From 1da457d194134d5424a5e18a03d2243c613237bf Mon Sep 17 00:00:00 2001 From: "Huawei Technologies Co., Ltd" Date: Tue, 15 Sep 2020 23:52:58 +0530 Subject: [PATCH] hw: usb: hcd-ohci: check len and frame_number variables While servicing the OHCI transfer descriptors(TD), OHCI host controller derives variables 'start_addr', 'end_addr', 'len' etc. from values supplied by the host controller driver. Host controller driver may supply values such that using above variables leads to out-of-bounds access issues. Add checks to avoid them. AddressSanitizer: stack-buffer-overflow on address 0x7ffd53af76a0 READ of size 2 at 0x7ffd53af76a0 thread T0 #0 ohci_service_iso_td ../hw/usb/hcd-ohci.c:734 #1 ohci_service_ed_list ../hw/usb/hcd-ohci.c:1180 #2 ohci_process_lists ../hw/usb/hcd-ohci.c:1214 #3 ohci_frame_boundary ../hw/usb/hcd-ohci.c:1257 #4 timerlist_run_timers ../util/qemu-timer.c:572 #5 qemu_clock_run_timers ../util/qemu-timer.c:586 #6 qemu_clock_run_all_timers ../util/qemu-timer.c:672 #7 main_loop_wait ../util/main-loop.c:527 #8 qemu_main_loop ../softmmu/vl.c:1676 #9 main ../softmmu/main.c:50 Reported-by: Gaoning Pan Reported-by: Yongkang Jia Reported-by: Yi Ren Signed-off-by: Prasad J Pandit Message-id: 20200915182259.68522-2-ppandit@redhat.com Signed-off-by: Gerd Hoffmann (cherry-picked from 1328fe0c) Fix CVE-2020-25624 Signed-off-by: Alex Chen --- ...check-len-and-frame_number-variables.patch | 99 +++++++++++++++++++ 1 file changed, 99 insertions(+) create mode 100644 hw-usb-hcd-ohci-check-len-and-frame_number-variables.patch diff --git a/hw-usb-hcd-ohci-check-len-and-frame_number-variables.patch b/hw-usb-hcd-ohci-check-len-and-frame_number-variables.patch new file mode 100644 index 0000000..0133d70 --- /dev/null +++ b/hw-usb-hcd-ohci-check-len-and-frame_number-variables.patch @@ -0,0 +1,99 @@ +From 789723b95045b6e44d1d1aef56a8bcb255a10476 Mon Sep 17 00:00:00 2001 +From: Prasad J Pandit +Date: Tue, 15 Sep 2020 23:52:58 +0530 +Subject: [PATCH] hw: usb: hcd-ohci: check len and frame_number variables + +While servicing the OHCI transfer descriptors(TD), OHCI host +controller derives variables 'start_addr', 'end_addr', 'len' +etc. from values supplied by the host controller driver. +Host controller driver may supply values such that using +above variables leads to out-of-bounds access issues. +Add checks to avoid them. + +AddressSanitizer: stack-buffer-overflow on address 0x7ffd53af76a0 + READ of size 2 at 0x7ffd53af76a0 thread T0 + #0 ohci_service_iso_td ../hw/usb/hcd-ohci.c:734 + #1 ohci_service_ed_list ../hw/usb/hcd-ohci.c:1180 + #2 ohci_process_lists ../hw/usb/hcd-ohci.c:1214 + #3 ohci_frame_boundary ../hw/usb/hcd-ohci.c:1257 + #4 timerlist_run_timers ../util/qemu-timer.c:572 + #5 qemu_clock_run_timers ../util/qemu-timer.c:586 + #6 qemu_clock_run_all_timers ../util/qemu-timer.c:672 + #7 main_loop_wait ../util/main-loop.c:527 + #8 qemu_main_loop ../softmmu/vl.c:1676 + #9 main ../softmmu/main.c:50 + +Reported-by: Gaoning Pan +Reported-by: Yongkang Jia +Reported-by: Yi Ren +Signed-off-by: Prasad J Pandit +Message-id: 20200915182259.68522-2-ppandit@redhat.com +Signed-off-by: Gerd Hoffmann +(cherry-picked from 1328fe0c) +Fix CVE-2020-25624 +Signed-off-by: Alex Chen +--- + hw/usb/hcd-ohci.c | 24 ++++++++++++++++++++++-- + 1 file changed, 22 insertions(+), 2 deletions(-) + +diff --git a/hw/usb/hcd-ohci.c b/hw/usb/hcd-ohci.c +index ffe52a09d7..d2dd8efd58 100644 +--- a/hw/usb/hcd-ohci.c ++++ b/hw/usb/hcd-ohci.c +@@ -733,7 +733,11 @@ static int ohci_service_iso_td(OHCIState *ohci, struct ohci_ed *ed, + } + + start_offset = iso_td.offset[relative_frame_number]; +- next_offset = iso_td.offset[relative_frame_number + 1]; ++ if (relative_frame_number < frame_count) { ++ next_offset = iso_td.offset[relative_frame_number + 1]; ++ } else { ++ next_offset = iso_td.be; ++ } + + if (!(OHCI_BM(start_offset, TD_PSW_CC) & 0xe) || + ((relative_frame_number < frame_count) && +@@ -766,7 +770,12 @@ static int ohci_service_iso_td(OHCIState *ohci, struct ohci_ed *ed, + } + } else { + /* Last packet in the ISO TD */ +- end_addr = iso_td.be; ++ end_addr = next_offset; ++ } ++ ++ if (start_addr > end_addr) { ++ trace_usb_ohci_iso_td_bad_cc_overrun(start_addr, end_addr); ++ return 1; + } + + if ((start_addr & OHCI_PAGE_MASK) != (end_addr & OHCI_PAGE_MASK)) { +@@ -775,6 +784,9 @@ static int ohci_service_iso_td(OHCIState *ohci, struct ohci_ed *ed, + } else { + len = end_addr - start_addr + 1; + } ++ if (len > sizeof(ohci->usb_buf)) { ++ len = sizeof(ohci->usb_buf); ++ } + + if (len && dir != OHCI_TD_DIR_IN) { + if (ohci_copy_iso_td(ohci, start_addr, end_addr, ohci->usb_buf, len, +@@ -977,8 +989,16 @@ static int ohci_service_td(OHCIState *ohci, struct ohci_ed *ed) + if ((td.cbp & 0xfffff000) != (td.be & 0xfffff000)) { + len = (td.be & 0xfff) + 0x1001 - (td.cbp & 0xfff); + } else { ++ if (td.cbp > td.be) { ++ trace_usb_ohci_iso_td_bad_cc_overrun(td.cbp, td.be); ++ ohci_die(ohci); ++ return 1; ++ } + len = (td.be - td.cbp) + 1; + } ++ if (len > sizeof(ohci->usb_buf)) { ++ len = sizeof(ohci->usb_buf); ++ } + + pktlen = len; + if (len && dir != OHCI_TD_DIR_IN) { +-- +2.27.0 +