
Coverity-IDs: 1596289 thru 1596298
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
master commit: d0a718a45f14b86471d8eb3083acd72760963470
master date: 2024-04-11 13:23:08 +0100

diff --git a/xen/arch/x86/include/asm/hvm/hvm.h b/xen/arch/x86/include/asm/hvm/hvm.h
index d67565dcb90dc6ac3c8391cdc13628be3f994d3e..e16f9f348961b17439edb283956e557884677bab 100644 (file)
--- a/xen/arch/x86/include/asm/hvm/hvm.h
+++ b/xen/arch/x86/include/asm/hvm/hvm.h
@@ -589,16 +589,16 @@ static inline void hvm_sanitize_regs_fields(struct cpu_user_regs *regs,
     if ( compat )
     {
         /* Clear GPR upper halves, to counteract guests playing games. */
-        regs->rbp = (uint32_t)regs->ebp;
-        regs->rbx = (uint32_t)regs->ebx;
-        regs->rax = (uint32_t)regs->eax;
-        regs->rcx = (uint32_t)regs->ecx;
-        regs->rdx = (uint32_t)regs->edx;
-        regs->rsi = (uint32_t)regs->esi;
-        regs->rdi = (uint32_t)regs->edi;
-        regs->rip = (uint32_t)regs->eip;
-        regs->rflags = (uint32_t)regs->eflags;
-        regs->rsp = (uint32_t)regs->esp;
+        regs->rbp = (uint32_t)regs->rbp;
+        regs->rbx = (uint32_t)regs->rbx;
+        regs->rax = (uint32_t)regs->rax;
+        regs->rcx = (uint32_t)regs->rcx;
+        regs->rdx = (uint32_t)regs->rdx;
+        regs->rsi = (uint32_t)regs->rsi;
+        regs->rdi = (uint32_t)regs->rdi;
+        regs->rip = (uint32_t)regs->rip;
+        regs->rflags = (uint32_t)regs->rflags;
+        regs->rsp = (uint32_t)regs->rsp;
     }
 
 #ifndef NDEBUG