If the GITS_CBASER Size field is 0, which can correspond to a reset value, the userspace fails to set the GITS_CREADR/CWRITER offsets to 0. This failure is not justified.
Let's allow this setting which can also correspond to a reset value. Signed-off-by: Eric Auger <[email protected]> --- need to CC stable --- virt/kvm/arm/vgic/vgic-its.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c index fbbc97b..76bed2d 100644 --- a/virt/kvm/arm/vgic/vgic-its.c +++ b/virt/kvm/arm/vgic/vgic-its.c @@ -1329,7 +1329,7 @@ static void vgic_mmio_write_its_cwriter(struct kvm *kvm, struct vgic_its *its, reg = update_64bit_reg(its->cwriter, addr & 7, len, val); reg = ITS_CMD_OFFSET(reg); - if (reg >= ITS_CMD_BUFFER_SIZE(its->cbaser)) { + if (reg && reg >= ITS_CMD_BUFFER_SIZE(its->cbaser)) { mutex_unlock(&its->cmd_lock); return; } @@ -1370,7 +1370,7 @@ static int vgic_mmio_uaccess_write_its_creadr(struct kvm *kvm, } cmd_offset = ITS_CMD_OFFSET(val); - if (cmd_offset >= ITS_CMD_BUFFER_SIZE(its->cbaser)) { + if (cmd_offset && cmd_offset >= ITS_CMD_BUFFER_SIZE(its->cbaser)) { ret = -EINVAL; goto out; } -- 2.5.5
