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
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <20190129113206.834072615@linuxfoundation.org>
Date:   Tue, 29 Jan 2019 12:36:05 +0100
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Daniel Borkmann <daniel@...earbox.net>,
        Alexei Starovoitov <ast@...nel.org>,
        Sasha Levin <sashal@...nel.org>
Subject: [PATCH 4.19 088/103] bpf: move {prev_,}insn_idx into verifier env

4.19-stable review patch.  If anyone has any objections, please let me know.

------------------

[ commit c08435ec7f2bc8f4109401f696fd55159b4b40cb upstream ]

Move prev_insn_idx and insn_idx from the do_check() function into
the verifier environment, so they can be read inside the various
helper functions for handling the instructions. It's easier to put
this into the environment rather than changing all call-sites only
to pass it along. insn_idx is useful in particular since this later
on allows to hold state in env->insn_aux_data[env->insn_idx].

Signed-off-by: Daniel Borkmann <daniel@...earbox.net>
Acked-by: Alexei Starovoitov <ast@...nel.org>
Signed-off-by: Alexei Starovoitov <ast@...nel.org>
Signed-off-by: Daniel Borkmann <daniel@...earbox.net>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 include/linux/bpf_verifier.h |  2 +
 kernel/bpf/verifier.c        | 75 ++++++++++++++++++------------------
 2 files changed, 40 insertions(+), 37 deletions(-)

diff --git a/include/linux/bpf_verifier.h b/include/linux/bpf_verifier.h
index 1fd6fa822d2c..b1587ffdea7b 100644
--- a/include/linux/bpf_verifier.h
+++ b/include/linux/bpf_verifier.h
@@ -186,6 +186,8 @@ struct bpf_subprog_info {
  * one verifier_env per bpf_check() call
  */
 struct bpf_verifier_env {
+	u32 insn_idx;
+	u32 prev_insn_idx;
 	struct bpf_prog *prog;		/* eBPF program being verified */
 	const struct bpf_verifier_ops *ops;
 	struct bpf_verifier_stack_elem *head; /* stack of verifier states to be processed */
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 2bbb98535b70..6d11320998c6 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -4816,7 +4816,6 @@ static int do_check(struct bpf_verifier_env *env)
 	struct bpf_insn *insns = env->prog->insnsi;
 	struct bpf_reg_state *regs;
 	int insn_cnt = env->prog->len, i;
-	int insn_idx, prev_insn_idx = 0;
 	int insn_processed = 0;
 	bool do_print_state = false;
 
@@ -4835,19 +4834,19 @@ static int do_check(struct bpf_verifier_env *env)
 			BPF_MAIN_FUNC /* callsite */,
 			0 /* frameno */,
 			0 /* subprogno, zero == main subprog */);
-	insn_idx = 0;
+
 	for (;;) {
 		struct bpf_insn *insn;
 		u8 class;
 		int err;
 
-		if (insn_idx >= insn_cnt) {
+		if (env->insn_idx >= insn_cnt) {
 			verbose(env, "invalid insn idx %d insn_cnt %d\n",
-				insn_idx, insn_cnt);
+				env->insn_idx, insn_cnt);
 			return -EFAULT;
 		}
 
-		insn = &insns[insn_idx];
+		insn = &insns[env->insn_idx];
 		class = BPF_CLASS(insn->code);
 
 		if (++insn_processed > BPF_COMPLEXITY_LIMIT_INSNS) {
@@ -4857,7 +4856,7 @@ static int do_check(struct bpf_verifier_env *env)
 			return -E2BIG;
 		}
 
-		err = is_state_visited(env, insn_idx);
+		err = is_state_visited(env, env->insn_idx);
 		if (err < 0)
 			return err;
 		if (err == 1) {
@@ -4865,9 +4864,9 @@ static int do_check(struct bpf_verifier_env *env)
 			if (env->log.level) {
 				if (do_print_state)
 					verbose(env, "\nfrom %d to %d: safe\n",
-						prev_insn_idx, insn_idx);
+						env->prev_insn_idx, env->insn_idx);
 				else
-					verbose(env, "%d: safe\n", insn_idx);
+					verbose(env, "%d: safe\n", env->insn_idx);
 			}
 			goto process_bpf_exit;
 		}
@@ -4880,10 +4879,10 @@ static int do_check(struct bpf_verifier_env *env)
 
 		if (env->log.level > 1 || (env->log.level && do_print_state)) {
 			if (env->log.level > 1)
-				verbose(env, "%d:", insn_idx);
+				verbose(env, "%d:", env->insn_idx);
 			else
 				verbose(env, "\nfrom %d to %d:",
-					prev_insn_idx, insn_idx);
+					env->prev_insn_idx, env->insn_idx);
 			print_verifier_state(env, state->frame[state->curframe]);
 			do_print_state = false;
 		}
@@ -4894,19 +4893,20 @@ static int do_check(struct bpf_verifier_env *env)
 				.private_data	= env,
 			};
 
-			verbose(env, "%d: ", insn_idx);
+			verbose(env, "%d: ", env->insn_idx);
 			print_bpf_insn(&cbs, insn, env->allow_ptr_leaks);
 		}
 
 		if (bpf_prog_is_dev_bound(env->prog->aux)) {
-			err = bpf_prog_offload_verify_insn(env, insn_idx,
-							   prev_insn_idx);
+			err = bpf_prog_offload_verify_insn(env, env->insn_idx,
+							   env->prev_insn_idx);
 			if (err)
 				return err;
 		}
 
 		regs = cur_regs(env);
-		env->insn_aux_data[insn_idx].seen = true;
+		env->insn_aux_data[env->insn_idx].seen = true;
+
 		if (class == BPF_ALU || class == BPF_ALU64) {
 			err = check_alu_op(env, insn);
 			if (err)
@@ -4931,13 +4931,13 @@ static int do_check(struct bpf_verifier_env *env)
 			/* check that memory (src_reg + off) is readable,
 			 * the state of dst_reg will be updated by this func
 			 */
-			err = check_mem_access(env, insn_idx, insn->src_reg, insn->off,
-					       BPF_SIZE(insn->code), BPF_READ,
-					       insn->dst_reg, false);
+			err = check_mem_access(env, env->insn_idx, insn->src_reg,
+					       insn->off, BPF_SIZE(insn->code),
+					       BPF_READ, insn->dst_reg, false);
 			if (err)
 				return err;
 
-			prev_src_type = &env->insn_aux_data[insn_idx].ptr_type;
+			prev_src_type = &env->insn_aux_data[env->insn_idx].ptr_type;
 
 			if (*prev_src_type == NOT_INIT) {
 				/* saw a valid insn
@@ -4964,10 +4964,10 @@ static int do_check(struct bpf_verifier_env *env)
 			enum bpf_reg_type *prev_dst_type, dst_reg_type;
 
 			if (BPF_MODE(insn->code) == BPF_XADD) {
-				err = check_xadd(env, insn_idx, insn);
+				err = check_xadd(env, env->insn_idx, insn);
 				if (err)
 					return err;
-				insn_idx++;
+				env->insn_idx++;
 				continue;
 			}
 
@@ -4983,13 +4983,13 @@ static int do_check(struct bpf_verifier_env *env)
 			dst_reg_type = regs[insn->dst_reg].type;
 
 			/* check that memory (dst_reg + off) is writeable */
-			err = check_mem_access(env, insn_idx, insn->dst_reg, insn->off,
-					       BPF_SIZE(insn->code), BPF_WRITE,
-					       insn->src_reg, false);
+			err = check_mem_access(env, env->insn_idx, insn->dst_reg,
+					       insn->off, BPF_SIZE(insn->code),
+					       BPF_WRITE, insn->src_reg, false);
 			if (err)
 				return err;
 
-			prev_dst_type = &env->insn_aux_data[insn_idx].ptr_type;
+			prev_dst_type = &env->insn_aux_data[env->insn_idx].ptr_type;
 
 			if (*prev_dst_type == NOT_INIT) {
 				*prev_dst_type = dst_reg_type;
@@ -5018,9 +5018,9 @@ static int do_check(struct bpf_verifier_env *env)
 			}
 
 			/* check that memory (dst_reg + off) is writeable */
-			err = check_mem_access(env, insn_idx, insn->dst_reg, insn->off,
-					       BPF_SIZE(insn->code), BPF_WRITE,
-					       -1, false);
+			err = check_mem_access(env, env->insn_idx, insn->dst_reg,
+					       insn->off, BPF_SIZE(insn->code),
+					       BPF_WRITE, -1, false);
 			if (err)
 				return err;
 
@@ -5038,9 +5038,9 @@ static int do_check(struct bpf_verifier_env *env)
 				}
 
 				if (insn->src_reg == BPF_PSEUDO_CALL)
-					err = check_func_call(env, insn, &insn_idx);
+					err = check_func_call(env, insn, &env->insn_idx);
 				else
-					err = check_helper_call(env, insn->imm, insn_idx);
+					err = check_helper_call(env, insn->imm, env->insn_idx);
 				if (err)
 					return err;
 
@@ -5053,7 +5053,7 @@ static int do_check(struct bpf_verifier_env *env)
 					return -EINVAL;
 				}
 
-				insn_idx += insn->off + 1;
+				env->insn_idx += insn->off + 1;
 				continue;
 
 			} else if (opcode == BPF_EXIT) {
@@ -5067,8 +5067,8 @@ static int do_check(struct bpf_verifier_env *env)
 
 				if (state->curframe) {
 					/* exit from nested function */
-					prev_insn_idx = insn_idx;
-					err = prepare_func_exit(env, &insn_idx);
+					env->prev_insn_idx = env->insn_idx;
+					err = prepare_func_exit(env, &env->insn_idx);
 					if (err)
 						return err;
 					do_print_state = true;
@@ -5094,7 +5094,8 @@ static int do_check(struct bpf_verifier_env *env)
 				if (err)
 					return err;
 process_bpf_exit:
-				err = pop_stack(env, &prev_insn_idx, &insn_idx);
+				err = pop_stack(env, &env->prev_insn_idx,
+						&env->insn_idx);
 				if (err < 0) {
 					if (err != -ENOENT)
 						return err;
@@ -5104,7 +5105,7 @@ static int do_check(struct bpf_verifier_env *env)
 					continue;
 				}
 			} else {
-				err = check_cond_jmp_op(env, insn, &insn_idx);
+				err = check_cond_jmp_op(env, insn, &env->insn_idx);
 				if (err)
 					return err;
 			}
@@ -5121,8 +5122,8 @@ static int do_check(struct bpf_verifier_env *env)
 				if (err)
 					return err;
 
-				insn_idx++;
-				env->insn_aux_data[insn_idx].seen = true;
+				env->insn_idx++;
+				env->insn_aux_data[env->insn_idx].seen = true;
 			} else {
 				verbose(env, "invalid BPF_LD mode\n");
 				return -EINVAL;
@@ -5132,7 +5133,7 @@ static int do_check(struct bpf_verifier_env *env)
 			return -EINVAL;
 		}
 
-		insn_idx++;
+		env->insn_idx++;
 	}
 
 	verbose(env, "processed %d insns (limit %d), stack depth ",
-- 
2.19.1



Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ