devices: ioapic: Increase robustness of IOAPIC operations

Validate the size of I/O reads and check that no request is made to an
out of bounds index (which would cause a panic.)

Signed-off-by: Rob Bradford <robert.bradford@intel.com>
This commit is contained in:
Rob Bradford 2021-09-14 17:06:39 +01:00 committed by Sebastien Boeuf
parent a77160dca4
commit 43f0dd6d25

View File

@ -149,7 +149,10 @@ impl VersionMapped for IoapicState {}
impl BusDevice for Ioapic {
fn read(&mut self, _base: u64, offset: u64, data: &mut [u8]) {
assert!(data.len() == 4);
if data.len() != std::mem::size_of::<u32>() {
warn!("Invalid read size on IOAPIC: {}", data.len());
return;
}
debug!("IOAPIC_R @ offset 0x{:x}", offset);
@ -166,7 +169,10 @@ impl BusDevice for Ioapic {
}
fn write(&mut self, _base: u64, offset: u64, data: &[u8]) -> Option<Arc<Barrier>> {
assert!(data.len() == 4);
if data.len() != std::mem::size_of::<u32>() {
warn!("Invalid write size on IOAPIC: {}", data.len());
return None;
}
debug!("IOAPIC_W @ offset 0x{:x}", offset);
@ -226,6 +232,10 @@ impl Ioapic {
IOAPIC_REG_ID => self.id_reg = (val >> 24) & 0xf,
IOWIN_OFF..=REG_MAX_OFFSET => {
let (index, is_high_bits) = decode_irq_from_selector(self.reg_sel as u8);
if index > NUM_IOAPIC_PINS {
warn!("IOAPIC index out of range: {}", index);
return;
}
if is_high_bits {
self.reg_entries[index] &= 0xffff_ffff;
self.reg_entries[index] |= u64::from(val) << 32;
@ -259,6 +269,10 @@ impl Ioapic {
IOAPIC_REG_ID | IOAPIC_REG_ARBITRATION_ID => (self.id_reg & 0xf) << 24,
IOWIN_OFF..=REG_MAX_OFFSET => {
let (index, is_high_bits) = decode_irq_from_selector(self.reg_sel as u8);
if index > NUM_IOAPIC_PINS {
warn!("IOAPIC index out of range: {}", index);
return 0;
}
if is_high_bits {
(self.reg_entries[index] >> 32) as u32
} else {