Out of bounds in imx_usbphy_read()

Host environment

• Operating system: Ubuntu 20.04
• OS/kernel version: 5.15.0-56-generic
• Architecture: x86
• QEMU flavor: qemu-system-arm
• QEMU version: 7.2.50
• QEMU command line:

  export QEMU=/path/to/qemu-system-arm
  
  cat << EOF | $QEMU \
  -machine sabrelite -monitor none -serial none \
  -display none -nodefaults -qtest stdio
  readl 0x20c9870
  EOF

Description of problem

The size of the memory region of imx-usb-phy is 0x1000.

memory_region_init_io(&s->iomem, OBJECT(s), &imx_usbphy_ops, s,
                          "imx-usbphy", 0x1000);

A read to s->usbphy[33] will easily overflow.

static uint64_t imx_usbphy_read(void *opaque, hwaddr offset, unsigned size)
{
    // ...
    default:
        value = s->usbphy[index];
        break;
    }

Maybe we should drop this read in default branch.

Steps to reproduce

export QEMU=/path/to/qemu-system-arm

cat << EOF | $QEMU \
-machine sabrelite -monitor none -serial none \
-display none -nodefaults -qtest stdio
readl 0x20c9870
EOF

Additional information

+ DEFAULT_INPUT_MAXSIZE=10000000
+ ./qemu-videzzo-arm-target-videzzo-fuzz-imx-usb-phy -max_len=10000000 -detect_leaks=0 ./crash-2f5e9c8ec69dd69f8db69aaa84dde878482b8690.minimized
==14370==WARNING: ASan doesn't fully support makecontext/swapcontext functions and may produce false positives in some cases!
INFO: found LLVMFuzzerCustomMutator (0x561837db1240). Disabling -len_control by default.
INFO: Running with entropic power schedule (0xFF, 100).
INFO: Seed: 1679742864
INFO: Loaded 1 modules   (583356 inline 8-bit counters): 583356 [0x56183b151000, 0x56183b1df6bc),
INFO: Loaded 1 PC tables (583356 PCs): 583356 [0x56183a86a3b0,0x56183b150f70),
./qemu-videzzo-arm-target-videzzo-fuzz-imx-usb-phy: Running 1 inputs 1 time(s) each.
INFO: Reading pre_seed_input if any ...
INFO: Executing pre_seed_input if any ...
Matching objects by name , *imx-usbphy*
This process will fuzz the following MemoryRegions:
  * imx-usbphy[0] (size 1000)
  * imx-usbphy[0] (size 1000)
This process will fuzz through the following interfaces:
  * clock_step, EVENT_TYPE_CLOCK_STEP, 0xffffffff +0xffffffff, 255,255
  * imx-usbphy, EVENT_TYPE_MMIO_READ, 0x20c9000 +0x1000, 4,4
  * imx-usbphy, EVENT_TYPE_MMIO_WRITE, 0x20c9000 +0x1000, 4,4
  * imx-usbphy, EVENT_TYPE_MMIO_READ, 0x20ca000 +0x1000, 4,4
  * imx-usbphy, EVENT_TYPE_MMIO_WRITE, 0x20ca000 +0x1000, 4,4
INFO: A corpus is not provided, starting from an empty corpus
#2      INITED cov: 3 ft: 4 corp: 1/1b exec/s: 0 rss: 222Mb
Running: ./crash-2f5e9c8ec69dd69f8db69aaa84dde878482b8690.minimized
../hw/usb/imx-usb-phy.c:93:17: runtime error: index 540 out of bounds for type 'uint32_t [33]'
    #0 0x5618357ddb2a in imx_usbphy_read /root/videzzo/videzzo_qemu/qemu/out-san/../hw/usb/imx-usb-phy.c:93:17
    #1 0x561836f07a0b in memory_region_read_accessor /root/videzzo/videzzo_qemu/qemu/out-san/../softmmu/memory.c:441:11
    #2 0x561836ec6501 in access_with_adjusted_size /root/videzzo/videzzo_qemu/qemu/out-san/../softmmu/memory.c:555:18
    #3 0x561836ec38cc in memory_region_dispatch_read1 /root/videzzo/videzzo_qemu/qemu/out-san/../softmmu/memory.c:1425:16
    #4 0x561836ec3008 in memory_region_dispatch_read /root/videzzo/videzzo_qemu/qemu/out-san/../softmmu/memory.c:1458:9
    #5 0x561836f415ad in flatview_read_continue /root/videzzo/videzzo_qemu/qemu/out-san/../softmmu/physmem.c:2892:23
    #6 0x561836f42bb8 in flatview_read /root/videzzo/videzzo_qemu/qemu/out-san/../softmmu/physmem.c:2934:12
    #7 0x561836f42678 in address_space_read_full /root/videzzo/videzzo_qemu/qemu/out-san/../softmmu/physmem.c:2947:18
    #8 0x5618337f4b41 in address_space_read /root/videzzo/videzzo_qemu/qemu/include/exec/memory.h:2873:18
    #9 0x5618337f4b41 in qemu_readl /root/videzzo/videzzo_qemu/qemu/out-san/../tests/qtest/videzzo/videzzo_qemu.c:1037:5
    #10 0x5618337f2c06 in dispatch_mmio_read /root/videzzo/videzzo_qemu/qemu/out-san/../tests/qtest/videzzo/videzzo_qemu.c:1051:35
    #11 0x561837dac6bf in videzzo_dispatch_event /root/videzzo/videzzo.c:1140:5
    #12 0x561837da3a3d in __videzzo_execute_one_input /root/videzzo/videzzo.c:288:9
    #13 0x561837da37e4 in videzzo_execute_one_input /root/videzzo/videzzo.c:329:9
    #14 0x56183380a07c in videzzo_qemu /root/videzzo/videzzo_qemu/qemu/out-san/../tests/qtest/videzzo/videzzo_qemu.c:1520:12
    #15 0x561837db150b in LLVMFuzzerTestOneInput /root/videzzo/videzzo.c:1910:18
    #16 0x5618336ea806 in fuzzer::Fuzzer::ExecuteCallback(unsigned char*, unsigned long) /root/llvm-project/compiler-rt/lib/fuzzer/FuzzerLoop.cpp:594:17
    #17 0x5618336cd434 in fuzzer::RunOneTest(fuzzer::Fuzzer*, char const*, unsigned long) /root/llvm-project/compiler-rt/lib/fuzzer/FuzzerDriver.cpp:323:21
    #18 0x5618336d83de in fuzzer::FuzzerDriver(int*, char***, int (*)(unsigned char*, unsigned long)) /root/llvm-project/compiler-rt/lib/fuzzer/FuzzerDriver.cpp:885:19
    #19 0x5618336c49c6 in main /root/llvm-project/compiler-rt/lib/fuzzer/FuzzerMain.cpp:20:30
    #20 0x7f74d2914082 in __libc_start_main /build/glibc-SzIz7B/glibc-2.31/csu/../csu/libc-start.c:308:16
    #21 0x5618336c4a1d in _start (/root/bugs/metadata/imx_usb_phy-00/qemu-videzzo-arm-target-videzzo-fuzz-imx-usb-phy+0x31cea1d)

SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior ../hw/usb/imx-usb-phy.c:93:17 in
MS: 0 ; base unit: 0000000000000000000000000000000000000000
0x0,0x8,0x70,0x98,0xc,0x2,0x0,0x0,0x0,0x0,0x4,0x0,0x0,0x0,
\x00\x08p\x98\x0c\x02\x00\x00\x00\x00\x04\x00\x00\x00