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BPF map value adjust fix

PATCH In review Daniel Borkmann 3 participants 8 messages Jul 20, 2017

Subsystems (7)
Networking Network drivers Kselftest BPF +3 more subsystems
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Daniel Borkmann

author maintainer
#0 lore raw

cover BPF map value adjust fix

First patch in the series is the actual fix and the remaining patches are just updates to selftests.

Thanks!

Daniel Borkmann (4):
bpf: fix mixed signed/unsigned derived min/max value bounds
bpf: allow to specify log level and reduce it for test_verifier
bpf: fix up test cases with mixed signed/unsigned bounds
bpf: more tests for mixed signed and unsigned bounds checks

Edward Cree (1):
bpf: add test for mixed signed and unsigned bounds checks

 include/linux/bpf_verifier.h                |   1 +
 kernel/bpf/verifier.c                       | 108 ++++++-
 tools/lib/bpf/bpf.c                         |   4 +-
 tools/lib/bpf/bpf.h                         |   2 +-
 tools/testing/selftests/bpf/test_align.c    |   2 +-
 tools/testing/selftests/bpf/test_verifier.c | 480 +++++++++++++++++++++++++++-
 6 files changed, 574 insertions(+), 23 deletions(-)
Signature · 1 line
1.9.3
author maintainer
#1 lore raw

PATCH 1/5 bpf: fix mixed signed/unsigned derived min/max value bounds

Edward reported that there's an issue in min/max value bounds tracking when signed and unsigned compares both provide hints on limits when having unknown variables. E.g. a program such as the following should have been rejected:

0: (7a) *(u64 *)(r10 -8) = 0
1: (bf) r2 = r10
2: (07) r2 += -8
3: (18) r1 = 0xffff8a94cda93400
5: (85) call bpf_map_lookup_elem#1
6: (15) if r0 == 0x0 goto pc+7
R0=map_value(ks=8,vs=8,id=0),min_value=0,max_value=0 R10=fp
7: (7a) *(u64 *)(r10 -16) = -8
8: (79) r1 = *(u64 *)(r10 -16)
9: (b7) r2 = -1
10: (2d) if r1 > r2 goto pc+3 R0=map_value(ks=8,vs=8,id=0),min_value=0,max_value=0 R1=inv,min_value=0 R2=imm-1,max_value=18446744073709551615,min_align=1 R10=fp
11: (65) if r1 s> 0x1 goto pc+2 R0=map_value(ks=8,vs=8,id=0),min_value=0,max_value=0 R1=inv,min_value=0,max_value=1 R2=imm-1,max_value=18446744073709551615,min_align=1 R10=fp
12: (0f) r0 += r1
13: (72) *(u8 *)(r0 +0) = 0 R0=map_value_adj(ks=8,vs=8,id=0),min_value=0,max_value=1 R1=inv,min_value=0,max_value=1 R2=imm-1,max_value=18446744073709551615,min_align=1 R10=fp
14: (b7) r0 = 0
15: (95) exit

What happens is that in the first part ...

8: (79) r1 = *(u64 *)(r10 -16)
9: (b7) r2 = -1
10: (2d) if r1 > r2 goto pc+3

... r1 carries an unsigned value, and is compared as unsigned against a register carrying an immediate. Verifier deduces in reg_set_min_max() that since the compare is unsigned and operation is greater than (>), that in the fall-through/false case, r1's minimum bound must be 0 and maximum bound must be r2. Latter is larger than the bound and thus max value is reset back to being 'invalid' aka BPF_REGISTER_MAX_RANGE. Thus, r1 state is now 'R1=inv,min_value=0'. The subsequent test ...

11: (65) if r1 s> 0x1 goto pc+2

... is a signed compare of r1 with immediate value 1. Here, verifier deduces in reg_set_min_max() that since the compare is signed this time and operation is greater than (>), that in the fall-through/false case, we can deduce that r1's maximum bound must be 1, meaning with prior test, we result in r1 having the following state: R1=inv,min_value=0,max_value=1. Given that the actual value this holds is -8, the bounds are wrongly deduced. When this is being added to r0 which holds the map_value(_adj) type, then subsequent store access in above case will go through check_mem_access() which invokes check_map_access_adj(), that will then probe whether the map memory is in bounds based on the min_value and max_value as well as access size since the actual unknown value is min_value <= x <= max_value; commit fce366a9dd0d ("bpf, verifier: fix alu ops against map_value{, _adj} register types") provides some more explanation on the semantics.

It's worth to note in this context that in the current code, min_value and max_value tracking are used for two things, i) dynamic map value access via check_map_access_adj() and since commit 06c1c049721a ("bpf: allow helpers access to variable memory") ii) also enforced at check_helper_mem_access() when passing a memory address (pointer to packet, map value, stack) and length pair to a helper and the length in this case is an unknown value defining an access range through min_value/max_value in that case. The min_value/max_value tracking is /not/ used in the direct packet access case to track ranges. However, the issue also affects case ii), for example, the following crafted program based on the same principle must be rejected as well:

0: (b7) r2 = 0
1: (bf) r3 = r10
2: (07) r3 += -512
3: (7a) *(u64 *)(r10 -16) = -8
4: (79) r4 = *(u64 *)(r10 -16)
5: (b7) r6 = -1
6: (2d) if r4 > r6 goto pc+5
R1=ctx R2=imm0,min_value=0,max_value=0,min_align=2147483648 R3=fp-512 R4=inv,min_value=0 R6=imm-1,max_value=18446744073709551615,min_align=1 R10=fp
7: (65) if r4 s> 0x1 goto pc+4
R1=ctx R2=imm0,min_value=0,max_value=0,min_align=2147483648 R3=fp-512 R4=inv,min_value=0,max_value=1 R6=imm-1,max_value=18446744073709551615,min_align=1 R10=fp
8: (07) r4 += 1
9: (b7) r5 = 0
10: (6a) *(u16 *)(r10 -512) = 0
11: (85) call bpf_skb_load_bytes#26
12: (b7) r0 = 0
13: (95) exit

Meaning, while we initialize the max_value stack slot that the verifier thinks we access in the [1,2] range, in reality we pass -7 as length which is interpreted as u32 in the helper. Thus, this issue is relevant also for the case of helper ranges. Resetting both bounds in check_reg_overflow() in case only one of them exceeds limits is also not enough as similar test can be created that uses values which are within range, thus also here learned min value in r1 is incorrect when mixed with later signed test to create a range:

0: (7a) *(u64 *)(r10 -8) = 0
1: (bf) r2 = r10
2: (07) r2 += -8
3: (18) r1 = 0xffff880ad081fa00
5: (85) call bpf_map_lookup_elem#1
6: (15) if r0 == 0x0 goto pc+7
R0=map_value(ks=8,vs=8,id=0),min_value=0,max_value=0 R10=fp
7: (7a) *(u64 *)(r10 -16) = -8
8: (79) r1 = *(u64 *)(r10 -16)
9: (b7) r2 = 2
10: (3d) if r2 >= r1 goto pc+3 R0=map_value(ks=8,vs=8,id=0),min_value=0,max_value=0 R1=inv,min_value=3 R2=imm2,min_value=2,max_value=2,min_align=2 R10=fp
11: (65) if r1 s> 0x4 goto pc+2 R0=map_value(ks=8,vs=8,id=0),min_value=0,max_value=0 R1=inv,min_value=3,max_value=4 R2=imm2,min_value=2,max_value=2,min_align=2 R10=fp 12: (0f) r0 += r1
13: (72) *(u8 *)(r0 +0) = 0 R0=map_value_adj(ks=8,vs=8,id=0),min_value=3,max_value=4 R1=inv,min_value=3,max_value=4 R2=imm2,min_value=2,max_value=2,min_align=2 R10=fp 14: (b7) r0 = 0
15: (95) exit

This leaves us with two options for fixing this: i) to invalidate all prior learned information once we switch signed context, ii) to track min/max signed and unsigned boundaries separately as done in [0]. (Given latter introduces major changes throughout the whole verifier, it's rather net-next material, thus this patch follows option i), meaning we can derive bounds either from only signed tests or only unsigned tests.) There is still the case of adjust_reg_min_max_vals(), where we adjust bounds on ALU operations, meaning programs like the following where boundaries on the reg get mixed in context later on when bounds are merged on the dst reg must get rejected, too:

0: (7a) *(u64 *)(r10 -8) = 0
1: (bf) r2 = r10
2: (07) r2 += -8
3: (18) r1 = 0xffff89b2bf87ce00
5: (85) call bpf_map_lookup_elem#1
6: (15) if r0 == 0x0 goto pc+6
R0=map_value(ks=8,vs=8,id=0),min_value=0,max_value=0 R10=fp
7: (7a) *(u64 *)(r10 -16) = -8
8: (79) r1 = *(u64 *)(r10 -16)
9: (b7) r2 = 2
10: (3d) if r2 >= r1 goto pc+2 R0=map_value(ks=8,vs=8,id=0),min_value=0,max_value=0 R1=inv,min_value=3 R2=imm2,min_value=2,max_value=2,min_align=2 R10=fp
11: (b7) r7 = 1
12: (65) if r7 s> 0x0 goto pc+2 R0=map_value(ks=8,vs=8,id=0),min_value=0,max_value=0 R1=inv,min_value=3 R2=imm2,min_value=2,max_value=2,min_align=2 R7=imm1,max_value=0 R10=fp 13: (b7) r0 = 0
14: (95) exit

from 12 to 15: R0=map_value(ks=8,vs=8,id=0),min_value=0,max_value=0 R1=inv,min_value=3 R2=imm2,min_value=2,max_value=2,min_align=2 R7=imm1,min_value=1 R10=fp 15: (0f) r7 += r1
16: (65) if r7 s> 0x4 goto pc+2 R0=map_value(ks=8,vs=8,id=0),min_value=0,max_value=0 R1=inv,min_value=3 R2=imm2,min_value=2,max_value=2,min_align=2 R7=inv,min_value=4,max_value=4 R10=fp 17: (0f) r0 += r7
18: (72) *(u8 *)(r0 +0) = 0 R0=map_value_adj(ks=8,vs=8,id=0),min_value=4,max_value=4 R1=inv,min_value=3 R2=imm2,min_value=2,max_value=2,min_align=2 R7=inv,min_value=4,max_value=4 R10=fp 19: (b7) r0 = 0
20: (95) exit

Meaning, in adjust_reg_min_max_vals() we must also reset range values on the dst when src/dst registers have mixed signed/ unsigned derived min/max value bounds with one unbounded value as otherwise they can be added together deducing false boundaries. Once both boundaries are established from either ALU ops or compare operations w/o mixing signed/unsigned insns, then they can safely be added to other regs also having both boundaries established. Adding regs with one unbounded side to a map value where the bounded side has been learned w/o mixing ops is possible, but the resulting map value won't recover from that, meaning such op is considered invalid on the time of actual access. Invalid bounds are set on the dst reg in case i) src reg, or ii) in case dst reg already had them. The only way to recover would be to perform i) ALU ops but only 'add' is allowed on map value types or ii) comparisons, but these are disallowed on pointers in case they span a range. This is fine as only BPF_JEQ and BPF_JNE may be performed on PTR_TO_MAP_VALUE_OR_NULL registers which potentially turn them into PTR_TO_MAP_VALUE type depending on the branch, so only here min/max value cannot be invalidated for them.

In terms of state pruning, value_from_signed is considered as well in states_equal() when dealing with adjusted map values. With regards to breaking existing programs, there is a small risk, but use-cases are rather quite narrow where this could occur and mixing compares probably unlikely.

Joint work with Josef and Edward.

[0] https://lists.iovisor.org/pipermail/iovisor-dev/2017-June/000822.html

Fixes 484611357c19 ("bpf: allow access into map value arrays")
Reported-by Edward Cree <[email protected]>
Signed-off-by Daniel Borkmann <[email protected]>
Signed-off-by Edward Cree <[email protected]>
Signed-off-by Josef Bacik <[email protected]>
---
 include/linux/bpf_verifier.h |   1 +
 kernel/bpf/verifier.c        | 108 +++++++++++++++++++++++++++++++++++++------
 2 files changed, 95 insertions(+), 14 deletions(-)
include/linux/bpf_verifier.h +1 -0
index 621076f..8e5d31f 100644
@@ -43,6 +43,7 @@ struct bpf_reg_state {
 	u32 min_align;
 	u32 aux_off;
 	u32 aux_off_align;
+	bool value_from_signed;
 };
 
 enum bpf_stack_slot_type {
kernel/bpf/verifier.c +94 -14

227 lines not on this page · raw message

Signature · 1 line
1.9.3
Acked-by on v1 1/5
#2 lore raw

Re: [PATCH net 1/5] bpf: fix mixed signed/unsigned derived min/max value bounds

Quoted 4 lines · Daniel Borkmann

Edward reported that there's an issue in min/max value bounds tracking when signed and unsigned compares both provide hints on limits when having unknown variables. E.g. a program such as the following should have been rejected:

Thanks a lot for the hard work you folks have put into this set.

Acked-by Alexei Starovoitov <[email protected]>
author maintainer
#3 lore raw

PATCH 2/5 bpf: allow to specify log level and reduce it for test_verifier

In reply to Daniel Borkmann

For the test_verifier case, it's quite hard to parse log level 2 to figure out what's causing an issue when used to log level 1. We do want to use bpf_verify_program() in order to simulate some of the tests with strict alignment. So just add an argument to pass the level and put it to 1 for test_verifier.

Signed-off-by Daniel Borkmann <[email protected]>
Acked-by Alexei Starovoitov <[email protected]>
---
 tools/lib/bpf/bpf.c                         | 4 ++--
 tools/lib/bpf/bpf.h                         | 2 +-
 tools/testing/selftests/bpf/test_align.c    | 2 +-
 tools/testing/selftests/bpf/test_verifier.c | 2 +-
 4 files changed, 5 insertions(+), 5 deletions(-)
tools/lib/bpf/bpf.c +2 -2
index 7e0405e..412a7c8 100644
@@ -120,7 +120,7 @@ int bpf_load_program(enum bpf_prog_type type, const struct bpf_insn *insns,
 int bpf_verify_program(enum bpf_prog_type type, const struct bpf_insn *insns,
 		       size_t insns_cnt, int strict_alignment,
 		       const char *license, __u32 kern_version,
-		       char *log_buf, size_t log_buf_sz)
+		       char *log_buf, size_t log_buf_sz, int log_level)
 {
 	union bpf_attr attr;
 

@@ -131,7 +131,7 @@ int bpf_verify_program(enum bpf_prog_type type, const struct bpf_insn *insns,
 	attr.license = ptr_to_u64(license);
 	attr.log_buf = ptr_to_u64(log_buf);
 	attr.log_size = log_buf_sz;
-	attr.log_level = 2;
+	attr.log_level = log_level;
 	log_buf[0] = 0;
 	attr.kern_version = kern_version;
 	attr.prog_flags = strict_alignment ? BPF_F_STRICT_ALIGNMENT : 0;
tools/lib/bpf/bpf.h +1 -1
index 16de44a..418c86e 100644
@@ -38,7 +38,7 @@ int bpf_load_program(enum bpf_prog_type type, const struct bpf_insn *insns,
 int bpf_verify_program(enum bpf_prog_type type, const struct bpf_insn *insns,
 		       size_t insns_cnt, int strict_alignment,
 		       const char *license, __u32 kern_version,
-		       char *log_buf, size_t log_buf_sz);
+		       char *log_buf, size_t log_buf_sz, int log_level);
 
 int bpf_map_update_elem(int fd, const void *key, const void *value,
 			__u64 flags);
tools/testing/selftests/bpf/test_align.c +1 -1
index bccebd9..2979369 100644
@@ -380,7 +380,7 @@ static int do_test_single(struct bpf_align_test *test)
 	prog_len = probe_filter_length(prog);
 	fd_prog = bpf_verify_program(prog_type ? : BPF_PROG_TYPE_SOCKET_FILTER,
 				     prog, prog_len, 1, "GPL", 0,
-				     bpf_vlog, sizeof(bpf_vlog));
+				     bpf_vlog, sizeof(bpf_vlog), 2);
 	if (fd_prog < 0) {
 		printf("Failed to load program.\n");
 		printf("%s", bpf_vlog);
tools/testing/selftests/bpf/test_verifier.c +1 -1
index 404aec5..f4d0a1d 100644
@@ -5633,7 +5633,7 @@ static void do_test_single(struct bpf_test *test, bool unpriv,
 
 	fd_prog = bpf_verify_program(prog_type ? : BPF_PROG_TYPE_SOCKET_FILTER,
 				     prog, prog_len, test->flags & F_LOAD_WITH_STRICT_ALIGNMENT,
-				     "GPL", 0, bpf_vlog, sizeof(bpf_vlog));
+				     "GPL", 0, bpf_vlog, sizeof(bpf_vlog), 1);
 
 	expected_ret = unpriv && test->result_unpriv != UNDEF ?
 		       test->result_unpriv : test->result;
Signature · 1 line
1.9.3
author maintainer
#4 lore raw

PATCH 3/5 bpf: fix up test cases with mixed signed/unsigned bounds

In reply to Daniel Borkmann

Fix the few existing test cases that used mixed signed/unsigned bounds and switch them only to one flavor. Reason why we need this is that proper boundaries cannot be derived from mixed tests.

Signed-off-by Daniel Borkmann <[email protected]>
Acked-by Alexei Starovoitov <[email protected]>
---
 tools/testing/selftests/bpf/test_verifier.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)
tools/testing/selftests/bpf/test_verifier.c +4 -4
index f4d0a1d..64b39d3 100644
@@ -4969,7 +4969,7 @@ struct test_val {
 			BPF_JMP_IMM(BPF_JSGT, BPF_REG_2,
 				sizeof(struct test_val), 4),
 			BPF_MOV64_IMM(BPF_REG_4, 0),
-			BPF_JMP_REG(BPF_JGE, BPF_REG_4, BPF_REG_2, 2),
+			BPF_JMP_REG(BPF_JSGE, BPF_REG_4, BPF_REG_2, 2),
 			BPF_MOV64_IMM(BPF_REG_3, 0),
 			BPF_EMIT_CALL(BPF_FUNC_probe_read),
 			BPF_MOV64_IMM(BPF_REG_0, 0),

@@ -4995,7 +4995,7 @@ struct test_val {
 			BPF_JMP_IMM(BPF_JSGT, BPF_REG_2,
 				sizeof(struct test_val) + 1, 4),
 			BPF_MOV64_IMM(BPF_REG_4, 0),
-			BPF_JMP_REG(BPF_JGE, BPF_REG_4, BPF_REG_2, 2),
+			BPF_JMP_REG(BPF_JSGE, BPF_REG_4, BPF_REG_2, 2),
 			BPF_MOV64_IMM(BPF_REG_3, 0),
 			BPF_EMIT_CALL(BPF_FUNC_probe_read),
 			BPF_MOV64_IMM(BPF_REG_0, 0),

@@ -5023,7 +5023,7 @@ struct test_val {
 			BPF_JMP_IMM(BPF_JSGT, BPF_REG_2,
 				sizeof(struct test_val) - 20, 4),
 			BPF_MOV64_IMM(BPF_REG_4, 0),
-			BPF_JMP_REG(BPF_JGE, BPF_REG_4, BPF_REG_2, 2),
+			BPF_JMP_REG(BPF_JSGE, BPF_REG_4, BPF_REG_2, 2),
 			BPF_MOV64_IMM(BPF_REG_3, 0),
 			BPF_EMIT_CALL(BPF_FUNC_probe_read),
 			BPF_MOV64_IMM(BPF_REG_0, 0),

@@ -5050,7 +5050,7 @@ struct test_val {
 			BPF_JMP_IMM(BPF_JSGT, BPF_REG_2,
 				sizeof(struct test_val) - 19, 4),
 			BPF_MOV64_IMM(BPF_REG_4, 0),
-			BPF_JMP_REG(BPF_JGE, BPF_REG_4, BPF_REG_2, 2),
+			BPF_JMP_REG(BPF_JSGE, BPF_REG_4, BPF_REG_2, 2),
 			BPF_MOV64_IMM(BPF_REG_3, 0),
 			BPF_EMIT_CALL(BPF_FUNC_probe_read),
 			BPF_MOV64_IMM(BPF_REG_0, 0),
Signature · 1 line
1.9.3
author maintainer
#5 lore raw

PATCH 4/5 bpf: add test for mixed signed and unsigned bounds checks

In reply to Daniel Borkmann

From: Edward Cree <[email protected]>

These failed due to a bug in verifier bounds handling.

Signed-off-by Edward Cree <[email protected]>
Acked-by Daniel Borkmann <[email protected]>
Acked-by Alexei Starovoitov <[email protected]>
---
 tools/testing/selftests/bpf/test_verifier.c | 52 +++++++++++++++++++++++++++++
 1 file changed, 52 insertions(+)
tools/testing/selftests/bpf/test_verifier.c +52 -0
index 64b39d3..48b7997 100644
@@ -5510,6 +5510,58 @@ struct test_val {
 		.errstr = "invalid bpf_context access",
 		.prog_type = BPF_PROG_TYPE_LWT_IN,
 	},
+	{
+		"bounds checks mixing signed and unsigned, positive bounds",
+		.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, 7),
+			BPF_ST_MEM(BPF_DW, BPF_REG_10, -16, -8),
+			BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_10, -16),
+			BPF_MOV64_IMM(BPF_REG_2, 2),
+			BPF_JMP_REG(BPF_JGE, BPF_REG_2, BPF_REG_1, 3),
+			BPF_JMP_IMM(BPF_JSGT, BPF_REG_1, 4, 2),
+			BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_1),
+			BPF_ST_MEM(BPF_B, BPF_REG_0, 0, 0),
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+		},
+		.fixup_map1 = { 3 },
+		.errstr_unpriv = "R0 pointer arithmetic prohibited",
+		.errstr = "R0 min value is negative",
+		.result = REJECT,
+		.result_unpriv = REJECT,
+	},
+	{
+		"bounds checks mixing signed and unsigned",
+		.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, 7),
+			BPF_ST_MEM(BPF_DW, BPF_REG_10, -16, -8),
+			BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_10, -16),
+			BPF_MOV64_IMM(BPF_REG_2, -1),
+			BPF_JMP_REG(BPF_JGT, BPF_REG_1, BPF_REG_2, 3),
+			BPF_JMP_IMM(BPF_JSGT, BPF_REG_1, 1, 2),
+			BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_1),
+			BPF_ST_MEM(BPF_B, BPF_REG_0, 0, 0),
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+		},
+		.fixup_map1 = { 3 },
+		.errstr_unpriv = "R0 pointer arithmetic prohibited",
+		.errstr = "R0 min value is negative",
+		.result = REJECT,
+		.result_unpriv = REJECT,
+	},
 };
 
 static int probe_filter_length(const struct bpf_insn *fp)
Signature · 1 line
1.9.3
author maintainer
#6 lore raw

PATCH 5/5 bpf: more tests for mixed signed and unsigned bounds checks

In reply to Daniel Borkmann

Add a couple of more test cases to BPF selftests that are related to mixed signed and unsigned checks.

Signed-off-by Daniel Borkmann <[email protected]>
Acked-by Alexei Starovoitov <[email protected]>
---
 tools/testing/selftests/bpf/test_verifier.c | 418 ++++++++++++++++++++++++++++
 1 file changed, 418 insertions(+)
tools/testing/selftests/bpf/test_verifier.c +418 -0
index 48b7997..af7d173 100644
@@ -5562,6 +5562,424 @@ struct test_val {
 		.result = REJECT,
 		.result_unpriv = REJECT,
 	},
+	{
+		"bounds checks mixing signed and unsigned, variant 2",
+		.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, 9),
+			BPF_ST_MEM(BPF_DW, BPF_REG_10, -16, -8),
+			BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_10, -16),
+			BPF_MOV64_IMM(BPF_REG_2, -1),
+			BPF_JMP_REG(BPF_JGT, BPF_REG_1, BPF_REG_2, 5),
+			BPF_MOV64_IMM(BPF_REG_8, 0),
+			BPF_ALU64_REG(BPF_ADD, BPF_REG_8, BPF_REG_1),
+			BPF_JMP_IMM(BPF_JSGT, BPF_REG_8, 1, 2),
+			BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_8),
+			BPF_ST_MEM(BPF_B, BPF_REG_8, 0, 0),
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+		},
+		.fixup_map1 = { 3 },
+		.errstr_unpriv = "R0 pointer arithmetic prohibited",
+		.errstr = "R8 invalid mem access 'inv'",
+		.result = REJECT,
+		.result_unpriv = REJECT,
+	},
+	{
+		"bounds checks mixing signed and unsigned, variant 3",
+		.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, 8),
+			BPF_ST_MEM(BPF_DW, BPF_REG_10, -16, -8),
+			BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_10, -16),
+			BPF_MOV64_IMM(BPF_REG_2, -1),
+			BPF_JMP_REG(BPF_JGT, BPF_REG_1, BPF_REG_2, 4),
+			BPF_MOV64_REG(BPF_REG_8, BPF_REG_1),
+			BPF_JMP_IMM(BPF_JSGT, BPF_REG_8, 1, 2),
+			BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_8),
+			BPF_ST_MEM(BPF_B, BPF_REG_8, 0, 0),
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+		},
+		.fixup_map1 = { 3 },
+		.errstr_unpriv = "R0 pointer arithmetic prohibited",
+		.errstr = "R8 invalid mem access 'inv'",
+		.result = REJECT,
+		.result_unpriv = REJECT,
+	},
+	{
+		"bounds checks mixing signed and unsigned, variant 4",
+		.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, 7),
+			BPF_ST_MEM(BPF_DW, BPF_REG_10, -16, -8),
+			BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_10, -16),
+			BPF_MOV64_IMM(BPF_REG_2, 1),
+			BPF_ALU64_REG(BPF_AND, BPF_REG_1, BPF_REG_2),
+			BPF_JMP_IMM(BPF_JSGT, BPF_REG_1, 1, 2),
+			BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_1),
+			BPF_ST_MEM(BPF_B, BPF_REG_0, 0, 0),
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+		},
+		.fixup_map1 = { 3 },
+		.errstr_unpriv = "R0 pointer arithmetic prohibited",
+		.errstr = "R0 min value is negative",
+		.result = REJECT,
+		.result_unpriv = REJECT,
+	},
+	{
+		"bounds checks mixing signed and unsigned, variant 5",
+		.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, 9),
+			BPF_ST_MEM(BPF_DW, BPF_REG_10, -16, -8),
+			BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_10, -16),
+			BPF_MOV64_IMM(BPF_REG_2, -1),
+			BPF_JMP_REG(BPF_JGT, BPF_REG_1, BPF_REG_2, 5),
+			BPF_JMP_IMM(BPF_JSGT, BPF_REG_1, 1, 4),
+			BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, 4),
+			BPF_ALU64_REG(BPF_SUB, BPF_REG_0, BPF_REG_1),
+			BPF_ST_MEM(BPF_B, BPF_REG_0, 0, 0),
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+		},
+		.fixup_map1 = { 3 },
+		.errstr_unpriv = "R0 pointer arithmetic prohibited",
+		.errstr = "R0 invalid mem access",
+		.result = REJECT,
+		.result_unpriv = REJECT,
+	},
+	{
+		"bounds checks mixing signed and unsigned, variant 6",
+		.insns = {
+			BPF_MOV64_IMM(BPF_REG_2, 0),
+			BPF_MOV64_REG(BPF_REG_3, BPF_REG_10),
+			BPF_ALU64_IMM(BPF_ADD, BPF_REG_3, -512),
+			BPF_ST_MEM(BPF_DW, BPF_REG_10, -16, -8),
+			BPF_LDX_MEM(BPF_DW, BPF_REG_4, BPF_REG_10, -16),
+			BPF_MOV64_IMM(BPF_REG_6, -1),
+			BPF_JMP_REG(BPF_JGT, BPF_REG_4, BPF_REG_6, 5),
+			BPF_JMP_IMM(BPF_JSGT, BPF_REG_4, 1, 4),
+			BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, 1),
+			BPF_MOV64_IMM(BPF_REG_5, 0),
+			BPF_ST_MEM(BPF_H, BPF_REG_10, -512, 0),
+			BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
+				     BPF_FUNC_skb_load_bytes),
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+		},
+		.errstr_unpriv = "R4 min value is negative, either use unsigned",
+		.errstr = "R4 min value is negative, either use unsigned",
+		.result = REJECT,
+		.result_unpriv = REJECT,
+	},
+	{
+		"bounds checks mixing signed and unsigned, variant 7",
+		.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, 7),
+			BPF_ST_MEM(BPF_DW, BPF_REG_10, -16, -8),
+			BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_10, -16),
+			BPF_MOV64_IMM(BPF_REG_2, 1024 * 1024 * 1024),
+			BPF_JMP_REG(BPF_JGT, BPF_REG_1, BPF_REG_2, 3),
+			BPF_JMP_IMM(BPF_JSGT, BPF_REG_1, 1, 2),
+			BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_1),
+			BPF_ST_MEM(BPF_B, BPF_REG_0, 0, 0),
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+		},
+		.fixup_map1 = { 3 },
+		.errstr_unpriv = "R0 pointer arithmetic prohibited",
+		.errstr = "R0 min value is negative",
+		.result = REJECT,
+		.result_unpriv = REJECT,
+	},
+	{
+		"bounds checks mixing signed and unsigned, variant 8",
+		.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, 7),
+			BPF_ST_MEM(BPF_DW, BPF_REG_10, -16, -8),
+			BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_10, -16),
+			BPF_MOV64_IMM(BPF_REG_2, 1024 * 1024 * 1024 + 1),
+			BPF_JMP_REG(BPF_JGT, BPF_REG_1, BPF_REG_2, 3),
+			BPF_JMP_IMM(BPF_JSGT, BPF_REG_1, 1, 2),
+			BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_1),
+			BPF_ST_MEM(BPF_B, BPF_REG_0, 0, 0),
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+		},
+		.fixup_map1 = { 3 },
+		.errstr_unpriv = "R0 pointer arithmetic prohibited",
+		.errstr = "R0 min value is negative",
+		.result = REJECT,
+		.result_unpriv = REJECT,
+	},
+	{
+		"bounds checks mixing signed and unsigned, variant 9",
+		.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, 9),
+			BPF_ST_MEM(BPF_DW, BPF_REG_10, -16, -8),
+			BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_10, -16),
+			BPF_MOV64_IMM(BPF_REG_2, -1),
+			BPF_JMP_REG(BPF_JGT, BPF_REG_2, BPF_REG_1, 2),
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+			BPF_JMP_IMM(BPF_JSGT, BPF_REG_1, 1, 2),
+			BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_1),
+			BPF_ST_MEM(BPF_B, BPF_REG_0, 0, 0),
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+		},
+		.fixup_map1 = { 3 },
+		.errstr_unpriv = "R0 pointer arithmetic prohibited",
+		.errstr = "R0 min value is negative",
+		.result = REJECT,
+		.result_unpriv = REJECT,
+	},
+	{
+		"bounds checks mixing signed and unsigned, variant 10",
+		.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, 10),
+			BPF_ST_MEM(BPF_DW, BPF_REG_10, -16, -8),
+			BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_10, -16),
+			BPF_LD_IMM64(BPF_REG_2, -9223372036854775808ULL),
+			BPF_JMP_REG(BPF_JGT, BPF_REG_2, BPF_REG_1, 2),
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+			BPF_JMP_IMM(BPF_JSGT, BPF_REG_1, 1, 2),
+			BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_1),
+			BPF_ST_MEM(BPF_B, BPF_REG_0, 0, 0),
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+		},
+		.fixup_map1 = { 3 },
+		.errstr_unpriv = "R0 pointer arithmetic prohibited",
+		.errstr = "R0 min value is negative",
+		.result = REJECT,
+		.result_unpriv = REJECT,
+	},
+	{
+		"bounds checks mixing signed and unsigned, variant 11",
+		.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, 9),
+			BPF_ST_MEM(BPF_DW, BPF_REG_10, -16, -8),
+			BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_10, -16),
+			BPF_MOV64_IMM(BPF_REG_2, 0),
+			BPF_JMP_REG(BPF_JGT, BPF_REG_2, BPF_REG_1, 2),
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+			BPF_JMP_IMM(BPF_JSGT, BPF_REG_1, 1, 2),
+			BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_1),
+			BPF_ST_MEM(BPF_B, BPF_REG_0, 0, 0),
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+		},
+		.fixup_map1 = { 3 },
+		.errstr_unpriv = "R0 pointer arithmetic prohibited",
+		.errstr = "R0 min value is negative",
+		.result = REJECT,
+		.result_unpriv = REJECT,
+	},
+	{
+		"bounds checks mixing signed and unsigned, variant 12",
+		.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, 9),
+			BPF_ST_MEM(BPF_DW, BPF_REG_10, -16, -8),
+			BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_10, -16),
+			BPF_MOV64_IMM(BPF_REG_2, -1),
+			BPF_JMP_REG(BPF_JGE, BPF_REG_2, BPF_REG_1, 2),
+			/* Dead branch. */
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+			BPF_JMP_IMM(BPF_JSGT, BPF_REG_1, 1, 2),
+			BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_1),
+			BPF_ST_MEM(BPF_B, BPF_REG_0, 0, 0),
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+		},
+		.fixup_map1 = { 3 },
+		.errstr_unpriv = "R0 pointer arithmetic prohibited",
+		.errstr = "R0 min value is negative",
+		.result = REJECT,
+		.result_unpriv = REJECT,
+	},
+	{
+		"bounds checks mixing signed and unsigned, variant 13",
+		.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, 9),
+			BPF_ST_MEM(BPF_DW, BPF_REG_10, -16, -8),
+			BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_10, -16),
+			BPF_MOV64_IMM(BPF_REG_2, -6),
+			BPF_JMP_REG(BPF_JGE, BPF_REG_2, BPF_REG_1, 2),
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+			BPF_JMP_IMM(BPF_JSGT, BPF_REG_1, 1, 2),
+			BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_1),
+			BPF_ST_MEM(BPF_B, BPF_REG_0, 0, 0),
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+		},
+		.fixup_map1 = { 3 },
+		.errstr_unpriv = "R0 pointer arithmetic prohibited",
+		.errstr = "R0 min value is negative",
+		.result = REJECT,
+		.result_unpriv = REJECT,
+	},
+	{
+		"bounds checks mixing signed and unsigned, variant 14",
+		.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_ST_MEM(BPF_DW, BPF_REG_10, -16, -8),
+			BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_10, -16),
+			BPF_MOV64_IMM(BPF_REG_2, 2),
+			BPF_JMP_REG(BPF_JGE, BPF_REG_2, BPF_REG_1, 2),
+			BPF_MOV64_IMM(BPF_REG_7, 1),
+			BPF_JMP_IMM(BPF_JSGT, BPF_REG_7, 0, 2),
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+			BPF_ALU64_REG(BPF_ADD, BPF_REG_7, BPF_REG_1),
+			BPF_JMP_IMM(BPF_JSGT, BPF_REG_7, 4, 2),
+			BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_7),
+			BPF_ST_MEM(BPF_B, BPF_REG_0, 0, 0),
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+		},
+		.fixup_map1 = { 3 },
+		.errstr_unpriv = "R0 pointer arithmetic prohibited",
+		.errstr = "R0 min value is negative",
+		.result = REJECT,
+		.result_unpriv = REJECT,
+	},
+	{
+		"bounds checks mixing signed and unsigned, variant 15",
+		.insns = {
+			BPF_LDX_MEM(BPF_W, BPF_REG_9, BPF_REG_1,
+				    offsetof(struct __sk_buff, mark)),
+			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, 8),
+			BPF_ST_MEM(BPF_DW, BPF_REG_10, -16, -8),
+			BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_10, -16),
+			BPF_MOV64_IMM(BPF_REG_2, -1),
+			BPF_MOV64_IMM(BPF_REG_8, 2),
+			BPF_JMP_IMM(BPF_JEQ, BPF_REG_9, 42, 6),
+			BPF_JMP_REG(BPF_JSGT, BPF_REG_8, BPF_REG_1, 3),
+			BPF_JMP_IMM(BPF_JSGT, BPF_REG_1, 1, 2),
+			BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_1),
+			BPF_ST_MEM(BPF_B, BPF_REG_0, 0, 0),
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+			BPF_JMP_REG(BPF_JGT, BPF_REG_1, BPF_REG_2, -3),
+			BPF_JMP_IMM(BPF_JA, 0, 0, -7),
+		},
+		.fixup_map1 = { 4 },
+		.errstr_unpriv = "R0 pointer arithmetic prohibited",
+		.errstr = "R0 min value is negative",
+		.result = REJECT,
+		.result_unpriv = REJECT,
+	},
+	{
+		"bounds checks mixing signed and unsigned, variant 16",
+		.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, 4),
+			BPF_ST_MEM(BPF_DW, BPF_REG_10, -16, -8),
+			BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_10, -16),
+			BPF_MOV64_IMM(BPF_REG_2, -6),
+			BPF_JMP_REG(BPF_JGE, BPF_REG_2, BPF_REG_1, 2),
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+			BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_1),
+			BPF_JMP_IMM(BPF_JGT, BPF_REG_0, 1, 2),
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+			BPF_ST_MEM(BPF_B, BPF_REG_0, 0, 0),
+			BPF_MOV64_IMM(BPF_REG_0, 0),
+			BPF_EXIT_INSN(),
+		},
+		.fixup_map1 = { 3 },
+		.errstr_unpriv = "R0 pointer arithmetic prohibited",
+		.errstr = "R0 min value is negative",
+		.result = REJECT,
+		.result_unpriv = REJECT,
+	},
 };
 
 static int probe_filter_length(const struct bpf_insn *fp)
Signature · 1 line
1.9.3