diff --git a/hw-intc-arm_gic-Fix-interrupt-ID-in-GICD_SGIR-regist.patch b/hw-intc-arm_gic-Fix-interrupt-ID-in-GICD_SGIR-regist.patch new file mode 100644 index 0000000..de999b8 --- /dev/null +++ b/hw-intc-arm_gic-Fix-interrupt-ID-in-GICD_SGIR-regist.patch @@ -0,0 +1,70 @@ +From 3e28567104500238b89ea6b4d684c5350194fea9 Mon Sep 17 00:00:00 2001 +From: =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= +Date: Mon, 21 Jun 2021 10:12:41 +0800 +Subject: [PATCH] hw/intc/arm_gic: Fix interrupt ID in GICD_SGIR register +MIME-Version: 1.0 +Content-Type: text/plain; charset=UTF-8 +Content-Transfer-Encoding: 8bit + +Fix CVE-2021-20221 + +Per the ARM Generic Interrupt Controller Architecture specification +(document "ARM IHI 0048B.b (ID072613)"), the SGIINTID field is 4 bit, +not 10: + + - 4.3 Distributor register descriptions + - 4.3.15 Software Generated Interrupt Register, GICD_SG + + - Table 4-21 GICD_SGIR bit assignments + + The Interrupt ID of the SGI to forward to the specified CPU + interfaces. The value of this field is the Interrupt ID, in + the range 0-15, for example a value of 0b0011 specifies + Interrupt ID 3. + +Correct the irq mask to fix an undefined behavior (which eventually +lead to a heap-buffer-overflow, see [Buglink]): + + $ echo 'writel 0x8000f00 0xff4affb0' | qemu-system-aarch64 -M virt,accel=qtest -qtest stdio + [I 1612088147.116987] OPENED + [R +0.278293] writel 0x8000f00 0xff4affb0 + ../hw/intc/arm_gic.c:1498:13: runtime error: index 944 out of bounds for type 'uint8_t [16][8]' + SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior ../hw/intc/arm_gic.c:1498:13 + +This fixes a security issue when running with KVM on Arm with +kernel-irqchip=off. (The default is kernel-irqchip=on, which is +unaffected, and which is also the correct choice for performance.) + +Cc: qemu-stable@nongnu.org +Fixes: CVE-2021-20221 +Fixes: 9ee6e8bb ("ARMv7 support.") +Buglink: https://bugs.launchpad.net/qemu/+bug/1913916 +Buglink: https://bugs.launchpad.net/qemu/+bug/1913917 + +Reported-by: Alexander Bulekov's avatarAlexander Bulekov +Signed-off-by: Philippe Mathieu-Daudé's avatarPhilippe Mathieu-Daudé +Message-id: 20210131103401.217160-1-f4bug@amsat.org +Reviewed-by: Peter Maydell's avatarPeter Maydell +Signed-off-by: Peter Maydell's avatarPeter Maydell + +Signed-off-by: Jiajie Li +--- + hw/intc/arm_gic.c | 2 +- + 1 file changed, 1 insertion(+), 1 deletion(-) + +diff --git a/hw/intc/arm_gic.c b/hw/intc/arm_gic.c +index 77427a4188..492dabaa1c 100644 +--- a/hw/intc/arm_gic.c ++++ b/hw/intc/arm_gic.c +@@ -1454,7 +1454,7 @@ static void gic_dist_writel(void *opaque, hwaddr offset, + int target_cpu; + + cpu = gic_get_current_cpu(s); +- irq = value & 0x3ff; ++ irq = value & 0xf; + switch ((value >> 24) & 3) { + case 0: + mask = (value >> 16) & ALL_CPU_MASK; +-- +2.27.0 +