Re: [PATCH] hw/net/vmxnet3: Fix guest-triggerable assert()
17.08.2023 15:56, Thomas Huth wrote: The assert() that checks for valid MTU sizes can be triggered by the guest (e.g. with the reproducer code from the bug ticket https://gitlab.com/qemu-project/qemu/-/issues/517 ). Let's avoid this problem by simply logging the error and refusing to activate the device instead. I'm applying this to trivial-patches tree with some hesitation :) Thanks, /mjt Fixes: d05dcd94ae ("net: vmxnet3: validate configuration values during activate") Signed-off-by: Thomas Huth --- hw/net/vmxnet3.c | 5 - 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/hw/net/vmxnet3.c b/hw/net/vmxnet3.c index 5dfacb1098..6674122a7e 100644 --- a/hw/net/vmxnet3.c +++ b/hw/net/vmxnet3.c @@ -1439,7 +1439,10 @@ static void vmxnet3_activate_device(VMXNET3State *s) vmxnet3_setup_rx_filtering(s); /* Cache fields from shared memory */ s->mtu = VMXNET3_READ_DRV_SHARED32(d, s->drv_shmem, devRead.misc.mtu); -assert(VMXNET3_MIN_MTU <= s->mtu && s->mtu <= VMXNET3_MAX_MTU); +if (s->mtu < VMXNET3_MIN_MTU || s->mtu > VMXNET3_MAX_MTU) { +qemu_log_mask(LOG_GUEST_ERROR, "vmxnet3: Bad MTU size: %d\n", s->mtu); +return; +} VMW_CFPRN("MTU is %u", s->mtu); s->max_rx_frags =
Re: [PATCH] hw/net/vmxnet3: Fix guest-triggerable assert()
Hi Thomas, On 17/8/23 14:56, Thomas Huth wrote: The assert() that checks for valid MTU sizes can be triggered by the guest (e.g. with the reproducer code from the bug ticket https://gitlab.com/qemu-project/qemu/-/issues/517 ). Let's avoid this problem by simply logging the error and refusing to activate the device instead. Fixes: d05dcd94ae ("net: vmxnet3: validate configuration values during activate") Signed-off-by: Thomas Huth --- hw/net/vmxnet3.c | 5 - 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/hw/net/vmxnet3.c b/hw/net/vmxnet3.c index 5dfacb1098..6674122a7e 100644 --- a/hw/net/vmxnet3.c +++ b/hw/net/vmxnet3.c @@ -1439,7 +1439,10 @@ static void vmxnet3_activate_device(VMXNET3State *s) vmxnet3_setup_rx_filtering(s); /* Cache fields from shared memory */ s->mtu = VMXNET3_READ_DRV_SHARED32(d, s->drv_shmem, devRead.misc.mtu); -assert(VMXNET3_MIN_MTU <= s->mtu && s->mtu <= VMXNET3_MAX_MTU); +if (s->mtu < VMXNET3_MIN_MTU || s->mtu > VMXNET3_MAX_MTU) { +qemu_log_mask(LOG_GUEST_ERROR, "vmxnet3: Bad MTU size: %d\n", s->mtu); mtu is uint32_t, otherwise: Reviewed-by: Philippe Mathieu-Daudé +return; +} VMW_CFPRN("MTU is %u", s->mtu); s->max_rx_frags =
[PATCH] hw/net/vmxnet3: Fix guest-triggerable assert()
The assert() that checks for valid MTU sizes can be triggered by the guest (e.g. with the reproducer code from the bug ticket https://gitlab.com/qemu-project/qemu/-/issues/517 ). Let's avoid this problem by simply logging the error and refusing to activate the device instead. Fixes: d05dcd94ae ("net: vmxnet3: validate configuration values during activate") Signed-off-by: Thomas Huth --- hw/net/vmxnet3.c | 5 - 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/hw/net/vmxnet3.c b/hw/net/vmxnet3.c index 5dfacb1098..6674122a7e 100644 --- a/hw/net/vmxnet3.c +++ b/hw/net/vmxnet3.c @@ -1439,7 +1439,10 @@ static void vmxnet3_activate_device(VMXNET3State *s) vmxnet3_setup_rx_filtering(s); /* Cache fields from shared memory */ s->mtu = VMXNET3_READ_DRV_SHARED32(d, s->drv_shmem, devRead.misc.mtu); -assert(VMXNET3_MIN_MTU <= s->mtu && s->mtu <= VMXNET3_MAX_MTU); +if (s->mtu < VMXNET3_MIN_MTU || s->mtu > VMXNET3_MAX_MTU) { +qemu_log_mask(LOG_GUEST_ERROR, "vmxnet3: Bad MTU size: %d\n", s->mtu); +return; +} VMW_CFPRN("MTU is %u", s->mtu); s->max_rx_frags = -- 2.39.3