git: 1f3bfc60550c - main - bhyve: avoid a potential deadlock

The branch main has been updated by corvink:

URL: https://cgit.FreeBSD.org/src/commit/?id=1f3bfc60550cdd019f00bf6d274db762fda4ed2c

commit 1f3bfc60550cdd019f00bf6d274db762fda4ed2c
Author:     Pierre Pronchery <khorben@defora.org>
AuthorDate: 2024-08-05 07:46:01 +0000
Commit:     Corvin Köhne <corvink@FreeBSD.org>
CommitDate: 2024-08-05 07:48:22 +0000

    bhyve: avoid a potential deadlock
    
    This unlocks a mutex in an error path, that would otherwise remain locked and
    potentially cause a deadlock later on.
    
    Reported by:            Coverity Scan
    CID:                    1521334
    Reviewed by:            corvink, markj
    MFC after:              1 week
    Sponsored by:           The FreeBSD Foundation
    Differential Revision:  https://reviews.freebsd.org/D45401
---
 usr.sbin/bhyve/tpm_intf_crb.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/usr.sbin/bhyve/tpm_intf_crb.c b/usr.sbin/bhyve/tpm_intf_crb.c
index af0214dd1760..0f9a8d1dd53b 100644
--- a/usr.sbin/bhyve/tpm_intf_crb.c
+++ b/usr.sbin/bhyve/tpm_intf_crb.c
@@ -348,8 +348,10 @@ tpm_crb_mem_handler(struct vcpu *vcpu __unused, const int dir,
 			pthread_mutex_lock(&crb->mutex);
 			tpm_crb_mmiocpy(&start, val, size);
 
-			if (!start.start || crb->regs.ctrl_start.start)
+			if (!start.start || crb->regs.ctrl_start.start) {
+				pthread_mutex_unlock(&crb->mutex);
 				break;
+			}
 
 			crb->regs.ctrl_start.start = true;