lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Message-ID: <CAHS8izPW++mf1rq2XdezvXJpxhc6Ey1-_2nbpEymm5KThV18yw@mail.gmail.com> Date: Mon, 6 Nov 2023 16:23:52 -0800 From: Mina Almasry <almasrymina@...gle.com> To: David Ahern <dsahern@...nel.org> Cc: netdev@...r.kernel.org, linux-kernel@...r.kernel.org, linux-arch@...r.kernel.org, linux-kselftest@...r.kernel.org, linux-media@...r.kernel.org, dri-devel@...ts.freedesktop.org, linaro-mm-sig@...ts.linaro.org, "David S. Miller" <davem@...emloft.net>, Eric Dumazet <edumazet@...gle.com>, Jakub Kicinski <kuba@...nel.org>, Paolo Abeni <pabeni@...hat.com>, Jesper Dangaard Brouer <hawk@...nel.org>, Ilias Apalodimas <ilias.apalodimas@...aro.org>, Arnd Bergmann <arnd@...db.de>, Willem de Bruijn <willemdebruijn.kernel@...il.com>, Shuah Khan <shuah@...nel.org>, Sumit Semwal <sumit.semwal@...aro.org>, Christian König <christian.koenig@....com>, Shakeel Butt <shakeelb@...gle.com>, Jeroen de Borst <jeroendb@...gle.com>, Praveen Kaligineedi <pkaligineedi@...gle.com>, Willem de Bruijn <willemb@...gle.com>, Kaiyuan Zhang <kaiyuanz@...gle.com> Subject: Re: [RFC PATCH v3 09/12] net: add support for skbs with unreadable frags On Mon, Nov 6, 2023 at 4:16 PM David Ahern <dsahern@...nel.org> wrote: > > On 11/5/23 7:44 PM, Mina Almasry wrote: > > diff --git a/net/core/datagram.c b/net/core/datagram.c > > index 176eb5834746..cdd4fb129968 100644 > > --- a/net/core/datagram.c > > +++ b/net/core/datagram.c > > @@ -425,6 +425,9 @@ static int __skb_datagram_iter(const struct sk_buff *skb, int offset, > > return 0; > > } > > > > + if (skb_frags_not_readable(skb)) > > + goto short_copy; > > + > > /* Copy paged appendix. Hmm... why does this look so complicated? */ > > for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { > > int end; > > @@ -616,6 +619,9 @@ int __zerocopy_sg_from_iter(struct msghdr *msg, struct sock *sk, > > { > > int frag; > > > > + if (skb_frags_not_readable(skb)) > > + return -EFAULT; > > This check .... > > + > > if (msg && msg->msg_ubuf && msg->sg_from_iter) > > return msg->sg_from_iter(sk, skb, from, length); > > > ... should go here. That allows custome sg_from_iter to have access to > the skb. What matters is not expecting struct page (e.g., refcounting); > if the custom iter does not do that then all is well. io_uring's iter > does not look at the pages, so all good. > > > > > diff --git a/net/core/gro.c b/net/core/gro.c > > index 42d7f6755f32..56046d65386a 100644 > > --- a/net/core/gro.c > > +++ b/net/core/gro.c > > @@ -390,6 +390,9 @@ static void gro_pull_from_frag0(struct sk_buff *skb, int grow) > > { > > struct skb_shared_info *pinfo = skb_shinfo(skb); > > > > + if (WARN_ON_ONCE(skb_frags_not_readable(skb))) > > + return; > > + > > BUG_ON(skb->end - skb->tail < grow); > > > > memcpy(skb_tail_pointer(skb), NAPI_GRO_CB(skb)->frag0, grow); > > @@ -411,7 +414,7 @@ static void gro_try_pull_from_frag0(struct sk_buff *skb) > > { > > int grow = skb_gro_offset(skb) - skb_headlen(skb); > > > > - if (grow > 0) > > + if (grow > 0 && !skb_frags_not_readable(skb)) > > gro_pull_from_frag0(skb, grow); > > } > > > > diff --git a/net/core/skbuff.c b/net/core/skbuff.c > > index 13eca4fd25e1..f01673ed2eff 100644 > > --- a/net/core/skbuff.c > > +++ b/net/core/skbuff.c > > @@ -1230,6 +1230,14 @@ void skb_dump(const char *level, const struct sk_buff *skb, bool full_pkt) > > struct page *p; > > u8 *vaddr; > > > > + if (skb_frag_is_page_pool_iov(frag)) { > > Why skb_frag_is_page_pool_iov here vs skb_frags_not_readable? Seems like a silly choice on my end. I should probably check skb_frags_not_readable() and not kmap any frags in that case. Will do. -- Thanks, Mina
Powered by blists - more mailing lists