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

Martin KaFai Lau says:

====================
pull-request: bpf-next 2025-09-23

We've added 9 non-merge commits during the last 33 day(s) which contain
a total of 10 files changed, 480 insertions(+), 53 deletions(-).

The main changes are:

1) A new bpf_xdp_pull_data kfunc that supports pulling data from
   a frag into the linear area of a xdp_buff, from Amery Hung.

   This includes changes in the xdp_native.bpf.c selftest, which
   Nimrod's future work depends on.

   It is a merge from a stable branch 'xdp_pull_data' which has
   also been merged to bpf-next.

   There is a conflict with recent changes in 'include/net/xdp.h'
   in the net-next tree that will need to be resolved.

2) A compiler warning fix when CONFIG_NET=n in the recent dynptr
   skb_meta support, from Jakub Sitnicki.

* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next:
  selftests: drv-net: Pull data before parsing headers
  selftests/bpf: Test bpf_xdp_pull_data
  bpf: Support specifying linear xdp packet data size for BPF_PROG_TEST_RUN
  bpf: Make variables in bpf_prog_test_run_xdp less confusing
  bpf: Clear packet pointers after changing packet data in kfuncs
  bpf: Support pulling non-linear xdp data
  bpf: Allow bpf_xdp_shrink_data to shrink a frag from head and tail
  bpf: Clear pfmemalloc flag when freeing all fragments
  bpf: Return an error pointer for skb metadata when CONFIG_NET=n
====================

Link: https://patch.msgid.link/20250924050303.2466356-1-martin.lau@linux.dev
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 13 insertions, 0 deletions

diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 27f0bc28ee12..b01cb2c2a4ab 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -12239,6 +12239,7 @@ enum special_kfunc_type {
 	KF_bpf_dynptr_from_skb,
 	KF_bpf_dynptr_from_xdp,
 	KF_bpf_dynptr_from_skb_meta,
+	KF_bpf_xdp_pull_data,
 	KF_bpf_dynptr_slice,
 	KF_bpf_dynptr_slice_rdwr,
 	KF_bpf_dynptr_clone,
@@ -12289,10 +12290,12 @@ BTF_ID(func, bpf_rbtree_right)
 BTF_ID(func, bpf_dynptr_from_skb)
 BTF_ID(func, bpf_dynptr_from_xdp)
 BTF_ID(func, bpf_dynptr_from_skb_meta)
+BTF_ID(func, bpf_xdp_pull_data)
 #else
 BTF_ID_UNUSED
 BTF_ID_UNUSED
 BTF_ID_UNUSED
+BTF_ID_UNUSED
 #endif
 BTF_ID(func, bpf_dynptr_slice)
 BTF_ID(func, bpf_dynptr_slice_rdwr)
@@ -12362,6 +12365,11 @@ static bool is_kfunc_bpf_preempt_enable(struct bpf_kfunc_call_arg_meta *meta)
 	return meta->func_id == special_kfunc_list[KF_bpf_preempt_enable];
 }
 
+static bool is_kfunc_pkt_changing(struct bpf_kfunc_call_arg_meta *meta)
+{
+	return meta->func_id == special_kfunc_list[KF_bpf_xdp_pull_data];
+}
+
 static enum kfunc_ptr_arg_type
 get_kfunc_ptr_arg_type(struct bpf_verifier_env *env,
 		       struct bpf_kfunc_call_arg_meta *meta,
@@ -14081,6 +14089,9 @@ static int check_kfunc_call(struct bpf_verifier_env *env, struct bpf_insn *insn,
 		}
 	}
 
+	if (is_kfunc_pkt_changing(&meta))
+		clear_all_pkt_pointers(env);
+
 	nargs = btf_type_vlen(meta.func_proto);
 	args = (const struct btf_param *)(meta.func_proto + 1);
 	for (i = 0; i < nargs; i++) {
@@ -17798,6 +17809,8 @@ static int visit_insn(int t, struct bpf_verifier_env *env)
 			 */
 			if (ret == 0 && is_kfunc_sleepable(&meta))
 				mark_subprog_might_sleep(env, t);
+			if (ret == 0 && is_kfunc_pkt_changing(&meta))
+				mark_subprog_changes_pkt_data(env, t);
 		}
 		return visit_func_call_insn(t, insns, env, insn->src_reg == BPF_PSEUDO_CALL);