Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Daniel Borkmann says:

====================
bpf-next 2022-07-22

We've added 73 non-merge commits during the last 12 day(s) which contain
a total of 88 files changed, 3458 insertions(+), 860 deletions(-).

The main changes are:

1) Implement BPF trampoline for arm64 JIT, from Xu Kuohai.

2) Add ksyscall/kretsyscall section support to libbpf to simplify tracing kernel
   syscalls through kprobe mechanism, from Andrii Nakryiko.

3) Allow for livepatch (KLP) and BPF trampolines to attach to the same kernel
   function, from Song Liu & Jiri Olsa.

4) Add new kfunc infrastructure for netfilter's CT e.g. to insert and change
   entries, from Kumar Kartikeya Dwivedi & Lorenzo Bianconi.

5) Add a ksym BPF iterator to allow for more flexible and efficient interactions
   with kernel symbols, from Alan Maguire.

6) Bug fixes in libbpf e.g. for uprobe binary path resolution, from Dan Carpenter.

7) Fix BPF subprog function names in stack traces, from Alexei Starovoitov.

8) libbpf support for writing custom perf event readers, from Jon Doron.

9) Switch to use SPDX tag for BPF helper man page, from Alejandro Colomar.

10) Fix xsk send-only sockets when in busy poll mode, from Maciej Fijalkowski.

11) Reparent BPF maps and their charging on memcg offlining, from Roman Gushchin.

12) Multiple follow-up fixes around BPF lsm cgroup infra, from Stanislav Fomichev.

13) Use bootstrap version of bpftool where possible to speed up builds, from Pu Lehui.

14) Cleanup BPF verifier's check_func_arg() handling, from Joanne Koong.

15) Make non-prealloced BPF map allocations low priority to play better with
    memcg limits, from Yafang Shao.

16) Fix BPF test runner to reject zero-length data for skbs, from Zhengchao Shao.

17) Various smaller cleanups and improvements all over the place.

* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (73 commits)
  bpf: Simplify bpf_prog_pack_[size|mask]
  bpf: Support bpf_trampoline on functions with IPMODIFY (e.g. livepatch)
  bpf, x64: Allow to use caller address from stack
  ftrace: Allow IPMODIFY and DIRECT ops on the same function
  ftrace: Add modify_ftrace_direct_multi_nolock
  bpf/selftests: Fix couldn't retrieve pinned program in xdp veth test
  bpf: Fix build error in case of !CONFIG_DEBUG_INFO_BTF
  selftests/bpf: Fix test_verifier failed test in unprivileged mode
  selftests/bpf: Add negative tests for new nf_conntrack kfuncs
  selftests/bpf: Add tests for new nf_conntrack kfuncs
  selftests/bpf: Add verifier tests for trusted kfunc args
  net: netfilter: Add kfuncs to set and change CT status
  net: netfilter: Add kfuncs to set and change CT timeout
  net: netfilter: Add kfuncs to allocate and insert CT
  net: netfilter: Deduplicate code in bpf_{xdp,skb}_ct_lookup
  bpf: Add documentation for kfuncs
  bpf: Add support for forcing kfunc args to be trusted
  bpf: Switch to new kfunc flags infrastructure
  tools/resolve_btfids: Add support for 8-byte BTF sets
  bpf: Introduce 8-byte BTF set
  ...
====================

Link: https://lore.kernel.org/r/20220722221218.29943-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 34 insertions, 24 deletions

diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c
index 7e95697a6459..c1f6c1c51d99 100644
--- a/arch/x86/net/bpf_jit_comp.c
+++ b/arch/x86/net/bpf_jit_comp.c
@@ -1950,23 +1950,6 @@ static int invoke_bpf_mod_ret(const struct btf_func_model *m, u8 **pprog,
 	return 0;
 }
 
-static bool is_valid_bpf_tramp_flags(unsigned int flags)
-{
-	if ((flags & BPF_TRAMP_F_RESTORE_REGS) &&
-	    (flags & BPF_TRAMP_F_SKIP_FRAME))
-		return false;
-
-	/*
-	 * BPF_TRAMP_F_RET_FENTRY_RET is only used by bpf_struct_ops,
-	 * and it must be used alone.
-	 */
-	if ((flags & BPF_TRAMP_F_RET_FENTRY_RET) &&
-	    (flags & ~BPF_TRAMP_F_RET_FENTRY_RET))
-		return false;
-
-	return true;
-}
-
 /* Example:
  * __be16 eth_type_trans(struct sk_buff *skb, struct net_device *dev);
  * its 'struct btf_func_model' will be nr_args=2
@@ -2045,9 +2028,6 @@ int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *image, void *i
 	if (nr_args > 6)
 		return -ENOTSUPP;
 
-	if (!is_valid_bpf_tramp_flags(flags))
-		return -EINVAL;
-
 	/* Generated trampoline stack layout:
 	 *
 	 * RBP + 8         [ return address  ]
@@ -2153,10 +2133,15 @@ int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *image, void *i
 	if (flags & BPF_TRAMP_F_CALL_ORIG) {
 		restore_regs(m, &prog, nr_args, regs_off);
 
-		/* call original function */
-		if (emit_call(&prog, orig_call, prog)) {
-			ret = -EINVAL;
-			goto cleanup;
+		if (flags & BPF_TRAMP_F_ORIG_STACK) {
+			emit_ldx(&prog, BPF_DW, BPF_REG_0, BPF_REG_FP, 8);
+			EMIT2(0xff, 0xd0); /* call *rax */
+		} else {
+			/* call original function */
+			if (emit_call(&prog, orig_call, prog)) {
+				ret = -EINVAL;
+				goto cleanup;
+			}
 		}
 		/* remember return value in a stack for bpf prog to access */
 		emit_stx(&prog, BPF_DW, BPF_REG_FP, BPF_REG_0, -8);
@@ -2520,3 +2505,28 @@ bool bpf_jit_supports_subprog_tailcalls(void)
 {
 	return true;
 }
+
+void bpf_jit_free(struct bpf_prog *prog)
+{
+	if (prog->jited) {
+		struct x64_jit_data *jit_data = prog->aux->jit_data;
+		struct bpf_binary_header *hdr;
+
+		/*
+		 * If we fail the final pass of JIT (from jit_subprogs),
+		 * the program may not be finalized yet. Call finalize here
+		 * before freeing it.
+		 */
+		if (jit_data) {
+			bpf_jit_binary_pack_finalize(prog, jit_data->header,
+						     jit_data->rw_header);
+			kvfree(jit_data->addrs);
+			kfree(jit_data);
+		}
+		hdr = bpf_jit_binary_pack_hdr(prog);
+		bpf_jit_binary_pack_free(hdr, NULL);
+		WARN_ON_ONCE(!bpf_prog_kallsyms_verify_off(prog));
+	}
+
+	bpf_prog_unlock_free(prog);
+}