This is a note to let you know that I've just added the patch titled
bpf, selftests: Fix up some test_verifier cases for unprivileged
to the 5.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
bpf-selftests-fix-up-some-test_verifier-cases-for-unprivileged.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 0a13e3537ea67452d549a6a80da3776d6b7dedb3 Mon Sep 17 00:00:00 2001
From: Piotr Krysiuk <piotras@xxxxxxxxx>
Date: Tue, 16 Mar 2021 11:44:42 +0100
Subject: bpf, selftests: Fix up some test_verifier cases for unprivileged
From: Piotr Krysiuk <piotras@xxxxxxxxx>
commit 0a13e3537ea67452d549a6a80da3776d6b7dedb3 upstream.
Fix up test_verifier error messages for the case where the original error
message changed, or for the case where pointer alu errors differ between
privileged and unprivileged tests. Also, add alternative tests for keeping
coverage of the original verifier rejection error message (fp alu), and
newly reject map_ptr += rX where rX == 0 given we now forbid alu on these
types for unprivileged. All test_verifier cases pass after the change. The
test case fixups were kept separate to ease backporting of core changes.
Signed-off-by: Piotr Krysiuk <piotras@xxxxxxxxx>
Co-developed-by: Daniel Borkmann <daniel@xxxxxxxxxxxxx>
Signed-off-by: Daniel Borkmann <daniel@xxxxxxxxxxxxx>
Acked-by: Alexei Starovoitov <ast@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
tools/testing/selftests/bpf/verifier/bounds_deduction.c | 27 +++++++++++-----
tools/testing/selftests/bpf/verifier/unpriv.c | 15 ++++++++
tools/testing/selftests/bpf/verifier/value_ptr_arith.c | 23 +++++++++++++
3 files changed, 55 insertions(+), 10 deletions(-)
--- a/tools/testing/selftests/bpf/verifier/bounds_deduction.c
+++ b/tools/testing/selftests/bpf/verifier/bounds_deduction.c
@@ -6,8 +6,9 @@
BPF_ALU64_REG(BPF_SUB, BPF_REG_0, BPF_REG_1),
BPF_EXIT_INSN(),
},
- .result = REJECT,
+ .errstr_unpriv = "R0 tried to sub from different maps, paths, or prohibited types",
.errstr = "R0 tried to subtract pointer from scalar",
+ .result = REJECT,
},
{
"check deducing bounds from const, 2",
@@ -20,6 +21,8 @@
BPF_ALU64_REG(BPF_SUB, BPF_REG_1, BPF_REG_0),
BPF_EXIT_INSN(),
},
+ .errstr_unpriv = "R1 tried to sub from different maps, paths, or prohibited types",
+ .result_unpriv = REJECT,
.result = ACCEPT,
.retval = 1,
},
@@ -31,8 +34,9 @@
BPF_ALU64_REG(BPF_SUB, BPF_REG_0, BPF_REG_1),
BPF_EXIT_INSN(),
},
- .result = REJECT,
+ .errstr_unpriv = "R0 tried to sub from different maps, paths, or prohibited types",
.errstr = "R0 tried to subtract pointer from scalar",
+ .result = REJECT,
},
{
"check deducing bounds from const, 4",
@@ -45,6 +49,8 @@
BPF_ALU64_REG(BPF_SUB, BPF_REG_1, BPF_REG_0),
BPF_EXIT_INSN(),
},
+ .errstr_unpriv = "R1 tried to sub from different maps, paths, or prohibited types",
+ .result_unpriv = REJECT,
.result = ACCEPT,
},
{
@@ -55,8 +61,9 @@
BPF_ALU64_REG(BPF_SUB, BPF_REG_0, BPF_REG_1),
BPF_EXIT_INSN(),
},
- .result = REJECT,
+ .errstr_unpriv = "R0 tried to sub from different maps, paths, or prohibited types",
.errstr = "R0 tried to subtract pointer from scalar",
+ .result = REJECT,
},
{
"check deducing bounds from const, 6",
@@ -67,8 +74,9 @@
BPF_ALU64_REG(BPF_SUB, BPF_REG_0, BPF_REG_1),
BPF_EXIT_INSN(),
},
- .result = REJECT,
+ .errstr_unpriv = "R0 tried to sub from different maps, paths, or prohibited types",
.errstr = "R0 tried to subtract pointer from scalar",
+ .result = REJECT,
},
{
"check deducing bounds from const, 7",
@@ -80,8 +88,9 @@
offsetof(struct __sk_buff, mark)),
BPF_EXIT_INSN(),
},
- .result = REJECT,
+ .errstr_unpriv = "R1 tried to sub from different maps, paths, or prohibited types",
.errstr = "dereference of modified ctx ptr",
+ .result = REJECT,
.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
},
{
@@ -94,8 +103,9 @@
offsetof(struct __sk_buff, mark)),
BPF_EXIT_INSN(),
},
- .result = REJECT,
+ .errstr_unpriv = "R1 tried to add from different maps, paths, or prohibited types",
.errstr = "dereference of modified ctx ptr",
+ .result = REJECT,
.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
},
{
@@ -106,8 +116,9 @@
BPF_ALU64_REG(BPF_SUB, BPF_REG_0, BPF_REG_1),
BPF_EXIT_INSN(),
},
- .result = REJECT,
+ .errstr_unpriv = "R0 tried to sub from different maps, paths, or prohibited types",
.errstr = "R0 tried to subtract pointer from scalar",
+ .result = REJECT,
},
{
"check deducing bounds from const, 10",
@@ -119,6 +130,6 @@
BPF_ALU64_REG(BPF_SUB, BPF_REG_0, BPF_REG_1),
BPF_EXIT_INSN(),
},
- .result = REJECT,
.errstr = "math between ctx pointer and register with unbounded min value is not allowed",
+ .result = REJECT,
},
--- a/tools/testing/selftests/bpf/verifier/unpriv.c
+++ b/tools/testing/selftests/bpf/verifier/unpriv.c
@@ -495,7 +495,7 @@
.result = ACCEPT,
},
{
- "unpriv: adding of fp",
+ "unpriv: adding of fp, reg",
.insns = {
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_MOV64_IMM(BPF_REG_1, 0),
@@ -503,6 +503,19 @@
BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0, -8),
BPF_EXIT_INSN(),
},
+ .errstr_unpriv = "R1 tried to add from different maps, paths, or prohibited types",
+ .result_unpriv = REJECT,
+ .result = ACCEPT,
+},
+{
+ "unpriv: adding of fp, imm",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_MOV64_REG(BPF_REG_1, BPF_REG_10),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 0),
+ BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0, -8),
+ BPF_EXIT_INSN(),
+ },
.errstr_unpriv = "R1 stack pointer arithmetic goes out of range",
.result_unpriv = REJECT,
.result = ACCEPT,
--- a/tools/testing/selftests/bpf/verifier/value_ptr_arith.c
+++ b/tools/testing/selftests/bpf/verifier/value_ptr_arith.c
@@ -169,7 +169,7 @@
.fixup_map_array_48b = { 1 },
.result = ACCEPT,
.result_unpriv = REJECT,
- .errstr_unpriv = "R2 tried to add from different maps or paths",
+ .errstr_unpriv = "R2 tried to add from different maps, paths, or prohibited types",
.retval = 0,
},
{
@@ -517,6 +517,27 @@
.retval = 0xabcdef12,
},
{
+ "map access: value_ptr += N, value_ptr -= N known scalar",
+ .insns = {
+ BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
+ BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
+ BPF_LD_MAP_FD(BPF_REG_1, 0),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
+ BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 6),
+ BPF_MOV32_IMM(BPF_REG_1, 0x12345678),
+ BPF_STX_MEM(BPF_W, BPF_REG_0, BPF_REG_1, 0),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, 2),
+ BPF_MOV64_IMM(BPF_REG_1, 2),
+ BPF_ALU64_REG(BPF_SUB, BPF_REG_0, BPF_REG_1),
+ BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .fixup_map_array_48b = { 3 },
+ .result = ACCEPT,
+ .retval = 0x12345678,
+},
+{
"map access: unknown scalar += value_ptr, 1",
.insns = {
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
Patches currently in stable-queue which might be from piotras@xxxxxxxxx are
queue-5.4/bpf-fix-off-by-one-for-area-size-in-creating-mask-to-left.patch
queue-5.4/bpf-selftests-fix-up-some-test_verifier-cases-for-unprivileged.patch
queue-5.4/bpf-simplify-alu_limit-masking-for-pointer-arithmetic.patch
queue-5.4/bpf-prohibit-alu-ops-for-pointer-types-not-defining-ptr_limit.patch
queue-5.4/bpf-add-sanity-check-for-upper-ptr_limit.patch
