Merge branch 'misc-BPF-improvements'

Daniel Borkmann says:

====================
This set adds various patches I still had in my queue, first two
are test cases to provide coverage for the recent two fixes that
went to bpf tree, then a small improvement on the error message
for gpl helpers. Next, we expose prog and map id into fdinfo in
order to allow for inspection of these objections currently used
in applications. Patch after that removes a retpoline call for
map lookup/update/delete helpers. A new helper is added in the
subsequent patch to lookup the skb's socket's cgroup v2 id which
can be used in an efficient way for e.g. lookups on egress side.
Next one is a fix to fully clear state info in tunnel/xfrm helpers.
Given this is full cap_sys_admin from init ns and has same priv
requirements like tracing, bpf-next should be okay. A small bug
fix for bpf_asm follows, and next a fix for context access in
tracing which was recently reported. Lastly, a small update in
the maintainer's file to add patchwork url and missing files.

Thanks!

v2 -> v3:
  - Noticed a merge artefact inside uapi header comment, sigh,
    fixed now.
v1 -> v2:
  - minor fix in getting context access work on 32 bit for tracing
  - add paragraph to uapi helper doc to better describe kernel
    build deps for cggroup helper
====================

Signed-off-by: Alexei Starovoitov <ast@kernel.org>

4 files changed, 77 insertions, 30 deletions

diff --git a/kernel/bpf/hashtab.c b/kernel/bpf/hashtab.c
index b76828f23b49a..3ca2198a6d22d 100644
--- a/kernel/bpf/hashtab.c
+++ b/kernel/bpf/hashtab.c
@@ -503,7 +503,9 @@ static u32 htab_map_gen_lookup(struct bpf_map *map, struct bpf_insn *insn_buf)
 	struct bpf_insn *insn = insn_buf;
 	const int ret = BPF_REG_0;
 
-	*insn++ = BPF_EMIT_CALL((u64 (*)(u64, u64, u64, u64, u64))__htab_map_lookup_elem);
+	BUILD_BUG_ON(!__same_type(&__htab_map_lookup_elem,
+		     (void *(*)(struct bpf_map *map, void *key))NULL));
+	*insn++ = BPF_EMIT_CALL(BPF_CAST_CALL(__htab_map_lookup_elem));
 	*insn++ = BPF_JMP_IMM(BPF_JEQ, ret, 0, 1);
 	*insn++ = BPF_ALU64_IMM(BPF_ADD, ret,
 				offsetof(struct htab_elem, key) +
@@ -530,7 +532,9 @@ static u32 htab_lru_map_gen_lookup(struct bpf_map *map,
 	const int ret = BPF_REG_0;
 	const int ref_reg = BPF_REG_1;
 
-	*insn++ = BPF_EMIT_CALL((u64 (*)(u64, u64, u64, u64, u64))__htab_map_lookup_elem);
+	BUILD_BUG_ON(!__same_type(&__htab_map_lookup_elem,
+		     (void *(*)(struct bpf_map *map, void *key))NULL));
+	*insn++ = BPF_EMIT_CALL(BPF_CAST_CALL(__htab_map_lookup_elem));
 	*insn++ = BPF_JMP_IMM(BPF_JEQ, ret, 0, 4);
 	*insn++ = BPF_LDX_MEM(BPF_B, ref_reg, ret,
 			      offsetof(struct htab_elem, lru_node) +
@@ -1369,7 +1373,9 @@ static u32 htab_of_map_gen_lookup(struct bpf_map *map,
 	struct bpf_insn *insn = insn_buf;
 	const int ret = BPF_REG_0;
 
-	*insn++ = BPF_EMIT_CALL((u64 (*)(u64, u64, u64, u64, u64))__htab_map_lookup_elem);
+	BUILD_BUG_ON(!__same_type(&__htab_map_lookup_elem,
+		     (void *(*)(struct bpf_map *map, void *key))NULL));
+	*insn++ = BPF_EMIT_CALL(BPF_CAST_CALL(__htab_map_lookup_elem));
 	*insn++ = BPF_JMP_IMM(BPF_JEQ, ret, 0, 2);
 	*insn++ = BPF_ALU64_IMM(BPF_ADD, ret,
 				offsetof(struct htab_elem, key) +
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 7365d79ae00d0..0fa20624707f2 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -327,13 +327,15 @@ static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp)
 		   "value_size:\t%u\n"
 		   "max_entries:\t%u\n"
 		   "map_flags:\t%#x\n"
-		   "memlock:\t%llu\n",
+		   "memlock:\t%llu\n"
+		   "map_id:\t%u\n",
 		   map->map_type,
 		   map->key_size,
 		   map->value_size,
 		   map->max_entries,
 		   map->map_flags,
-		   map->pages * 1ULL << PAGE_SHIFT);
+		   map->pages * 1ULL << PAGE_SHIFT,
+		   map->id);
 
 	if (owner_prog_type) {
 		seq_printf(m, "owner_prog_type:\t%u\n",
@@ -1070,11 +1072,13 @@ static void bpf_prog_show_fdinfo(struct seq_file *m, struct file *filp)
 		   "prog_type:\t%u\n"
 		   "prog_jited:\t%u\n"
 		   "prog_tag:\t%s\n"
-		   "memlock:\t%llu\n",
+		   "memlock:\t%llu\n"
+		   "prog_id:\t%u\n",
 		   prog->type,
 		   prog->jited,
 		   prog_tag,
-		   prog->pages * 1ULL << PAGE_SHIFT);
+		   prog->pages * 1ULL << PAGE_SHIFT,
+		   prog->aux->id);
 }
 #endif
 
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 1fd9667b29f1a..d6403b5166f49 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -2421,8 +2421,11 @@ record_func_map(struct bpf_verifier_env *env, struct bpf_call_arg_meta *meta,
 	struct bpf_insn_aux_data *aux = &env->insn_aux_data[insn_idx];
 
 	if (func_id != BPF_FUNC_tail_call &&
-	    func_id != BPF_FUNC_map_lookup_elem)
+	    func_id != BPF_FUNC_map_lookup_elem &&
+	    func_id != BPF_FUNC_map_update_elem &&
+	    func_id != BPF_FUNC_map_delete_elem)
 		return 0;
+
 	if (meta->map_ptr == NULL) {
 		verbose(env, "kernel subsystem misconfigured verifier\n");
 		return -EINVAL;
@@ -2462,7 +2465,7 @@ static int check_helper_call(struct bpf_verifier_env *env, int func_id, int insn
 
 	/* eBPF programs must be GPL compatible to use GPL-ed functions */
 	if (!env->prog->gpl_compatible && fn->gpl_only) {
-		verbose(env, "cannot call GPL only function from proprietary program\n");
+		verbose(env, "cannot call GPL-restricted function from non-GPL compatible program\n");
 		return -EINVAL;
 	}
 
@@ -5346,6 +5349,7 @@ static int convert_ctx_accesses(struct bpf_verifier_env *env)
 		 */
 		is_narrower_load = size < ctx_field_size;
 		if (is_narrower_load) {
+			u32 size_default = bpf_ctx_off_adjust_machine(ctx_field_size);
 			u32 off = insn->off;
 			u8 size_code;
 
@@ -5360,7 +5364,7 @@ static int convert_ctx_accesses(struct bpf_verifier_env *env)
 			else if (ctx_field_size == 8)
 				size_code = BPF_DW;
 
-			insn->off = off & ~(ctx_field_size - 1);
+			insn->off = off & ~(size_default - 1);
 			insn->code = BPF_LDX | BPF_MEM | size_code;
 		}
 
@@ -5586,6 +5590,7 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env)
 	struct bpf_insn *insn = prog->insnsi;
 	const struct bpf_func_proto *fn;
 	const int insn_cnt = prog->len;
+	const struct bpf_map_ops *ops;
 	struct bpf_insn_aux_data *aux;
 	struct bpf_insn insn_buf[16];
 	struct bpf_prog *new_prog;
@@ -5715,35 +5720,61 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env)
 		}
 
 		/* BPF_EMIT_CALL() assumptions in some of the map_gen_lookup
-		 * handlers are currently limited to 64 bit only.
+		 * and other inlining handlers are currently limited to 64 bit
+		 * only.
 		 */
 		if (prog->jit_requested && BITS_PER_LONG == 64 &&
-		    insn->imm == BPF_FUNC_map_lookup_elem) {
+		    (insn->imm == BPF_FUNC_map_lookup_elem ||
+		     insn->imm == BPF_FUNC_map_update_elem ||
+		     insn->imm == BPF_FUNC_map_delete_elem)) {
 			aux = &env->insn_aux_data[i + delta];
 			if (bpf_map_ptr_poisoned(aux))
 				goto patch_call_imm;
 
 			map_ptr = BPF_MAP_PTR(aux->map_state);
-			if (!map_ptr->ops->map_gen_lookup)
-				goto patch_call_imm;
+			ops = map_ptr->ops;
+			if (insn->imm == BPF_FUNC_map_lookup_elem &&
+			    ops->map_gen_lookup) {
+				cnt = ops->map_gen_lookup(map_ptr, insn_buf);
+				if (cnt == 0 || cnt >= ARRAY_SIZE(insn_buf)) {
+					verbose(env, "bpf verifier is misconfigured\n");
+					return -EINVAL;
+				}
 
-			cnt = map_ptr->ops->map_gen_lookup(map_ptr, insn_buf);
-			if (cnt == 0 || cnt >= ARRAY_SIZE(insn_buf)) {
-				verbose(env, "bpf verifier is misconfigured\n");
-				return -EINVAL;
-			}
+				new_prog = bpf_patch_insn_data(env, i + delta,
+							       insn_buf, cnt);
+				if (!new_prog)
+					return -ENOMEM;
 
-			new_prog = bpf_patch_insn_data(env, i + delta, insn_buf,
-						       cnt);
-			if (!new_prog)
-				return -ENOMEM;
+				delta    += cnt - 1;
+				env->prog = prog = new_prog;
+				insn      = new_prog->insnsi + i + delta;
+				continue;
+			}
 
-			delta += cnt - 1;
+			BUILD_BUG_ON(!__same_type(ops->map_lookup_elem,
+				     (void *(*)(struct bpf_map *map, void *key))NULL));
+			BUILD_BUG_ON(!__same_type(ops->map_delete_elem,
+				     (int (*)(struct bpf_map *map, void *key))NULL));
+			BUILD_BUG_ON(!__same_type(ops->map_update_elem,
+				     (int (*)(struct bpf_map *map, void *key, void *value,
+					      u64 flags))NULL));
+			switch (insn->imm) {
+			case BPF_FUNC_map_lookup_elem:
+				insn->imm = BPF_CAST_CALL(ops->map_lookup_elem) -
+					    __bpf_call_base;
+				continue;
+			case BPF_FUNC_map_update_elem:
+				insn->imm = BPF_CAST_CALL(ops->map_update_elem) -
+					    __bpf_call_base;
+				continue;
+			case BPF_FUNC_map_delete_elem:
+				insn->imm = BPF_CAST_CALL(ops->map_delete_elem) -
+					    __bpf_call_base;
+				continue;
+			}
 
-			/* keep walking new program and skip insns we just inserted */
-			env->prog = prog = new_prog;
-			insn      = new_prog->insnsi + i + delta;
-			continue;
+			goto patch_call_imm;
 		}
 
 		if (insn->imm == BPF_FUNC_redirect_map) {
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index af1486d9a0ed6..752992ce35131 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -880,8 +880,14 @@ static bool pe_prog_is_valid_access(int off, int size, enum bpf_access_type type
 		return false;
 	if (type != BPF_READ)
 		return false;
-	if (off % size != 0)
-		return false;
+	if (off % size != 0) {
+		if (sizeof(unsigned long) != 4)
+			return false;
+		if (size != 8)
+			return false;
+		if (off % size != 4)
+			return false;
+	}
 
 	switch (off) {
 	case bpf_ctx_range(struct bpf_perf_event_data, sample_period):