From 22b067020eda76975b442277c93d25565d6e404a Mon Sep 17 00:00:00 2001 From: lijiajie Date: Thu, 27 Aug 2020 20:34:23 +0800 Subject: [PATCH] hw/usb/core.c fix buffer overflow in do_token_setup() function Store calculated setup_len in a local variable, verify it, and only write it to the struct(USBDevice->setup_len)in case it passed the sanity checks. This prevent other code (do_token_{in,out}function specifically) from working with invalid USBDevice->setup_len values and overruning the USBDevice->setup_buf[] buffer. Fixes: CVE-2020-14364 --- hw-usb-core-fix-buffer-overflow.patch | 46 +++++++++++++++++++++++++++ 1 file changed, 46 insertions(+) create mode 100644 hw-usb-core-fix-buffer-overflow.patch diff --git a/hw-usb-core-fix-buffer-overflow.patch b/hw-usb-core-fix-buffer-overflow.patch new file mode 100644 index 0000000..4949557 --- /dev/null +++ b/hw-usb-core-fix-buffer-overflow.patch @@ -0,0 +1,46 @@ +hw-usb-core-fix-buffer-overflow + +From 18ad0451f113ffc3a2ff59c059d189cca1e42842 Mon Sep 17 00:00:00 2001 +From: root +Date: Wed, 19 Aug 2020 17:04:04 +0800 +Subject: [PATCH] hw/usb/core.c fix buffer overflow + +Store calculated setup_len in a local variable, verify it, + and only write it to the struct (USBDevice->setup_len) in case it passed the + sanity checks. + +This prevents other code (do_token_{in,out} function specifically) +from working with invalid USBDevice->setup_len values and overruning +the USBDevice->setup_buf[] buffer. +Store +Fixes: CVE-2020-14364 +Signed-off-by: Gred Hoffman +--- + hw/usb/core.c | 4 ++++ + 1 file changed, 4 insertions(+) + +diff --git a/hw/usb/core.c b/hw/usb/core.c +index 5abd128b..12342f13 100644 +--- a/hw/usb/core.c ++++ b/hw/usb/core.c +@@ -144,6 +144,8 @@ static void do_token_setup(USBDevice *s, USBPacket *p) + "usb_generic_handle_packet: ctrl buffer too small (%d > %zu)\n", + s->setup_len, sizeof(s->data_buf)); + p->status = USB_RET_STALL; ++ s->setup_len = 0; ++ s->setup_state = SETUP_STATE_ACK; + return; + } + +@@ -277,6 +279,8 @@ static void do_parameter(USBDevice *s, USBPacket *p) + "usb_generic_handle_packet: ctrl buffer too small (%d > %zu)\n", + s->setup_len, sizeof(s->data_buf)); + p->status = USB_RET_STALL; ++ s->setup_len = 0; ++ s->setup_state = SETUP_STATE_ACK; + return; + } + +-- +2.23.0 +