Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf

Daniel Borkmann says:

====================
pull-request: bpf 2024-01-25

The following pull-request contains BPF updates for your *net* tree.

We've added 12 non-merge commits during the last 2 day(s) which contain
a total of 13 files changed, 190 insertions(+), 91 deletions(-).

The main changes are:

1) Fix bpf_xdp_adjust_tail() in context of XSK zero-copy drivers which
   support XDP multi-buffer. The former triggered a NULL pointer
   dereference upon shrinking, from Maciej Fijalkowski & Tirthendu Sarkar.

2) Fix a bug in riscv64 BPF JIT which emitted a wrong prologue and
   epilogue for struct_ops programs, from Pu Lehui.

* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
  i40e: update xdp_rxq_info::frag_size for ZC enabled Rx queue
  i40e: set xdp_rxq_info::frag_size
  xdp: reflect tail increase for MEM_TYPE_XSK_BUFF_POOL
  ice: update xdp_rxq_info::frag_size for ZC enabled Rx queue
  intel: xsk: initialize skb_frag_t::bv_offset in ZC drivers
  ice: remove redundant xdp_rxq_info registration
  i40e: handle multi-buffer packets that are shrunk by xdp prog
  ice: work on pre-XDP prog frag count
  xsk: fix usage of multi-buffer BPF helpers for ZC XDP
  xsk: make xsk_buff_pool responsible for clearing xdp_buff::flags
  xsk: recycle buffer in case Rx queue was full
  riscv, bpf: Fix unpredictable kernel crash about RV64 struct_ops
====================

Link: https://lore.kernel.org/r/20240125084416.10876-1-daniel@iogearbox.net
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

1 files changed, 27 insertions, 0 deletions

diff --git a/include/net/xdp_sock_drv.h b/include/net/xdp_sock_drv.h
index 526c1e7f505e..c9aec9ab6191 100644
--- a/include/net/xdp_sock_drv.h
+++ b/include/net/xdp_sock_drv.h
@@ -159,11 +159,29 @@ static inline struct xdp_buff *xsk_buff_get_frag(struct xdp_buff *first)
 	return ret;
 }
 
+static inline void xsk_buff_del_tail(struct xdp_buff *tail)
+{
+	struct xdp_buff_xsk *xskb = container_of(tail, struct xdp_buff_xsk, xdp);
+
+	list_del(&xskb->xskb_list_node);
+}
+
+static inline struct xdp_buff *xsk_buff_get_tail(struct xdp_buff *first)
+{
+	struct xdp_buff_xsk *xskb = container_of(first, struct xdp_buff_xsk, xdp);
+	struct xdp_buff_xsk *frag;
+
+	frag = list_last_entry(&xskb->pool->xskb_list, struct xdp_buff_xsk,
+			       xskb_list_node);
+	return &frag->xdp;
+}
+
 static inline void xsk_buff_set_size(struct xdp_buff *xdp, u32 size)
 {
 	xdp->data = xdp->data_hard_start + XDP_PACKET_HEADROOM;
 	xdp->data_meta = xdp->data;
 	xdp->data_end = xdp->data + size;
+	xdp->flags = 0;
 }
 
 static inline dma_addr_t xsk_buff_raw_get_dma(struct xsk_buff_pool *pool,
@@ -350,6 +368,15 @@ static inline struct xdp_buff *xsk_buff_get_frag(struct xdp_buff *first)
 	return NULL;
 }
 
+static inline void xsk_buff_del_tail(struct xdp_buff *tail)
+{
+}
+
+static inline struct xdp_buff *xsk_buff_get_tail(struct xdp_buff *first)
+{
+	return NULL;
+}
+
 static inline void xsk_buff_set_size(struct xdp_buff *xdp, u32 size)
 {
 }