CVE-2021-47240

In the Linux kernel, the following vulnerability has been resolved:

net: qrtr: fix OOB Read in qrtr_endpoint_post

Syzbot reported slab-out-of-bounds Read in qrtr_endpoint_post. The problem was in wrong _size_ type:

if (len != ALIGN(size, 4) + hdrlen) goto err;

If size from qrtr_hdr is 4294967293 (0xfffffffd), the result of ALIGN(size, 4) will be 0. In case of len == hdrlen and size == 4294967293 in header this check won't fail and

skb_put_data(skb, data + hdrlen, size);

will read out of bound from data, which is hdrlen allocated block.