Out of bounds in imx_usbphy_read() 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 ```