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| author | Prasad J Pandit <pjp@fedoraproject.org> | 2020-09-15 23:52:58 +0530 |
|---|---|---|
| committer | Gerd Hoffmann <kraxel@redhat.com> | 2020-09-21 09:44:54 +0200 |
| commit | 1328fe0c32d5474604105b8105310e944976b058 (patch) | |
| tree | 8d26d8476365b01f0022b54db2b386b2869bd6cc /hw/usb | |
| parent | 26d56f489e68386844e33e558c26ecb67256e32d (diff) | |
| download | qemu-1328fe0c32d5474604105b8105310e944976b058.zip qemu-1328fe0c32d5474604105b8105310e944976b058.tar.gz qemu-1328fe0c32d5474604105b8105310e944976b058.tar.bz2 | |
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 <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>
Diffstat (limited to 'hw/usb')
| -rw-r--r-- | hw/usb/hcd-ohci.c | 24 |
1 files changed, 22 insertions, 2 deletions
diff --git a/hw/usb/hcd-ohci.c b/hw/usb/hcd-ohci.c index 1e6e85e..9dc5910 100644 --- a/hw/usb/hcd-ohci.c +++ b/hw/usb/hcd-ohci.c @@ -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) { |