git: 32e077f273d9 - stable/13 - bhyve: initialize register value

From: Ed Maste <emaste_at_FreeBSD.org>
Date: Mon, 30 Sep 2024 12:11:54 UTC
The branch stable/13 has been updated by emaste:

URL: https://cgit.FreeBSD.org/src/commit/?id=32e077f273d90c377faaddc5333758940cc52cef

commit 32e077f273d90c377faaddc5333758940cc52cef
Author:     Pierre Pronchery <pierre@freebsdfoundation.org>
AuthorDate: 2024-07-24 19:33:26 +0000
Commit:     Ed Maste <emaste@FreeBSD.org>
CommitDate: 2024-09-30 12:11:47 +0000

    bhyve: initialize register value
    
    In case of an error in a code pattern like
    
    ```
    uint64_t val;
    error = memread(vcpu, gpa, &val, 1, arg);
    error = vie_update_register(vcpu, reg, val, size);
    ```
    
    uninitialized stack data would be used.
    
    Reported by:    Synacktiv
    Reviewed by:    markj
    Security:       HYP-21
    Sponsored by:   The Alpha-Omega Project
    Sponsored by:   The FreeBSD Foundation
    Differential Revision:  https://reviews.freebsd.org/D46107
    
    (cherry picked from commit 94693ec7c85363f9b0098247489cea3efdb183f9)
    (cherry picked from commit a03acfa43410b3a449fa8d5b1dbba20e0bf02d5a)
---
 sys/amd64/vmm/vmm_ioport.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sys/amd64/vmm/vmm_ioport.c b/sys/amd64/vmm/vmm_ioport.c
index ec270df80c3e..3caea7deac16 100644
--- a/sys/amd64/vmm/vmm_ioport.c
+++ b/sys/amd64/vmm/vmm_ioport.c
@@ -101,7 +101,7 @@ static int
 emulate_inout_port(struct vcpu *vcpu, struct vm_exit *vmexit, bool *retu)
 {
 	ioport_handler_func_t handler;
-	uint32_t mask, val;
+	uint32_t mask, val = 0;
 	int error;
 
 	/*