On Mon, Feb 1, 2021 at 5:04 PM Marco Elver <el...@google.com> wrote: > > Avoid the assumption that ksize(kmalloc(S)) == ksize(kmalloc(S)): when > cloning an skb, save and restore truesize after pskb_expand_head(). This > can occur if the allocator decides to service an allocation of the same > size differently (e.g. use a different size class, or pass the > allocation on to KFENCE). > > Because truesize is used for bookkeeping (such as sk_wmem_queued), a > modified truesize of a cloned skb may result in corrupt bookkeeping and > relevant warnings (such as in sk_stream_kill_queues()). > > Link: https://lkml.kernel.org/r/X9JR/j6dmmoy1...@elver.google.com > Reported-by: syzbot+7b99aafdcc2eedea6...@syzkaller.appspotmail.com > Suggested-by: Eric Dumazet <eduma...@google.com> > Signed-off-by: Marco Elver <el...@google.com>
Signed-off-by: Eric Dumazet <eduma...@google.com>
