I/O write make QXL abort in qxl_set_mode()
This bug has been copied automatically from: https://bugs.launchpad.net/qemu/+bug/1880539
Reported by 'Philippe Mathieu-Daudé' on 2020-05-25 :
libFuzzer found: qxl-0: guest bug: qxl_add_memslot: guest_start > guest_end 0xffffffffffffffff > 0x3ffffff qemu-fuzz-i386: hw/display/qxl.c:1611: void qxl_set_mode(PCIQXLDevice *, unsigned int, int): Assertion `qxl_add_memslot(d, 0, devmem, QXL_SYNC) == 0' failed. ==8134== ERROR: libFuzzer: deadly signal #0 0x55fddfcfb3f0 in __sanitizer_print_stack_trace (qemu- fuzz-i386+0xcb13f0) #1 0x55fddfc0a3e1 in fuzzer::PrintStackTrace() (qemu- fuzz-i386+0xbc03e1) #2 0x55fddfbeac6f in fuzzer::Fuzzer::CrashCallback() (qemu- fuzz-i386+0xba0c6f) #3 0x55fddfbeacc3 in fuzzer::Fuzzer::StaticCrashSignalCallback() (qemu-fuzz-i386+0xba0cc3) #4 0x7fd640644c6f (/lib64/libpthread.so.0+0x12c6f) #5 0x7fd640483e34 in __GI_raise (/lib64/libc.so.6+0x37e34) #6 0x7fd64046e894 in __GI_abort (/lib64/libc.so.6+0x22894) #7 0x7fd64046e768 in __assert_fail_base.cold (/lib64/libc.so.6+0x22768) #8 0x7fd64047c565 in __GI___assert_fail (/lib64/libc.so.6+0x30565) #9 0x55fde08afd8b in qxl_set_mode (qemu-fuzz-i386+0x1865d8b) #10 0x55fde08b9602 in ioport_write (qemu-fuzz-i386+0x186f602) #11 0x55fddff170a7 in memory_region_write_accessor (qemu- fuzz-i386+0xecd0a7) #12 0x55fddff16c13 in access_with_adjusted_size (qemu- fuzz-i386+0xeccc13) #13 0x55fddff157b4 in memory_region_dispatch_write (qemu- fuzz-i386+0xecb7b4) Can be reproduce doing "writeb 0x06 0x23" on QXL I/O (PCI BAR #3). Command line: 'qemu-system-i386 -display none -M pc -vga qxl'