On 200513 1919, P J P wrote: > Hello Alex, > > +-- On Tue, 12 May 2020, Alexander Bulekov wrote --+ > | I noticed this since I found a similar issue recently, using a fuzzer. I > | applied your patches, but I can still reproduce the heap-overflow, unless > | I'm missing something: > > Strange, because with uint16_t type, 'reply_queue_head' should not turn > negative. > > | cat << EOF | qemu-system-i386 -qtest stdio -nographic -monitor none \ > | -serial none -M q35 -device megasas -device scsi-cd,drive=null0 \ > | -blockdev driver=null-co,read-zeroes=on,node-name=null0 -nographic > | outl 0xcf8 0x80001814 > | outl 0xcfc 0xc021 > | outl 0xcf8 0x80001818 > | outl 0xcf8 0x80001804 > | outw 0xcfc 0x7 > | outl 0xcf8 0x80001810 > | outl 0xcfc 0xe10c0000 > | outl 0xcf8 0x8000f810 > | write 0x0 0x18 0x060017e1ff00f8ffffffff60efffffffffffffffffffffff > | write 0xff00 0x1 0x06 > | write 0xc021e10c0040 0x81 > 0x755e08ff0000845e08ff0000935e08ff0000a25e08ff0000b15e08ff0000c05e08ff0000cf5e08ff0000de5e08ff0000ed5e08ff0000fc5e08ff00000b5e08ff00001a5e08ff0000295e08ff0000385e08ff0000475e08ff0000565e08ff0000655e08ff0000745e08ff0000835e08ff0000925e08ff0000a15e08ff0000b05e08 > | -M pc-q35-5.0 -no-shutdown -M q35 -device megasas -device > scsi-cd,drive=null0 -blockdev driver=null-co,read-zeroes=on,node-name=null0 > -nographic > | EOF > > Are qemu options just above EOF right? > > This leads to an assert failure below > > qemu/qtest.c:546:qtest_process_command: assertion failed: (words[1] && > words[2] && words[3]) > ... > Aborted (core dumped) /tmp/im/bin/qemu-system-x86_64 -qtest > stdio -nographic -monitor none -serial none -M q35 -device megasas -device > scsi-cd,drive=null0 -blockdev driver=null-co,read-zeroes=on,node-name=null0 > -nographic < ins
Also, this assertion seems to happen while parsing one of the "write" commands. Maybe the formatting was corrupted in the email. I uploaded the commands here, just in case: wget https://paste.debian.net/plain/1146573 qemu-system-i386 -qtest stdio -nographic -monitor none -serial none \ -M q35 -device megasas -device scsi-cd,drive=null0 \ -blockdev driver=null-co,read-zeroes=on,node-name=null0 \ -nographic < 1146573 -Alex > > Thank you. > -- > Prasad J Pandit / Red Hat Product Security Team > 8685 545E B54C 486B C6EB 271E E285 8B5A F050 DE8D >
