On 1/23/21 12:52 PM, Alexander Bulekov wrote:
On 210123 1247, Alexander Bulekov wrote:
Hello,
Here is a reproducer for this bug found by the OSS-Fuzz fuzzer:
cat << EOF | qemu-system-i386 -display none -machine accel=qtest \
-m 512M -machine pc -device floppy,unit=1,id=floppy0,drive=disk0 \
-drive id=disk0,file=null-co://,file.read-zeroes=on,if=none,format=raw \
-qtest stdio
outw 0x3f4 0x2500
outb 0x3f5 0x81
outb 0x3f5 0x0
outb 0x3f5 0x0
outb 0x3f5 0x0
outw 0x3f4 0x0
outw 0x3f4 0x4000
outw 0x3f4 0x13
outb 0x3f5 0x1
outw 0x3f2 0x1405
outw 0x3f4 0x0
EOF
Oops there's a mistake there. Fixed:
cat << EOF | ./qemu-system-i386 -display none -machine accel=qtest \
-m 512M -machine pc -device floppy,unit=1,id=floppy0,drive=disk0 \
-drive id=disk0,file=null-co://,file.read-zeroes=on,if=none,format=raw \
-qtest stdio
outw 0x3f4 0x2500
outb 0x3f5 0x81
outb 0x3f5 0x0
outb 0x3f5 0x0
outb 0x3f5 0x0
outw 0x3f2 0x14
outw 0x3f4 0x0
outw 0x3f4 0x4000
outw 0x3f4 0x13
outb 0x3f5 0x1
outw 0x3f2 0x1405
outw 0x3f4 0x0
EOF
-Alex
This actually still triggers after I apply this patch. It's not the same
bug, or the patch isn't sufficient to address this bug.
--js
