From 04e3dd4b3e984271eb89a2bfb61611bfa2802f5f Mon Sep 17 00:00:00 2001 From: Piotr Krysiuk Date: Tue, 16 Mar 2021 11:44:42 +0100 Subject: [PATCH] bpf, selftests: Fix up some test_verifier cases for unprivileged Origin: https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git/commit?id=0a13e3537ea67452d549a6a80da3776d6b7dedb3 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 Co-developed-by: Daniel Borkmann Signed-off-by: Daniel Borkmann Acked-by: Alexei Starovoitov Gbp-Pq: Topic bugfix/all Gbp-Pq: Name bpf-selftests-Fix-up-some-test_verifier-cases-for-un.patch --- .../selftests/bpf/verifier/bounds_deduction.c | 27 +++++++++++++------ .../testing/selftests/bpf/verifier/map_ptr.c | 4 +++ tools/testing/selftests/bpf/verifier/unpriv.c | 15 ++++++++++- .../selftests/bpf/verifier/value_ptr_arith.c | 23 +++++++++++++++- 4 files changed, 59 insertions(+), 10 deletions(-) diff --git a/tools/testing/selftests/bpf/verifier/bounds_deduction.c b/tools/testing/selftests/bpf/verifier/bounds_deduction.c index 1fd07a4f27a..c162498a64f 100644 --- 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, }, diff --git a/tools/testing/selftests/bpf/verifier/map_ptr.c b/tools/testing/selftests/bpf/verifier/map_ptr.c index 637f9293bda..92a1dc8e174 100644 --- a/tools/testing/selftests/bpf/verifier/map_ptr.c +++ b/tools/testing/selftests/bpf/verifier/map_ptr.c @@ -74,6 +74,8 @@ BPF_EXIT_INSN(), }, .fixup_map_hash_16b = { 4 }, + .result_unpriv = REJECT, + .errstr_unpriv = "R1 tried to add from different maps, paths, or prohibited types", .result = ACCEPT, }, { @@ -90,5 +92,7 @@ BPF_EXIT_INSN(), }, .fixup_map_hash_16b = { 4 }, + .result_unpriv = REJECT, + .errstr_unpriv = "R1 tried to add from different maps, paths, or prohibited types", .result = ACCEPT, }, diff --git a/tools/testing/selftests/bpf/verifier/unpriv.c b/tools/testing/selftests/bpf/verifier/unpriv.c index 91bb77c24a2..0d621c841db 100644 --- 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, diff --git a/tools/testing/selftests/bpf/verifier/value_ptr_arith.c b/tools/testing/selftests/bpf/verifier/value_ptr_arith.c index ed4e76b2464..feb91266db3 100644 --- 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, }, { @@ -516,6 +516,27 @@ .result = ACCEPT, .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 = { -- 2.30.2