From b10e100d1696782cfebef09b5870dfc6d1b3217b Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Corvin=20K=C3=B6hne?= Date: Fri, 5 May 2023 08:36:20 +0200 Subject: [PATCH] vmm: don't free unallocated memory If vmx or svm is disabled in BIOS or the device isn't supported by vmm, modinit won't allocate these state save areas. As kmem_free panics when passing a NULL pointer to it, loading the vmm kernel module causes a panic too. PR: 271251 Reviewed by: markj Fixes: 74ac712f72cfd6d7b3db3c9d3b72ccf2824aa183 ("vmm: Dynamically allocate a couple of per-CPU state save areas") MFC after: 1 week Sponsored by: Beckhoff Automation GmbH & Co. KG Differential Revision: https://reviews.freebsd.org/D39974 --- sys/amd64/vmm/amd/svm.c | 5 ++++- sys/amd64/vmm/intel/vmx.c | 4 +++- 2 files changed, 7 insertions(+), 2 deletions(-) diff --git a/sys/amd64/vmm/amd/svm.c b/sys/amd64/vmm/amd/svm.c index 0af7342128f2..d295401a9043 100644 --- a/sys/amd64/vmm/amd/svm.c +++ b/sys/amd64/vmm/amd/svm.c @@ -166,7 +166,10 @@ svm_modcleanup(void) { smp_rendezvous(NULL, svm_disable, NULL, NULL); - kmem_free(hsave, (mp_maxid + 1) * PAGE_SIZE); + + if (hsave != NULL) + kmem_free(hsave, (mp_maxid + 1) * PAGE_SIZE); + return (0); } diff --git a/sys/amd64/vmm/intel/vmx.c b/sys/amd64/vmm/intel/vmx.c index 55ed5fdf1a00..8b8f8fe6cb25 100644 --- a/sys/amd64/vmm/intel/vmx.c +++ b/sys/amd64/vmm/intel/vmx.c @@ -619,7 +619,9 @@ vmx_modcleanup(void) nmi_flush_l1d_sw = 0; smp_rendezvous(NULL, vmx_disable, NULL, NULL); - kmem_free(vmxon_region, (mp_maxid + 1) * PAGE_SIZE); + + if (vmxon_region != NULL) + kmem_free(vmxon_region, (mp_maxid + 1) * PAGE_SIZE); return (0); }