From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:54843) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gDbY4-0007zb-FS for qemu-devel@nongnu.org; Fri, 19 Oct 2018 16:39:09 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gDbY3-0002ir-Sg for qemu-devel@nongnu.org; Fri, 19 Oct 2018 16:39:08 -0400 From: Liam Merwick Date: Fri, 19 Oct 2018 21:39:06 +0100 Message-Id: <1539981546-10596-9-git-send-email-Liam.Merwick@oracle.com> In-Reply-To: <1539981546-10596-1-git-send-email-Liam.Merwick@oracle.com> References: <1539981546-10596-1-git-send-email-Liam.Merwick@oracle.com> Subject: [Qemu-devel] [PATCH v4 8/8] kvm: Potential NULL pointer dereference in kvm_arch_init_vcpu() List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: qemu-block@nongnu.org, kwolf@redhat.com, jsnow@redhat.com, berrange@redhat.com, mreitz@redhat.com In kvm_arch_init_vcpu() a call to cpuid_find_entry() can return NULL so the pointer returned should be checked before dereferencing it. Signed-off-by: Liam Merwick --- target/i386/kvm.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/target/i386/kvm.c b/target/i386/kvm.c index dc4047b02fc5..eb19c87a9d25 100644 --- a/target/i386/kvm.c +++ b/target/i386/kvm.c @@ -1177,7 +1177,9 @@ int kvm_arch_init_vcpu(CPUState *cs) c->ecx = c->edx = 0; c = cpuid_find_entry(&cpuid_data.cpuid, kvm_base, 0); - c->eax = MAX(c->eax, KVM_CPUID_SIGNATURE | 0x10); + if (c) { + c->eax = MAX(c->eax, KVM_CPUID_SIGNATURE | 0x10); + } } cpuid_data.cpuid.nent = cpuid_i; -- 1.8.3.1