]> www.infradead.org Git - users/jedix/linux-maple.git/commit
KVM: x86: Fix kernel info-leak in KVM_HC_CLOCK_PAIRING hypercall
authorLiran Alon <liran.alon@oracle.com>
Wed, 7 Nov 2018 22:43:06 +0000 (00:43 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 5 Dec 2018 18:41:23 +0000 (19:41 +0100)
commit08b9a96720a1e67dfed4b22a5192892d556fc5fc
treeadfa4b8f426fffd8f1d8ab4f21d304ac830d9f6f
parent57e972ecad4fdee027a690b64c7d619dae489015
KVM: x86: Fix kernel info-leak in KVM_HC_CLOCK_PAIRING hypercall

commit bcbfbd8ec21096027f1ee13ce6c185e8175166f6 upstream.

kvm_pv_clock_pairing() allocates local var
"struct kvm_clock_pairing clock_pairing" on stack and initializes
all it's fields besides padding (clock_pairing.pad[]).

Because clock_pairing var is written completely (including padding)
to guest memory, failure to init struct padding results in kernel
info-leak.

Fix the issue by making sure to also init the padding with zeroes.

Fixes: 55dd00a73a51 ("KVM: x86: add KVM_HC_CLOCK_PAIRING hypercall")
Reported-by: syzbot+a8ef68d71211ba264f56@syzkaller.appspotmail.com
Reviewed-by: Mark Kanda <mark.kanda@oracle.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arch/x86/kvm/x86.c