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hw: usb: hcd-ohci: check len and frame_number variables

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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 <pgn@zju.edu.cn>
Reported-by: Yongkang Jia <j_kangel@163.com>
Reported-by: Yi Ren <yunye.ry@alibaba-inc.com>
Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org>
Message-id: 20200915182259.68522-2-ppandit@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
This commit is contained in:
Prasad J Pandit 2020-09-15 23:52:58 +05:30 committed by Gerd Hoffmann
parent 26d56f489e
commit 1328fe0c32
1 changed files with 22 additions and 2 deletions
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24
hw/usb/hcd-ohci.c
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@ -731,7 +731,11 @@ 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) &&
@ -764,7 +768,12 @@ 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)) {
@ -773,6 +782,9 @@ 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,
@ -975,8 +987,16 @@ 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) {