Re: [Qemu-block] [QEMU-SECURITY] ide: fix assertion in ide_dma_cb() to prevent qemu DoS from quest

[Alexander Popov]

On 05.07.2019 17:07, Alexander Popov wrote:
> This assertion was introduced in the commit a718978ed58a in July 2015.
> It implies that the size of successful DMA transfers handled in
> ide_dma_cb() should be multiple of 512 (the size of a sector).
> 
> But guest systems can initiate DMA transfers that don't fit this
> requirement. Let's improve the assertion to prevent qemu DoS from quests.

Hello everyone!

This bug was not considered as a security issue by QEMU security team, so I send
this patch to the public mailing list.

Best regards,
Alexander