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From: Dan Carpenter <dan.carpenter@oracle.com>
To: Gleb Natapov <gleb@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>, "H. Peter Anvin" <hpa@zytor.com>,
	x86@kernel.org, kvm@vger.kernel.org,
	kernel-janitors@vger.kernel.org
Subject: [patch] kvm: x86: potential shift wrapping bug
Date: Mon, 24 Nov 2014 12:53:00 +0000	[thread overview]
Message-ID: <20141124125300.GA11942@mwanda> (raw)

cs.base is declared as a __u64 variable and vector is a u32 so this
causes a static checker warning.  I'm not very familiar with this code
but my understanding is that the user can set "sipi_vector" to any u32
value in kvm_vcpu_ioctl_x86_set_vcpu_events().

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 34c8f94..6608115 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -7000,7 +7000,7 @@ void kvm_vcpu_deliver_sipi_vector(struct kvm_vcpu *vcpu, unsigned int vector)
 
 	kvm_get_segment(vcpu, &cs, VCPU_SREG_CS);
 	cs.selector = vector << 8;
-	cs.base = vector << 12;
+	cs.base = (u64)vector << 12;
 	kvm_set_segment(vcpu, &cs, VCPU_SREG_CS);
 	kvm_rip_write(vcpu, 0);
 }

WARNING: multiple messages have this Message-ID (diff)
From: Dan Carpenter <dan.carpenter@oracle.com>
To: Gleb Natapov <gleb@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>, "H. Peter Anvin" <hpa@zytor.com>,
	x86@kernel.org, kvm@vger.kernel.org,
	kernel-janitors@vger.kernel.org
Subject: [patch] kvm: x86: potential shift wrapping bug
Date: Mon, 24 Nov 2014 15:53:00 +0300	[thread overview]
Message-ID: <20141124125300.GA11942@mwanda> (raw)

cs.base is declared as a __u64 variable and vector is a u32 so this
causes a static checker warning.  I'm not very familiar with this code
but my understanding is that the user can set "sipi_vector" to any u32
value in kvm_vcpu_ioctl_x86_set_vcpu_events().

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 34c8f94..6608115 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -7000,7 +7000,7 @@ void kvm_vcpu_deliver_sipi_vector(struct kvm_vcpu *vcpu, unsigned int vector)
 
 	kvm_get_segment(vcpu, &cs, VCPU_SREG_CS);
 	cs.selector = vector << 8;
-	cs.base = vector << 12;
+	cs.base = (u64)vector << 12;
 	kvm_set_segment(vcpu, &cs, VCPU_SREG_CS);
 	kvm_rip_write(vcpu, 0);
 }

             reply	other threads:[~2014-11-24 12:53 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-11-24 12:53 Dan Carpenter [this message]
2014-11-24 12:53 ` [patch] kvm: x86: potential shift wrapping bug Dan Carpenter
2014-11-24 13:33 ` Paolo Bonzini
2014-11-24 13:33   ` Paolo Bonzini

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