On Sun, May 13, 2018 at 9:24 AM, Jason A. Donenfeld <ja...@zx2c4.com> wrote: > On Sat, May 12, 2018 at 4:07 AM, Md. Islam <misl...@kent.edu> wrote: >> I'm not an expert on this, but it looks about right. > > Really? Even zeroing between headers_start and headers_end? With the > latest RHEL 7.5 kernel's i40e driver, doing this results in a crash in > kfree. It's possible redhat is putting something silly within > header_start and header_end, and so zeroing it is bad, but I suspect > that instead blanket zeroing it like that might actually be incorrect.
I had similar issue where I was trying to convert an xdp_buff to sk_buff. It was crashing in kfree. I figured it was due to skb_shinfo being empty in my case. skb_skb_shinfo is located at the tail room. http://vger.kernel.org/~davem/skb_data.html > >> look at build_skb() or __build_skb(). It shows the fields that needs to be >> set > > These just kmalloc a new skb, with most fields set to zero. The ones > it modifies are the ones I'm modifying anyway when messing with the > data the skb contains. Doesn't look like there's much to help there. > > > I wrote the original post wondering precisely -- which specifically of > 1-14 are incorrect, and is there anything specific missing from there.
