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Groups > linux.kernel > #1705573 > unrolled thread
| Started by | Edward Cree <ecree@solarflare.com> |
|---|---|
| First post | 2017-08-07 16:30 +0200 |
| Last post | 2017-08-09 03:00 +0200 |
| Articles | 13 — 3 participants |
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[PATCH v5 net-next 00/12] bpf: rewrite value tracking in verifier Edward Cree <ecree@solarflare.com> - 2017-08-07 16:30 +0200
[PATCH v5 net-next 07/12] selftests/bpf: add test for bogus operations on pointers Edward Cree <ecree@solarflare.com> - 2017-08-07 16:30 +0200
[PATCH v5 net-next 03/12] bpf/verifier: more concise register state logs for constant var_off Edward Cree <ecree@solarflare.com> - 2017-08-07 16:30 +0200
[PATCH v5 net-next 05/12] selftests/bpf: rewrite test_align Edward Cree <ecree@solarflare.com> - 2017-08-07 16:30 +0200
[PATCH v5 net-next 06/12] selftests/bpf: add a test to test_align Edward Cree <ecree@solarflare.com> - 2017-08-07 16:30 +0200
[PATCH v5 net-next 08/12] selftests/bpf: don't try to access past MAX_PACKET_OFF in test_verifier Edward Cree <ecree@solarflare.com> - 2017-08-07 16:30 +0200
[PATCH v5 net-next 04/12] selftests/bpf: change test_verifier expectations Edward Cree <ecree@solarflare.com> - 2017-08-07 16:30 +0200
[PATCH v5 net-next 09/12] selftests/bpf: add tests for subtraction & negative numbers Edward Cree <ecree@solarflare.com> - 2017-08-07 16:30 +0200
[PATCH v5 net-next 11/12] Documentation: describe the new eBPF verifier value tracking behaviour Edward Cree <ecree@solarflare.com> - 2017-08-07 16:40 +0200
[PATCH v5 net-next 12/12] bpf/verifier: increase complexity limit to 128k Edward Cree <ecree@solarflare.com> - 2017-08-07 16:40 +0200
[PATCH v5 net-next 10/12] selftests/bpf: variable offset negative tests Edward Cree <ecree@solarflare.com> - 2017-08-07 16:40 +0200
Re: [PATCH v5 net-next 00/12] bpf: rewrite value tracking in verifier Daniel Borkmann <daniel@iogearbox.net> - 2017-08-08 02:50 +0200
Re: [PATCH v5 net-next 00/12] bpf: rewrite value tracking in verifier David Miller <davem@davemloft.net> - 2017-08-09 03:00 +0200
| From | Edward Cree <ecree@solarflare.com> |
|---|---|
| Date | 2017-08-07 16:30 +0200 |
| Subject | [PATCH v5 net-next 00/12] bpf: rewrite value tracking in verifier |
| Message-ID | <ubRcB-10r-7@gated-at.bofh.it> |
This series simplifies alignment tracking, generalises bounds tracking and
fixes some bounds-tracking bugs in the BPF verifier. Pointer arithmetic on
packet pointers, stack pointers, map value pointers and context pointers has
been unified, and bounds on these pointers are only checked when the pointer
is dereferenced.
Operations on pointers which destroy all relation to the original pointer
(such as multiplies and shifts) are disallowed if !env->allow_ptr_leaks,
otherwise they convert the pointer to an unknown scalar and feed it to the
normal scalar arithmetic handling.
Pointer types have been unified with the corresponding adjusted-pointer types
where those existed (e.g. PTR_TO_MAP_VALUE[_ADJ] or FRAME_PTR vs
PTR_TO_STACK); similarly, CONST_IMM and UNKNOWN_VALUE have been unified into
SCALAR_VALUE.
Pointer types (except CONST_PTR_TO_MAP, PTR_TO_MAP_VALUE_OR_NULL and
PTR_TO_PACKET_END, which do not allow arithmetic) have a 'fixed offset' and
a 'variable offset'; the former is used when e.g. adding an immediate or a
known-constant register, as long as it does not overflow. Otherwise the
latter is used, and any operation creating a new variable offset creates a
new 'id' (and, for PTR_TO_PACKET, clears the 'range').
SCALAR_VALUEs use the 'variable offset' fields to track the range of possible
values; the 'fixed offset' should never be set on a scalar.
All tests of tools/testing/selftests/bpf/test_{verifier,align,progs} pass.
v5: folded the nfp fix into patch #1; don't modify src_reg when coercing it
to 32 bits.
v4: removed some changes which were submitted separately to 'net'; altered
some of the conditional-jump bounds handling in rebasing it on Daniel's
changes. Upped the complexity limit to 128k insns.
v3: added a few more tests; removed RFC tags.
v2: fixed nfp build, made test_align pass again and extended it with a few
new tests (though still need to add more).
Edward Cree (12):
bpf/verifier: rework value tracking
bpf/verifier: track signed and unsigned min/max values
bpf/verifier: more concise register state logs for constant var_off
selftests/bpf: change test_verifier expectations
selftests/bpf: rewrite test_align
selftests/bpf: add a test to test_align
selftests/bpf: add test for bogus operations on pointers
selftests/bpf: don't try to access past MAX_PACKET_OFF in
test_verifier
selftests/bpf: add tests for subtraction & negative numbers
selftests/bpf: variable offset negative tests
Documentation: describe the new eBPF verifier value tracking behaviour
bpf/verifier: increase complexity limit to 128k
Documentation/networking/filter.txt | 122 +-
drivers/net/ethernet/netronome/nfp/bpf/verifier.c | 24 +-
include/linux/bpf.h | 34 +-
include/linux/bpf_verifier.h | 55 +-
include/linux/tnum.h | 81 +
kernel/bpf/Makefile | 2 +-
kernel/bpf/tnum.c | 180 ++
kernel/bpf/verifier.c | 2149 ++++++++++++---------
tools/testing/selftests/bpf/test_align.c | 462 ++++-
tools/testing/selftests/bpf/test_verifier.c | 389 ++--
10 files changed, 2217 insertions(+), 1281 deletions(-)
create mode 100644 include/linux/tnum.h
create mode 100644 kernel/bpf/tnum.c
[toc] | [next] | [standalone]
| From | Edward Cree <ecree@solarflare.com> |
|---|---|
| Date | 2017-08-07 16:30 +0200 |
| Subject | [PATCH v5 net-next 07/12] selftests/bpf: add test for bogus operations on pointers |
| Message-ID | <ubRcC-10r-17@gated-at.bofh.it> |
| In reply to | #1705573 |
Tests non-add/sub operations (AND, LSH) on pointers decaying them to
unknown scalars.
Also tests that a pkt_ptr add which could potentially overflow is rejected
(find_good_pkt_pointers ignores it and doesn't give us any reg->range).
Signed-off-by: Edward Cree <ecree@solarflare.com>
---
tools/testing/selftests/bpf/test_align.c | 66 +++++++++++++++++++++++++++++++-
1 file changed, 64 insertions(+), 2 deletions(-)
diff --git a/tools/testing/selftests/bpf/test_align.c b/tools/testing/selftests/bpf/test_align.c
index 74cc4a6..b081683 100644
--- a/tools/testing/selftests/bpf/test_align.c
+++ b/tools/testing/selftests/bpf/test_align.c
@@ -441,6 +441,62 @@ static struct bpf_align_test tests[] = {
{23, "R5=pkt(id=2,off=0,r=4,umin_value=14,umax_value=2054,var_off=(0x2; 0xffc))"},
},
},
+ {
+ .descr = "dubious pointer arithmetic",
+ .insns = {
+ PREP_PKT_POINTERS,
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ /* ptr & const => unknown & const */
+ BPF_MOV64_REG(BPF_REG_5, BPF_REG_2),
+ BPF_ALU64_IMM(BPF_AND, BPF_REG_5, 0x40),
+ /* ptr << const => unknown << const */
+ BPF_MOV64_REG(BPF_REG_5, BPF_REG_2),
+ BPF_ALU64_IMM(BPF_LSH, BPF_REG_5, 2),
+ /* We have a (4n) value. Let's make a packet offset
+ * out of it. First add 14, to make it a (4n+2)
+ */
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_5, 14),
+ /* Then make sure it's nonnegative */
+ BPF_JMP_IMM(BPF_JSGE, BPF_REG_5, 0, 1),
+ BPF_EXIT_INSN(),
+ /* Add it to packet pointer */
+ BPF_MOV64_REG(BPF_REG_6, BPF_REG_2),
+ BPF_ALU64_REG(BPF_ADD, BPF_REG_6, BPF_REG_5),
+ /* Check bounds and perform a read */
+ BPF_MOV64_REG(BPF_REG_4, BPF_REG_6),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, 4),
+ BPF_JMP_REG(BPF_JGE, BPF_REG_3, BPF_REG_4, 1),
+ BPF_EXIT_INSN(),
+ BPF_LDX_MEM(BPF_W, BPF_REG_4, BPF_REG_6, 0),
+ BPF_EXIT_INSN(),
+ },
+ .prog_type = BPF_PROG_TYPE_SCHED_CLS,
+ .result = REJECT,
+ .matches = {
+ {4, "R5=pkt(id=0,off=0,r=0,imm=0)"},
+ /* ptr & 0x40 == either 0 or 0x40 */
+ {5, "R5=inv(id=0,umax_value=64,var_off=(0x0; 0x40))"},
+ /* ptr << 2 == unknown, (4n) */
+ {7, "R5=inv(id=0,smax_value=9223372036854775804,umax_value=18446744073709551612,var_off=(0x0; 0xfffffffffffffffc))"},
+ /* (4n) + 14 == (4n+2). We blow our bounds, because
+ * the add could overflow.
+ */
+ {8, "R5=inv(id=0,var_off=(0x2; 0xfffffffffffffffc))"},
+ /* Checked s>=0 */
+ {10, "R5=inv(id=0,umin_value=2,umax_value=9223372036854775806,var_off=(0x2; 0x7ffffffffffffffc))"},
+ /* packet pointer + nonnegative (4n+2) */
+ {12, "R6=pkt(id=1,off=0,r=0,umin_value=2,umax_value=9223372036854775806,var_off=(0x2; 0x7ffffffffffffffc))"},
+ {14, "R4=pkt(id=1,off=4,r=0,umin_value=2,umax_value=9223372036854775806,var_off=(0x2; 0x7ffffffffffffffc))"},
+ /* NET_IP_ALIGN + (4n+2) == (4n), alignment is fine.
+ * We checked the bounds, but it might have been able
+ * to overflow if the packet pointer started in the
+ * upper half of the address space.
+ * So we did not get a 'range' on R6, and the access
+ * attempt will fail.
+ */
+ {16, "R6=pkt(id=1,off=0,r=0,umin_value=2,umax_value=9223372036854775806,var_off=(0x2; 0x7ffffffffffffffc))"},
+ }
+ },
};
static int probe_filter_length(const struct bpf_insn *fp)
@@ -470,10 +526,15 @@ static int do_test_single(struct bpf_align_test *test)
fd_prog = bpf_verify_program(prog_type ? : BPF_PROG_TYPE_SOCKET_FILTER,
prog, prog_len, 1, "GPL", 0,
bpf_vlog, sizeof(bpf_vlog), 2);
- if (fd_prog < 0) {
+ if (fd_prog < 0 && test->result != REJECT) {
printf("Failed to load program.\n");
printf("%s", bpf_vlog);
ret = 1;
+ } else if (fd_prog >= 0 && test->result == REJECT) {
+ printf("Unexpected success to load!\n");
+ printf("%s", bpf_vlog);
+ ret = 1;
+ close(fd_prog);
} else {
ret = 0;
/* We make a local copy so that we can strtok() it */
@@ -506,7 +567,8 @@ static int do_test_single(struct bpf_align_test *test)
break;
}
}
- close(fd_prog);
+ if (fd_prog >= 0)
+ close(fd_prog);
}
return ret;
}
[toc] | [prev] | [next] | [standalone]
| From | Edward Cree <ecree@solarflare.com> |
|---|---|
| Date | 2017-08-07 16:30 +0200 |
| Subject | [PATCH v5 net-next 03/12] bpf/verifier: more concise register state logs for constant var_off |
| Message-ID | <ubRcD-10r-23@gated-at.bofh.it> |
| In reply to | #1705573 |
Signed-off-by: Edward Cree <ecree@solarflare.com>
---
kernel/bpf/verifier.c | 46 +++++++++++++++++++++++++++-------------------
1 file changed, 27 insertions(+), 19 deletions(-)
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 7557800..08a6fa0 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -234,25 +234,33 @@ static void print_verifier_state(struct bpf_verifier_state *state)
verbose(",ks=%d,vs=%d",
reg->map_ptr->key_size,
reg->map_ptr->value_size);
- if (reg->smin_value != reg->umin_value &&
- reg->smin_value != S64_MIN)
- verbose(",smin_value=%lld",
- (long long)reg->smin_value);
- if (reg->smax_value != reg->umax_value &&
- reg->smax_value != S64_MAX)
- verbose(",smax_value=%lld",
- (long long)reg->smax_value);
- if (reg->umin_value != 0)
- verbose(",umin_value=%llu",
- (unsigned long long)reg->umin_value);
- if (reg->umax_value != U64_MAX)
- verbose(",umax_value=%llu",
- (unsigned long long)reg->umax_value);
- if (!tnum_is_unknown(reg->var_off)) {
- char tn_buf[48];
-
- tnum_strn(tn_buf, sizeof(tn_buf), reg->var_off);
- verbose(",var_off=%s", tn_buf);
+ if (tnum_is_const(reg->var_off)) {
+ /* Typically an immediate SCALAR_VALUE, but
+ * could be a pointer whose offset is too big
+ * for reg->off
+ */
+ verbose(",imm=%llx", reg->var_off.value);
+ } else {
+ if (reg->smin_value != reg->umin_value &&
+ reg->smin_value != S64_MIN)
+ verbose(",smin_value=%lld",
+ (long long)reg->smin_value);
+ if (reg->smax_value != reg->umax_value &&
+ reg->smax_value != S64_MAX)
+ verbose(",smax_value=%lld",
+ (long long)reg->smax_value);
+ if (reg->umin_value != 0)
+ verbose(",umin_value=%llu",
+ (unsigned long long)reg->umin_value);
+ if (reg->umax_value != U64_MAX)
+ verbose(",umax_value=%llu",
+ (unsigned long long)reg->umax_value);
+ if (!tnum_is_unknown(reg->var_off)) {
+ char tn_buf[48];
+
+ tnum_strn(tn_buf, sizeof(tn_buf), reg->var_off);
+ verbose(",var_off=%s", tn_buf);
+ }
}
verbose(")");
}
[toc] | [prev] | [next] | [standalone]
| From | Edward Cree <ecree@solarflare.com> |
|---|---|
| Date | 2017-08-07 16:30 +0200 |
| Subject | [PATCH v5 net-next 05/12] selftests/bpf: rewrite test_align |
| Message-ID | <ubRcD-10r-33@gated-at.bofh.it> |
| In reply to | #1705573 |
Expectations have changed, as has the format of the logged state.
To make the tests easier to read, add a line-matching framework so that
each match need only quote the register it cares about. (Multiple
matches may refer to the same line, but matches must be listed in
order of increasing line.)
Signed-off-by: Edward Cree <ecree@solarflare.com>
---
tools/testing/selftests/bpf/test_align.c | 225 ++++++++++++++++++-------------
1 file changed, 132 insertions(+), 93 deletions(-)
diff --git a/tools/testing/selftests/bpf/test_align.c b/tools/testing/selftests/bpf/test_align.c
index 2979369..62232e4d 100644
--- a/tools/testing/selftests/bpf/test_align.c
+++ b/tools/testing/selftests/bpf/test_align.c
@@ -27,6 +27,11 @@
#define MAX_INSNS 512
#define MAX_MATCHES 16
+struct bpf_reg_match {
+ unsigned int line;
+ const char *match;
+};
+
struct bpf_align_test {
const char *descr;
struct bpf_insn insns[MAX_INSNS];
@@ -36,10 +41,14 @@ struct bpf_align_test {
REJECT
} result;
enum bpf_prog_type prog_type;
- const char *matches[MAX_MATCHES];
+ /* Matches must be in order of increasing line */
+ struct bpf_reg_match matches[MAX_MATCHES];
};
static struct bpf_align_test tests[] = {
+ /* Four tests of known constants. These aren't staggeringly
+ * interesting since we track exact values now.
+ */
{
.descr = "mov",
.insns = {
@@ -53,11 +62,13 @@ static struct bpf_align_test tests[] = {
},
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
.matches = {
- "1: R1=ctx R3=imm2,min_value=2,max_value=2,min_align=2 R10=fp",
- "2: R1=ctx R3=imm4,min_value=4,max_value=4,min_align=4 R10=fp",
- "3: R1=ctx R3=imm8,min_value=8,max_value=8,min_align=8 R10=fp",
- "4: R1=ctx R3=imm16,min_value=16,max_value=16,min_align=16 R10=fp",
- "5: R1=ctx R3=imm32,min_value=32,max_value=32,min_align=32 R10=fp",
+ {1, "R1=ctx(id=0,off=0,imm=0)"},
+ {1, "R10=fp0"},
+ {1, "R3=inv2"},
+ {2, "R3=inv4"},
+ {3, "R3=inv8"},
+ {4, "R3=inv16"},
+ {5, "R3=inv32"},
},
},
{
@@ -79,17 +90,19 @@ static struct bpf_align_test tests[] = {
},
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
.matches = {
- "1: R1=ctx R3=imm1,min_value=1,max_value=1,min_align=1 R10=fp",
- "2: R1=ctx R3=imm2,min_value=2,max_value=2,min_align=2 R10=fp",
- "3: R1=ctx R3=imm4,min_value=4,max_value=4,min_align=4 R10=fp",
- "4: R1=ctx R3=imm8,min_value=8,max_value=8,min_align=8 R10=fp",
- "5: R1=ctx R3=imm16,min_value=16,max_value=16,min_align=16 R10=fp",
- "6: R1=ctx R3=imm1,min_value=1,max_value=1,min_align=1 R10=fp",
- "7: R1=ctx R3=imm1,min_value=1,max_value=1,min_align=1 R4=imm32,min_value=32,max_value=32,min_align=32 R10=fp",
- "8: R1=ctx R3=imm1,min_value=1,max_value=1,min_align=1 R4=imm16,min_value=16,max_value=16,min_align=16 R10=fp",
- "9: R1=ctx R3=imm1,min_value=1,max_value=1,min_align=1 R4=imm8,min_value=8,max_value=8,min_align=8 R10=fp",
- "10: R1=ctx R3=imm1,min_value=1,max_value=1,min_align=1 R4=imm4,min_value=4,max_value=4,min_align=4 R10=fp",
- "11: R1=ctx R3=imm1,min_value=1,max_value=1,min_align=1 R4=imm2,min_value=2,max_value=2,min_align=2 R10=fp",
+ {1, "R1=ctx(id=0,off=0,imm=0)"},
+ {1, "R10=fp0"},
+ {1, "R3=inv1"},
+ {2, "R3=inv2"},
+ {3, "R3=inv4"},
+ {4, "R3=inv8"},
+ {5, "R3=inv16"},
+ {6, "R3=inv1"},
+ {7, "R4=inv32"},
+ {8, "R4=inv16"},
+ {9, "R4=inv8"},
+ {10, "R4=inv4"},
+ {11, "R4=inv2"},
},
},
{
@@ -106,12 +119,14 @@ static struct bpf_align_test tests[] = {
},
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
.matches = {
- "1: R1=ctx R3=imm4,min_value=4,max_value=4,min_align=4 R10=fp",
- "2: R1=ctx R3=imm8,min_value=8,max_value=8,min_align=4 R10=fp",
- "3: R1=ctx R3=imm10,min_value=10,max_value=10,min_align=2 R10=fp",
- "4: R1=ctx R3=imm10,min_value=10,max_value=10,min_align=2 R4=imm8,min_value=8,max_value=8,min_align=8 R10=fp",
- "5: R1=ctx R3=imm10,min_value=10,max_value=10,min_align=2 R4=imm12,min_value=12,max_value=12,min_align=4 R10=fp",
- "6: R1=ctx R3=imm10,min_value=10,max_value=10,min_align=2 R4=imm14,min_value=14,max_value=14,min_align=2 R10=fp",
+ {1, "R1=ctx(id=0,off=0,imm=0)"},
+ {1, "R10=fp0"},
+ {1, "R3=inv4"},
+ {2, "R3=inv8"},
+ {3, "R3=inv10"},
+ {4, "R4=inv8"},
+ {5, "R4=inv12"},
+ {6, "R4=inv14"},
},
},
{
@@ -126,13 +141,16 @@ static struct bpf_align_test tests[] = {
},
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
.matches = {
- "1: R1=ctx R3=imm7,min_value=7,max_value=7,min_align=1 R10=fp",
- "2: R1=ctx R3=imm7,min_value=7,max_value=7,min_align=1 R10=fp",
- "3: R1=ctx R3=imm14,min_value=14,max_value=14,min_align=2 R10=fp",
- "4: R1=ctx R3=imm56,min_value=56,max_value=56,min_align=4 R10=fp",
+ {1, "R1=ctx(id=0,off=0,imm=0)"},
+ {1, "R10=fp0"},
+ {1, "R3=inv7"},
+ {2, "R3=inv7"},
+ {3, "R3=inv14"},
+ {4, "R3=inv56"},
},
},
+ /* Tests using unknown values */
#define PREP_PKT_POINTERS \
BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, \
offsetof(struct __sk_buff, data)), \
@@ -166,17 +184,19 @@ static struct bpf_align_test tests[] = {
},
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
.matches = {
- "7: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=inv56 R10=fp",
- "8: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=inv55,min_align=2 R10=fp",
- "9: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=inv54,min_align=4 R10=fp",
- "10: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=inv53,min_align=8 R10=fp",
- "11: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=inv52,min_align=16 R10=fp",
- "18: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=pkt_end R4=inv56 R10=fp",
- "19: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=pkt_end R4=inv51,min_align=32 R10=fp",
- "20: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=pkt_end R4=inv52,min_align=16 R10=fp",
- "21: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=pkt_end R4=inv53,min_align=8 R10=fp",
- "22: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=pkt_end R4=inv54,min_align=4 R10=fp",
- "23: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=pkt_end R4=inv55,min_align=2 R10=fp",
+ {7, "R0=pkt(id=0,off=8,r=8,imm=0)"},
+ {7, "R3=inv(id=0,umax_value=255,var_off=(0x0; 0xff))"},
+ {8, "R3=inv(id=0,umax_value=510,var_off=(0x0; 0x1fe))"},
+ {9, "R3=inv(id=0,umax_value=1020,var_off=(0x0; 0x3fc))"},
+ {10, "R3=inv(id=0,umax_value=2040,var_off=(0x0; 0x7f8))"},
+ {11, "R3=inv(id=0,umax_value=4080,var_off=(0x0; 0xff0))"},
+ {18, "R3=pkt_end(id=0,off=0,imm=0)"},
+ {18, "R4=inv(id=0,umax_value=255,var_off=(0x0; 0xff))"},
+ {19, "R4=inv(id=0,umax_value=8160,var_off=(0x0; 0x1fe0))"},
+ {20, "R4=inv(id=0,umax_value=4080,var_off=(0x0; 0xff0))"},
+ {21, "R4=inv(id=0,umax_value=2040,var_off=(0x0; 0x7f8))"},
+ {22, "R4=inv(id=0,umax_value=1020,var_off=(0x0; 0x3fc))"},
+ {23, "R4=inv(id=0,umax_value=510,var_off=(0x0; 0x1fe))"},
},
},
{
@@ -197,16 +217,16 @@ static struct bpf_align_test tests[] = {
},
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
.matches = {
- "7: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=inv56 R10=fp",
- "8: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=inv56 R4=inv56 R10=fp",
- "9: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=inv56 R4=inv55,min_align=1 R10=fp",
- "10: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=inv56 R4=inv56 R10=fp",
- "11: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=inv56 R4=inv54,min_align=2 R10=fp",
- "12: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=inv56 R4=inv56 R10=fp",
- "13: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=inv56 R4=inv53,min_align=4 R10=fp",
- "14: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=inv56 R4=inv56 R10=fp",
- "15: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=inv56 R4=inv52,min_align=8 R10=fp",
- "16: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=inv56 R4=inv50,min_align=8 R10=fp"
+ {7, "R3=inv(id=0,umax_value=255,var_off=(0x0; 0xff))"},
+ {8, "R4=inv(id=0,umax_value=255,var_off=(0x0; 0xff))"},
+ {9, "R4=inv(id=0,umax_value=255,var_off=(0x0; 0xff))"},
+ {10, "R4=inv(id=0,umax_value=255,var_off=(0x0; 0xff))"},
+ {11, "R4=inv(id=0,umax_value=510,var_off=(0x0; 0x1fe))"},
+ {12, "R4=inv(id=0,umax_value=255,var_off=(0x0; 0xff))"},
+ {13, "R4=inv(id=0,umax_value=1020,var_off=(0x0; 0x3fc))"},
+ {14, "R4=inv(id=0,umax_value=255,var_off=(0x0; 0xff))"},
+ {15, "R4=inv(id=0,umax_value=2040,var_off=(0x0; 0x7f8))"},
+ {16, "R4=inv(id=0,umax_value=4080,var_off=(0x0; 0xff0))"},
},
},
{
@@ -237,12 +257,14 @@ static struct bpf_align_test tests[] = {
},
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
.matches = {
- "4: R0=imm0,min_value=0,max_value=0,min_align=2147483648 R1=ctx R2=pkt(id=0,off=0,r=0) R3=pkt_end R5=pkt(id=0,off=0,r=0) R10=fp",
- "5: R0=imm0,min_value=0,max_value=0,min_align=2147483648 R1=ctx R2=pkt(id=0,off=0,r=0) R3=pkt_end R5=pkt(id=0,off=14,r=0) R10=fp",
- "6: R0=imm0,min_value=0,max_value=0,min_align=2147483648 R1=ctx R2=pkt(id=0,off=0,r=0) R3=pkt_end R4=pkt(id=0,off=14,r=0) R5=pkt(id=0,off=14,r=0) R10=fp",
- "10: R0=imm0,min_value=0,max_value=0,min_align=2147483648 R1=ctx R2=pkt(id=0,off=0,r=18) R3=pkt_end R4=inv56 R5=pkt(id=0,off=14,r=18) R10=fp",
- "14: R0=imm0,min_value=0,max_value=0,min_align=2147483648 R1=ctx R2=pkt(id=0,off=0,r=18) R3=pkt_end R4=inv48 R5=pkt(id=0,off=14,r=18) R10=fp",
- "15: R0=imm0,min_value=0,max_value=0,min_align=2147483648 R1=ctx R2=pkt(id=0,off=0,r=18) R3=pkt_end R4=inv48 R5=pkt(id=0,off=14,r=18) R10=fp",
+ {4, "R5=pkt(id=0,off=0,r=0,imm=0)"},
+ {5, "R5=pkt(id=0,off=14,r=0,imm=0)"},
+ {6, "R4=pkt(id=0,off=14,r=0,imm=0)"},
+ {10, "R2=pkt(id=0,off=0,r=18,imm=0)"},
+ {10, "R5=pkt(id=0,off=14,r=18,imm=0)"},
+ {10, "R4=inv(id=0,umax_value=255,var_off=(0x0; 0xff))"},
+ {14, "R4=inv(id=0,umax_value=65535,var_off=(0x0; 0xffff))"},
+ {15, "R4=inv(id=0,umax_value=65535,var_off=(0x0; 0xffff))"},
},
},
{
@@ -297,62 +319,59 @@ static struct bpf_align_test tests[] = {
/* Calculated offset in R6 has unknown value, but known
* alignment of 4.
*/
- "8: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=pkt_end R6=inv54,min_align=4 R10=fp",
-
- /* Offset is added to packet pointer R5, resulting in known
- * auxiliary alignment and offset.
+ {8, "R2=pkt(id=0,off=0,r=8,imm=0)"},
+ {8, "R6=inv(id=0,umax_value=1020,var_off=(0x0; 0x3fc))"},
+ /* Offset is added to packet pointer R5, resulting in
+ * known fixed offset, and variable offset from R6.
*/
- "11: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=pkt_end R5=pkt(id=1,off=0,r=0),aux_off=14,aux_off_align=4 R6=inv54,min_align=4 R10=fp",
-
+ {11, "R5=pkt(id=1,off=14,r=0,umax_value=1020,var_off=(0x0; 0x3fc))"},
/* At the time the word size load is performed from R5,
* it's total offset is NET_IP_ALIGN + reg->off (0) +
* reg->aux_off (14) which is 16. Then the variable
* offset is considered using reg->aux_off_align which
* is 4 and meets the load's requirements.
*/
- "15: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=pkt_end R4=pkt(id=1,off=4,r=4),aux_off=14,aux_off_align=4 R5=pkt(id=1,off=0,r=4),aux_off=14,aux_off_align=4 R6=inv54,min_align=4 R10=fp",
-
-
+ {15, "R4=pkt(id=1,off=18,r=18,umax_value=1020,var_off=(0x0; 0x3fc))"},
+ {15, "R5=pkt(id=1,off=14,r=18,umax_value=1020,var_off=(0x0; 0x3fc))"},
/* Variable offset is added to R5 packet pointer,
* resulting in auxiliary alignment of 4.
*/
- "18: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=pkt_end R4=inv,aux_off=14,aux_off_align=4 R5=pkt(id=2,off=0,r=0),aux_off_align=4 R6=inv54,min_align=4 R10=fp",
-
+ {18, "R5=pkt(id=2,off=0,r=0,umax_value=1020,var_off=(0x0; 0x3fc))"},
/* Constant offset is added to R5, resulting in
* reg->off of 14.
*/
- "19: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=pkt_end R4=inv,aux_off=14,aux_off_align=4 R5=pkt(id=2,off=14,r=0),aux_off_align=4 R6=inv54,min_align=4 R10=fp",
-
+ {19, "R5=pkt(id=2,off=14,r=0,umax_value=1020,var_off=(0x0; 0x3fc))"},
/* At the time the word size load is performed from R5,
- * it's total offset is NET_IP_ALIGN + reg->off (14) which
- * is 16. Then the variable offset is considered using
- * reg->aux_off_align which is 4 and meets the load's
- * requirements.
+ * its total fixed offset is NET_IP_ALIGN + reg->off
+ * (14) which is 16. Then the variable offset is 4-byte
+ * aligned, so the total offset is 4-byte aligned and
+ * meets the load's requirements.
*/
- "23: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=pkt_end R4=pkt(id=2,off=18,r=18),aux_off_align=4 R5=pkt(id=2,off=14,r=18),aux_off_align=4 R6=inv54,min_align=4 R10=fp",
-
+ {23, "R4=pkt(id=2,off=18,r=18,umax_value=1020,var_off=(0x0; 0x3fc))"},
+ {23, "R5=pkt(id=2,off=14,r=18,umax_value=1020,var_off=(0x0; 0x3fc))"},
/* Constant offset is added to R5 packet pointer,
* resulting in reg->off value of 14.
*/
- "26: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=pkt_end R4=inv,aux_off_align=4 R5=pkt(id=0,off=14,r=8) R6=inv54,min_align=4 R10=fp",
- /* Variable offset is added to R5, resulting in an
- * auxiliary offset of 14, and an auxiliary alignment of 4.
+ {26, "R5=pkt(id=0,off=14,r=8"},
+ /* Variable offset is added to R5, resulting in a
+ * variable offset of (4n).
*/
- "27: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=pkt_end R4=inv,aux_off_align=4 R5=pkt(id=3,off=0,r=0),aux_off=14,aux_off_align=4 R6=inv54,min_align=4 R10=fp",
- /* Constant is added to R5 again, setting reg->off to 4. */
- "28: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=pkt_end R4=inv,aux_off_align=4 R5=pkt(id=3,off=4,r=0),aux_off=14,aux_off_align=4 R6=inv54,min_align=4 R10=fp",
- /* And once more we add a variable, which causes an accumulation
- * of reg->off into reg->aux_off_align, with resulting value of
- * 18. The auxiliary alignment stays at 4.
+ {27, "R5=pkt(id=3,off=14,r=0,umax_value=1020,var_off=(0x0; 0x3fc))"},
+ /* Constant is added to R5 again, setting reg->off to 18. */
+ {28, "R5=pkt(id=3,off=18,r=0,umax_value=1020,var_off=(0x0; 0x3fc))"},
+ /* And once more we add a variable; resulting var_off
+ * is still (4n), fixed offset is not changed.
+ * Also, we create a new reg->id.
*/
- "29: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=pkt_end R4=inv,aux_off_align=4 R5=pkt(id=4,off=0,r=0),aux_off=18,aux_off_align=4 R6=inv54,min_align=4 R10=fp",
+ {29, "R5=pkt(id=4,off=18,r=0,umax_value=2040,var_off=(0x0; 0x7fc))"},
/* At the time the word size load is performed from R5,
- * it's total offset is NET_IP_ALIGN + reg->off (0) +
- * reg->aux_off (18) which is 20. Then the variable offset
- * is considered using reg->aux_off_align which is 4 and meets
- * the load's requirements.
+ * its total fixed offset is NET_IP_ALIGN + reg->off (18)
+ * which is 20. Then the variable offset is (4n), so
+ * the total offset is 4-byte aligned and meets the
+ * load's requirements.
*/
- "33: R0=pkt(id=0,off=8,r=8) R1=ctx R2=pkt(id=0,off=0,r=8) R3=pkt_end R4=pkt(id=4,off=4,r=4),aux_off=18,aux_off_align=4 R5=pkt(id=4,off=0,r=4),aux_off=18,aux_off_align=4 R6=inv54,min_align=4 R10=fp",
+ {33, "R4=pkt(id=4,off=22,r=22,umax_value=2040,var_off=(0x0; 0x7fc))"},
+ {33, "R5=pkt(id=4,off=18,r=22,umax_value=2040,var_off=(0x0; 0x7fc))"},
},
},
};
@@ -373,6 +392,9 @@ static int do_test_single(struct bpf_align_test *test)
{
struct bpf_insn *prog = test->insns;
int prog_type = test->prog_type;
+ char bpf_vlog_copy[32768];
+ const char *line_ptr;
+ int cur_line = -1;
int prog_len, i;
int fd_prog;
int ret;
@@ -387,14 +409,31 @@ static int do_test_single(struct bpf_align_test *test)
ret = 1;
} else {
ret = 0;
+ /* We make a local copy so that we can strtok() it */
+ strncpy(bpf_vlog_copy, bpf_vlog, sizeof(bpf_vlog_copy));
+ line_ptr = strtok(bpf_vlog_copy, "\n");
for (i = 0; i < MAX_MATCHES; i++) {
- const char *t, *m = test->matches[i];
+ struct bpf_reg_match m = test->matches[i];
- if (!m)
+ if (!m.match)
break;
- t = strstr(bpf_vlog, m);
- if (!t) {
- printf("Failed to find match: %s\n", m);
+ while (line_ptr) {
+ cur_line = -1;
+ sscanf(line_ptr, "%u: ", &cur_line);
+ if (cur_line == m.line)
+ break;
+ line_ptr = strtok(NULL, "\n");
+ }
+ if (!line_ptr) {
+ printf("Failed to find line %u for match: %s\n",
+ m.line, m.match);
+ ret = 1;
+ printf("%s", bpf_vlog);
+ break;
+ }
+ if (!strstr(line_ptr, m.match)) {
+ printf("Failed to find match %u: %s\n",
+ m.line, m.match);
ret = 1;
printf("%s", bpf_vlog);
break;
[toc] | [prev] | [next] | [standalone]
| From | Edward Cree <ecree@solarflare.com> |
|---|---|
| Date | 2017-08-07 16:30 +0200 |
| Subject | [PATCH v5 net-next 06/12] selftests/bpf: add a test to test_align |
| Message-ID | <ubRcD-10r-35@gated-at.bofh.it> |
| In reply to | #1705573 |
New test adds 14 to the unknown value before adding to the packet pointer,
meaning there's no 'fixed offset' field and instead we add into the
var_off, yielding a '4n+2' value.
Signed-off-by: Edward Cree <ecree@solarflare.com>
---
tools/testing/selftests/bpf/test_align.c | 67 ++++++++++++++++++++++++++++++++
1 file changed, 67 insertions(+)
diff --git a/tools/testing/selftests/bpf/test_align.c b/tools/testing/selftests/bpf/test_align.c
index 62232e4d..74cc4a6 100644
--- a/tools/testing/selftests/bpf/test_align.c
+++ b/tools/testing/selftests/bpf/test_align.c
@@ -374,6 +374,73 @@ static struct bpf_align_test tests[] = {
{33, "R5=pkt(id=4,off=18,r=22,umax_value=2040,var_off=(0x0; 0x7fc))"},
},
},
+ {
+ .descr = "packet variable offset 2",
+ .insns = {
+ /* Create an unknown offset, (4n+2)-aligned */
+ LOAD_UNKNOWN(BPF_REG_6),
+ BPF_ALU64_IMM(BPF_LSH, BPF_REG_6, 2),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_6, 14),
+ /* Add it to the packet pointer */
+ BPF_MOV64_REG(BPF_REG_5, BPF_REG_2),
+ BPF_ALU64_REG(BPF_ADD, BPF_REG_5, BPF_REG_6),
+ /* Check bounds and perform a read */
+ BPF_MOV64_REG(BPF_REG_4, BPF_REG_5),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, 4),
+ BPF_JMP_REG(BPF_JGE, BPF_REG_3, BPF_REG_4, 1),
+ BPF_EXIT_INSN(),
+ BPF_LDX_MEM(BPF_W, BPF_REG_6, BPF_REG_5, 0),
+ /* Make a (4n) offset from the value we just read */
+ BPF_ALU64_IMM(BPF_AND, BPF_REG_6, 0xff),
+ BPF_ALU64_IMM(BPF_LSH, BPF_REG_6, 2),
+ /* Add it to the packet pointer */
+ BPF_ALU64_REG(BPF_ADD, BPF_REG_5, BPF_REG_6),
+ /* Check bounds and perform a read */
+ BPF_MOV64_REG(BPF_REG_4, BPF_REG_5),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, 4),
+ BPF_JMP_REG(BPF_JGE, BPF_REG_3, BPF_REG_4, 1),
+ BPF_EXIT_INSN(),
+ BPF_LDX_MEM(BPF_W, BPF_REG_6, BPF_REG_5, 0),
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .prog_type = BPF_PROG_TYPE_SCHED_CLS,
+ .matches = {
+ /* Calculated offset in R6 has unknown value, but known
+ * alignment of 4.
+ */
+ {8, "R2=pkt(id=0,off=0,r=8,imm=0)"},
+ {8, "R6=inv(id=0,umax_value=1020,var_off=(0x0; 0x3fc))"},
+ /* Adding 14 makes R6 be (4n+2) */
+ {9, "R6=inv(id=0,umin_value=14,umax_value=1034,var_off=(0x2; 0x7fc))"},
+ /* Packet pointer has (4n+2) offset */
+ {11, "R5=pkt(id=1,off=0,r=0,umin_value=14,umax_value=1034,var_off=(0x2; 0x7fc))"},
+ {13, "R4=pkt(id=1,off=4,r=0,umin_value=14,umax_value=1034,var_off=(0x2; 0x7fc))"},
+ /* At the time the word size load is performed from R5,
+ * its total fixed offset is NET_IP_ALIGN + reg->off (0)
+ * which is 2. Then the variable offset is (4n+2), so
+ * the total offset is 4-byte aligned and meets the
+ * load's requirements.
+ */
+ {15, "R5=pkt(id=1,off=0,r=4,umin_value=14,umax_value=1034,var_off=(0x2; 0x7fc))"},
+ /* Newly read value in R6 was shifted left by 2, so has
+ * known alignment of 4.
+ */
+ {18, "R6=inv(id=0,umax_value=1020,var_off=(0x0; 0x3fc))"},
+ /* Added (4n) to packet pointer's (4n+2) var_off, giving
+ * another (4n+2).
+ */
+ {19, "R5=pkt(id=2,off=0,r=0,umin_value=14,umax_value=2054,var_off=(0x2; 0xffc))"},
+ {21, "R4=pkt(id=2,off=4,r=0,umin_value=14,umax_value=2054,var_off=(0x2; 0xffc))"},
+ /* At the time the word size load is performed from R5,
+ * its total fixed offset is NET_IP_ALIGN + reg->off (0)
+ * which is 2. Then the variable offset is (4n+2), so
+ * the total offset is 4-byte aligned and meets the
+ * load's requirements.
+ */
+ {23, "R5=pkt(id=2,off=0,r=4,umin_value=14,umax_value=2054,var_off=(0x2; 0xffc))"},
+ },
+ },
};
static int probe_filter_length(const struct bpf_insn *fp)
[toc] | [prev] | [next] | [standalone]
| From | Edward Cree <ecree@solarflare.com> |
|---|---|
| Date | 2017-08-07 16:30 +0200 |
| Subject | [PATCH v5 net-next 08/12] selftests/bpf: don't try to access past MAX_PACKET_OFF in test_verifier |
| Message-ID | <ubRcD-10r-39@gated-at.bofh.it> |
| In reply to | #1705573 |
A number of selftests fell foul of the changed MAX_PACKET_OFF handling.
For instance, "direct packet access: test2" was potentially reading four
bytes from pkt + 0xffff, which could take it past the verifier's limit,
causing the program to be rejected (checks against pkt_end didn't give
us any reg->range).
Increase the shifts by one so that R2 is now mask 0x7fff instead of
mask 0xffff.
Signed-off-by: Edward Cree <ecree@solarflare.com>
---
tools/testing/selftests/bpf/test_verifier.c | 16 ++++++++--------
1 file changed, 8 insertions(+), 8 deletions(-)
diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c
index 0691494..876b878 100644
--- a/tools/testing/selftests/bpf/test_verifier.c
+++ b/tools/testing/selftests/bpf/test_verifier.c
@@ -2330,8 +2330,8 @@ static struct bpf_test tests[] = {
offsetof(struct __sk_buff, data)),
BPF_ALU64_REG(BPF_ADD, BPF_REG_3, BPF_REG_4),
BPF_MOV64_REG(BPF_REG_2, BPF_REG_1),
- BPF_ALU64_IMM(BPF_LSH, BPF_REG_2, 48),
- BPF_ALU64_IMM(BPF_RSH, BPF_REG_2, 48),
+ BPF_ALU64_IMM(BPF_LSH, BPF_REG_2, 49),
+ BPF_ALU64_IMM(BPF_RSH, BPF_REG_2, 49),
BPF_ALU64_REG(BPF_ADD, BPF_REG_3, BPF_REG_2),
BPF_MOV64_REG(BPF_REG_2, BPF_REG_3),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, 8),
@@ -2710,11 +2710,11 @@ static struct bpf_test tests[] = {
BPF_MOV64_IMM(BPF_REG_0, 0xffffffff),
BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_0, -8),
BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_10, -8),
- BPF_ALU64_IMM(BPF_AND, BPF_REG_0, 0xffff),
+ BPF_ALU64_IMM(BPF_AND, BPF_REG_0, 0x7fff),
BPF_MOV64_REG(BPF_REG_4, BPF_REG_0),
BPF_ALU64_REG(BPF_ADD, BPF_REG_4, BPF_REG_2),
BPF_MOV64_REG(BPF_REG_5, BPF_REG_4),
- BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, 0xffff - 1),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, 0x7fff - 1),
BPF_JMP_REG(BPF_JGT, BPF_REG_4, BPF_REG_3, 1),
BPF_STX_MEM(BPF_DW, BPF_REG_5, BPF_REG_4, 0),
BPF_MOV64_IMM(BPF_REG_0, 0),
@@ -2736,10 +2736,10 @@ static struct bpf_test tests[] = {
BPF_MOV64_IMM(BPF_REG_4, 0xffffffff),
BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_4, -8),
BPF_LDX_MEM(BPF_DW, BPF_REG_4, BPF_REG_10, -8),
- BPF_ALU64_IMM(BPF_AND, BPF_REG_4, 0xffff),
+ BPF_ALU64_IMM(BPF_AND, BPF_REG_4, 0x7fff),
BPF_ALU64_REG(BPF_ADD, BPF_REG_4, BPF_REG_2),
BPF_MOV64_REG(BPF_REG_5, BPF_REG_4),
- BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, 0xffff - 1),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, 0x7fff - 1),
BPF_JMP_REG(BPF_JGT, BPF_REG_4, BPF_REG_3, 1),
BPF_STX_MEM(BPF_DW, BPF_REG_5, BPF_REG_4, 0),
BPF_MOV64_IMM(BPF_REG_0, 0),
@@ -2765,7 +2765,7 @@ static struct bpf_test tests[] = {
BPF_MOV64_IMM(BPF_REG_4, 0xffffffff),
BPF_STX_XADD(BPF_DW, BPF_REG_10, BPF_REG_4, -8),
BPF_LDX_MEM(BPF_DW, BPF_REG_4, BPF_REG_10, -8),
- BPF_ALU64_IMM(BPF_RSH, BPF_REG_4, 48),
+ BPF_ALU64_IMM(BPF_RSH, BPF_REG_4, 49),
BPF_ALU64_REG(BPF_ADD, BPF_REG_4, BPF_REG_2),
BPF_MOV64_REG(BPF_REG_0, BPF_REG_4),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, 2),
@@ -2820,7 +2820,7 @@ static struct bpf_test tests[] = {
BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_4),
BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_2),
BPF_MOV64_REG(BPF_REG_5, BPF_REG_0),
- BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, 0xffff - 1),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, 0x7fff - 1),
BPF_JMP_REG(BPF_JGT, BPF_REG_0, BPF_REG_3, 1),
BPF_STX_MEM(BPF_DW, BPF_REG_5, BPF_REG_0, 0),
BPF_MOV64_IMM(BPF_REG_0, 0),
[toc] | [prev] | [next] | [standalone]
| From | Edward Cree <ecree@solarflare.com> |
|---|---|
| Date | 2017-08-07 16:30 +0200 |
| Subject | [PATCH v5 net-next 04/12] selftests/bpf: change test_verifier expectations |
| Message-ID | <ubRcD-10r-41@gated-at.bofh.it> |
| In reply to | #1705573 |
Some of the verifier's error messages have changed, and some constructs
that previously couldn't be verified are now accepted.
Signed-off-by: Edward Cree <ecree@solarflare.com>
---
tools/testing/selftests/bpf/test_verifier.c | 332 +++++++++++++---------------
1 file changed, 152 insertions(+), 180 deletions(-)
diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c
index addea82..0691494 100644
--- a/tools/testing/selftests/bpf/test_verifier.c
+++ b/tools/testing/selftests/bpf/test_verifier.c
@@ -421,7 +421,7 @@ static struct bpf_test tests[] = {
BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
- .errstr_unpriv = "R1 pointer arithmetic",
+ .errstr_unpriv = "R1 subtraction from stack pointer",
.result_unpriv = REJECT,
.errstr = "R1 invalid mem access",
.result = REJECT,
@@ -603,8 +603,9 @@ static struct bpf_test tests[] = {
BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_2, -4),
BPF_EXIT_INSN(),
},
- .errstr = "misaligned access",
+ .errstr = "misaligned stack access",
.result = REJECT,
+ .flags = F_LOAD_WITH_STRICT_ALIGNMENT,
},
{
"invalid map_fd for function call",
@@ -650,8 +651,9 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.fixup_map1 = { 3 },
- .errstr = "misaligned access",
+ .errstr = "misaligned value access",
.result = REJECT,
+ .flags = F_LOAD_WITH_STRICT_ALIGNMENT,
},
{
"sometimes access memory with incorrect alignment",
@@ -672,6 +674,7 @@ static struct bpf_test tests[] = {
.errstr = "R0 invalid mem access",
.errstr_unpriv = "R0 leaks addr",
.result = REJECT,
+ .flags = F_LOAD_WITH_STRICT_ALIGNMENT,
},
{
"jump test 1",
@@ -1215,8 +1218,9 @@ static struct bpf_test tests[] = {
offsetof(struct __sk_buff, cb[0]) + 1),
BPF_EXIT_INSN(),
},
- .errstr = "misaligned access",
+ .errstr = "misaligned context access",
.result = REJECT,
+ .flags = F_LOAD_WITH_STRICT_ALIGNMENT,
},
{
"check __sk_buff->hash, offset 0, half store not permitted",
@@ -1319,8 +1323,9 @@ static struct bpf_test tests[] = {
offsetof(struct __sk_buff, cb[0]) + 2),
BPF_EXIT_INSN(),
},
- .errstr = "misaligned access",
+ .errstr = "misaligned context access",
.result = REJECT,
+ .flags = F_LOAD_WITH_STRICT_ALIGNMENT,
},
{
"check cb access: word, unaligned 2",
@@ -1330,8 +1335,9 @@ static struct bpf_test tests[] = {
offsetof(struct __sk_buff, cb[4]) + 1),
BPF_EXIT_INSN(),
},
- .errstr = "misaligned access",
+ .errstr = "misaligned context access",
.result = REJECT,
+ .flags = F_LOAD_WITH_STRICT_ALIGNMENT,
},
{
"check cb access: word, unaligned 3",
@@ -1341,8 +1347,9 @@ static struct bpf_test tests[] = {
offsetof(struct __sk_buff, cb[4]) + 2),
BPF_EXIT_INSN(),
},
- .errstr = "misaligned access",
+ .errstr = "misaligned context access",
.result = REJECT,
+ .flags = F_LOAD_WITH_STRICT_ALIGNMENT,
},
{
"check cb access: word, unaligned 4",
@@ -1352,8 +1359,9 @@ static struct bpf_test tests[] = {
offsetof(struct __sk_buff, cb[4]) + 3),
BPF_EXIT_INSN(),
},
- .errstr = "misaligned access",
+ .errstr = "misaligned context access",
.result = REJECT,
+ .flags = F_LOAD_WITH_STRICT_ALIGNMENT,
},
{
"check cb access: double",
@@ -1379,8 +1387,9 @@ static struct bpf_test tests[] = {
offsetof(struct __sk_buff, cb[1])),
BPF_EXIT_INSN(),
},
- .errstr = "misaligned access",
+ .errstr = "misaligned context access",
.result = REJECT,
+ .flags = F_LOAD_WITH_STRICT_ALIGNMENT,
},
{
"check cb access: double, unaligned 2",
@@ -1390,8 +1399,9 @@ static struct bpf_test tests[] = {
offsetof(struct __sk_buff, cb[3])),
BPF_EXIT_INSN(),
},
- .errstr = "misaligned access",
+ .errstr = "misaligned context access",
.result = REJECT,
+ .flags = F_LOAD_WITH_STRICT_ALIGNMENT,
},
{
"check cb access: double, oob 1",
@@ -1523,7 +1533,8 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.result = REJECT,
- .errstr = "misaligned access off -6 size 8",
+ .errstr = "misaligned stack access off (0x0; 0x0)+-8+2 size 8",
+ .flags = F_LOAD_WITH_STRICT_ALIGNMENT,
},
{
"PTR_TO_STACK store/load - bad alignment on reg",
@@ -1535,7 +1546,8 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.result = REJECT,
- .errstr = "misaligned access off -2 size 8",
+ .errstr = "misaligned stack access off (0x0; 0x0)+-10+8 size 8",
+ .flags = F_LOAD_WITH_STRICT_ALIGNMENT,
},
{
"PTR_TO_STACK store/load - out of bounds low",
@@ -1579,8 +1591,6 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.result = ACCEPT,
- .result_unpriv = REJECT,
- .errstr_unpriv = "R1 pointer arithmetic",
},
{
"unpriv: add pointer to pointer",
@@ -1591,7 +1601,7 @@ static struct bpf_test tests[] = {
},
.result = ACCEPT,
.result_unpriv = REJECT,
- .errstr_unpriv = "R1 pointer arithmetic",
+ .errstr_unpriv = "R1 pointer += pointer",
},
{
"unpriv: neg pointer",
@@ -1932,10 +1942,7 @@ static struct bpf_test tests[] = {
BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0, -8),
BPF_EXIT_INSN(),
},
- .errstr_unpriv = "pointer arithmetic prohibited",
- .result_unpriv = REJECT,
- .errstr = "R1 invalid mem access",
- .result = REJECT,
+ .result = ACCEPT,
},
{
"unpriv: cmp of stack pointer",
@@ -1999,7 +2006,7 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.result = REJECT,
- .errstr = "invalid stack type R3",
+ .errstr = "R4 min value is negative",
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
},
{
@@ -2016,7 +2023,7 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.result = REJECT,
- .errstr = "invalid stack type R3",
+ .errstr = "R4 min value is negative",
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
},
{
@@ -2218,7 +2225,7 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.result = REJECT,
- .errstr = "invalid stack type R3 off=-1 access_size=-1",
+ .errstr = "R4 min value is negative",
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
},
{
@@ -2235,7 +2242,7 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.result = REJECT,
- .errstr = "invalid stack type R3 off=-1 access_size=2147483647",
+ .errstr = "R4 unbounded memory access, use 'var &= const' or 'if (var < const)'",
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
},
{
@@ -2252,7 +2259,7 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.result = REJECT,
- .errstr = "invalid stack type R3 off=-512 access_size=2147483647",
+ .errstr = "R4 unbounded memory access, use 'var &= const' or 'if (var < const)'",
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
},
{
@@ -2652,7 +2659,7 @@ static struct bpf_test tests[] = {
BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, 1),
BPF_JMP_A(-6),
},
- .errstr = "misaligned packet access off 2+15+-4 size 4",
+ .errstr = "misaligned packet access off 2+(0x0; 0x0)+15+-4 size 4",
.result = REJECT,
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
.flags = F_LOAD_WITH_STRICT_ALIGNMENT,
@@ -2795,7 +2802,7 @@ static struct bpf_test tests[] = {
},
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
.result = REJECT,
- .errstr = "cannot add integer value with 47 upper zero bits to ptr_to_packet",
+ .errstr = "invalid access to packet, off=0 size=8, R5(id=1,off=0,r=0)",
},
{
"direct packet access: test24 (x += pkt_ptr, 5)",
@@ -3112,7 +3119,7 @@ static struct bpf_test tests[] = {
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
},
{
- "helper access to packet: test14, cls helper fail sub",
+ "helper access to packet: test14, cls helper ok sub",
.insns = {
BPF_LDX_MEM(BPF_W, BPF_REG_6, BPF_REG_1,
offsetof(struct __sk_buff, data)),
@@ -3132,12 +3139,36 @@ static struct bpf_test tests[] = {
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
+ .result = ACCEPT,
+ .prog_type = BPF_PROG_TYPE_SCHED_CLS,
+ },
+ {
+ "helper access to packet: test15, cls helper fail sub",
+ .insns = {
+ BPF_LDX_MEM(BPF_W, BPF_REG_6, BPF_REG_1,
+ offsetof(struct __sk_buff, data)),
+ BPF_LDX_MEM(BPF_W, BPF_REG_7, BPF_REG_1,
+ offsetof(struct __sk_buff, data_end)),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_6, 1),
+ BPF_MOV64_REG(BPF_REG_1, BPF_REG_6),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 7),
+ BPF_JMP_REG(BPF_JGT, BPF_REG_1, BPF_REG_7, 6),
+ BPF_ALU64_IMM(BPF_SUB, BPF_REG_1, 12),
+ BPF_MOV64_IMM(BPF_REG_2, 4),
+ BPF_MOV64_IMM(BPF_REG_3, 0),
+ BPF_MOV64_IMM(BPF_REG_4, 0),
+ BPF_MOV64_IMM(BPF_REG_5, 0),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
+ BPF_FUNC_csum_diff),
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ },
.result = REJECT,
- .errstr = "type=inv expected=fp",
+ .errstr = "invalid access to packet",
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
},
{
- "helper access to packet: test15, cls helper fail range 1",
+ "helper access to packet: test16, cls helper fail range 1",
.insns = {
BPF_LDX_MEM(BPF_W, BPF_REG_6, BPF_REG_1,
offsetof(struct __sk_buff, data)),
@@ -3162,7 +3193,7 @@ static struct bpf_test tests[] = {
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
},
{
- "helper access to packet: test16, cls helper fail range 2",
+ "helper access to packet: test17, cls helper fail range 2",
.insns = {
BPF_LDX_MEM(BPF_W, BPF_REG_6, BPF_REG_1,
offsetof(struct __sk_buff, data)),
@@ -3183,11 +3214,11 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.result = REJECT,
- .errstr = "invalid access to packet",
+ .errstr = "R2 min value is negative",
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
},
{
- "helper access to packet: test17, cls helper fail range 3",
+ "helper access to packet: test18, cls helper fail range 3",
.insns = {
BPF_LDX_MEM(BPF_W, BPF_REG_6, BPF_REG_1,
offsetof(struct __sk_buff, data)),
@@ -3208,11 +3239,11 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.result = REJECT,
- .errstr = "invalid access to packet",
+ .errstr = "R2 min value is negative",
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
},
{
- "helper access to packet: test18, cls helper fail range zero",
+ "helper access to packet: test19, cls helper fail range zero",
.insns = {
BPF_LDX_MEM(BPF_W, BPF_REG_6, BPF_REG_1,
offsetof(struct __sk_buff, data)),
@@ -3237,7 +3268,7 @@ static struct bpf_test tests[] = {
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
},
{
- "helper access to packet: test19, pkt end as input",
+ "helper access to packet: test20, pkt end as input",
.insns = {
BPF_LDX_MEM(BPF_W, BPF_REG_6, BPF_REG_1,
offsetof(struct __sk_buff, data)),
@@ -3262,7 +3293,7 @@ static struct bpf_test tests[] = {
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
},
{
- "helper access to packet: test20, wrong reg",
+ "helper access to packet: test21, wrong reg",
.insns = {
BPF_LDX_MEM(BPF_W, BPF_REG_6, BPF_REG_1,
offsetof(struct __sk_buff, data)),
@@ -3322,7 +3353,7 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.fixup_map2 = { 3 },
- .errstr_unpriv = "R0 pointer arithmetic prohibited",
+ .errstr_unpriv = "R0 leaks addr",
.result_unpriv = REJECT,
.result = ACCEPT,
.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
@@ -3346,7 +3377,7 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.fixup_map2 = { 3 },
- .errstr_unpriv = "R0 pointer arithmetic prohibited",
+ .errstr_unpriv = "R0 leaks addr",
.result_unpriv = REJECT,
.result = ACCEPT,
.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
@@ -3374,7 +3405,7 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.fixup_map2 = { 3 },
- .errstr_unpriv = "R0 pointer arithmetic prohibited",
+ .errstr_unpriv = "R0 leaks addr",
.result_unpriv = REJECT,
.result = ACCEPT,
.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
@@ -3415,9 +3446,7 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.fixup_map2 = { 3 },
- .errstr_unpriv = "R0 pointer arithmetic prohibited",
.errstr = "R0 min value is outside of the array range",
- .result_unpriv = REJECT,
.result = REJECT,
.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
},
@@ -3439,9 +3468,7 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.fixup_map2 = { 3 },
- .errstr_unpriv = "R0 pointer arithmetic prohibited",
- .errstr = "R0 min value is negative, either use unsigned index or do a if (index >=0) check.",
- .result_unpriv = REJECT,
+ .errstr = "R0 unbounded memory access, make sure to bounds check any array access into a map",
.result = REJECT,
.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
},
@@ -3455,7 +3482,7 @@ static struct bpf_test tests[] = {
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_LDX_MEM(BPF_W, BPF_REG_1, BPF_REG_0, 0),
+ BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0, 0),
BPF_MOV32_IMM(BPF_REG_2, MAX_ENTRIES),
BPF_JMP_REG(BPF_JSGT, BPF_REG_2, BPF_REG_1, 1),
BPF_MOV32_IMM(BPF_REG_1, 0),
@@ -3466,8 +3493,8 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.fixup_map2 = { 3 },
- .errstr_unpriv = "R0 pointer arithmetic prohibited",
- .errstr = "R0 min value is negative, either use unsigned index or do a if (index >=0) check.",
+ .errstr_unpriv = "R0 leaks addr",
+ .errstr = "R0 unbounded memory access",
.result_unpriv = REJECT,
.result = REJECT,
.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
@@ -3493,7 +3520,7 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.fixup_map2 = { 3 },
- .errstr_unpriv = "R0 pointer arithmetic prohibited",
+ .errstr_unpriv = "R0 leaks addr",
.errstr = "invalid access to map value, value_size=48 off=44 size=8",
.result_unpriv = REJECT,
.result = REJECT,
@@ -3523,8 +3550,8 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.fixup_map2 = { 3, 11 },
- .errstr_unpriv = "R0 pointer arithmetic prohibited",
- .errstr = "R0 min value is negative, either use unsigned index or do a if (index >=0) check.",
+ .errstr_unpriv = "R0 pointer += pointer",
+ .errstr = "R0 invalid mem access 'inv'",
.result_unpriv = REJECT,
.result = REJECT,
.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
@@ -3666,34 +3693,6 @@ static struct bpf_test tests[] = {
.prog_type = BPF_PROG_TYPE_SCHED_CLS
},
{
- "multiple registers share map_lookup_elem bad reg type",
- .insns = {
- BPF_MOV64_IMM(BPF_REG_1, 10),
- BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_1, -8),
- 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_MOV64_REG(BPF_REG_2, BPF_REG_0),
- BPF_MOV64_REG(BPF_REG_3, BPF_REG_0),
- BPF_MOV64_REG(BPF_REG_4, BPF_REG_0),
- BPF_MOV64_REG(BPF_REG_5, BPF_REG_0),
- BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 1),
- BPF_MOV64_IMM(BPF_REG_1, 1),
- BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 1),
- BPF_MOV64_IMM(BPF_REG_1, 2),
- BPF_JMP_IMM(BPF_JEQ, BPF_REG_3, 0, 1),
- BPF_ST_MEM(BPF_DW, BPF_REG_3, 0, 0),
- BPF_MOV64_IMM(BPF_REG_1, 3),
- BPF_EXIT_INSN(),
- },
- .fixup_map1 = { 4 },
- .result = REJECT,
- .errstr = "R3 invalid mem access 'inv'",
- .prog_type = BPF_PROG_TYPE_SCHED_CLS
- },
- {
"invalid map access from else condition",
.insns = {
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
@@ -3711,9 +3710,9 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.fixup_map2 = { 3 },
- .errstr = "R0 unbounded memory access, make sure to bounds check any array access into a map",
+ .errstr = "R0 unbounded memory access",
.result = REJECT,
- .errstr_unpriv = "R0 pointer arithmetic prohibited",
+ .errstr_unpriv = "R0 leaks addr",
.result_unpriv = REJECT,
.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
},
@@ -4091,7 +4090,7 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.fixup_map2 = { 3 },
- .errstr = "invalid access to map value, value_size=48 off=0 size=-8",
+ .errstr = "R2 min value is negative",
.result = REJECT,
.prog_type = BPF_PROG_TYPE_TRACEPOINT,
},
@@ -4157,7 +4156,7 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.fixup_map2 = { 3 },
- .errstr = "R1 min value is outside of the array range",
+ .errstr = "invalid access to map value, value_size=48 off=4 size=0",
.result = REJECT,
.prog_type = BPF_PROG_TYPE_TRACEPOINT,
},
@@ -4203,7 +4202,7 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.fixup_map2 = { 3 },
- .errstr = "invalid access to map value, value_size=48 off=4 size=-8",
+ .errstr = "R2 min value is negative",
.result = REJECT,
.prog_type = BPF_PROG_TYPE_TRACEPOINT,
},
@@ -4225,7 +4224,7 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.fixup_map2 = { 3 },
- .errstr = "R1 min value is outside of the array range",
+ .errstr = "R2 min value is negative",
.result = REJECT,
.prog_type = BPF_PROG_TYPE_TRACEPOINT,
},
@@ -4341,7 +4340,7 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.fixup_map2 = { 3 },
- .errstr = "invalid access to map value, value_size=48 off=4 size=-8",
+ .errstr = "R2 min value is negative",
.result = REJECT,
.prog_type = BPF_PROG_TYPE_TRACEPOINT,
},
@@ -4364,7 +4363,7 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.fixup_map2 = { 3 },
- .errstr = "R1 min value is outside of the array range",
+ .errstr = "R2 min value is negative",
.result = REJECT,
.prog_type = BPF_PROG_TYPE_TRACEPOINT,
},
@@ -4452,13 +4451,13 @@ static struct bpf_test tests[] = {
BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_0, 0),
BPF_ALU64_REG(BPF_ADD, BPF_REG_1, BPF_REG_3),
- BPF_MOV64_IMM(BPF_REG_2, 0),
+ BPF_MOV64_IMM(BPF_REG_2, 1),
BPF_MOV64_IMM(BPF_REG_3, 0),
BPF_EMIT_CALL(BPF_FUNC_probe_read),
BPF_EXIT_INSN(),
},
.fixup_map2 = { 3 },
- .errstr = "R1 min value is negative, either use unsigned index or do a if (index >=0) check",
+ .errstr = "R1 unbounded memory access",
.result = REJECT,
.prog_type = BPF_PROG_TYPE_TRACEPOINT,
},
@@ -4578,7 +4577,7 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.fixup_map2 = { 3 },
- .errstr_unpriv = "R0 pointer arithmetic prohibited",
+ .errstr_unpriv = "R0 leaks addr",
.result = ACCEPT,
.result_unpriv = REJECT,
.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
@@ -4606,7 +4605,7 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.fixup_map2 = { 3 },
- .errstr_unpriv = "R0 pointer arithmetic prohibited",
+ .errstr_unpriv = "R0 leaks addr",
.result = ACCEPT,
.result_unpriv = REJECT,
.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
@@ -4625,7 +4624,7 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.fixup_map2 = { 3 },
- .errstr_unpriv = "R0 pointer arithmetic prohibited",
+ .errstr_unpriv = "R0 bitwise operator &= on pointer",
.errstr = "invalid mem access 'inv'",
.result = REJECT,
.result_unpriv = REJECT,
@@ -4644,7 +4643,7 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.fixup_map2 = { 3 },
- .errstr_unpriv = "R0 pointer arithmetic prohibited",
+ .errstr_unpriv = "R0 32-bit pointer arithmetic prohibited",
.errstr = "invalid mem access 'inv'",
.result = REJECT,
.result_unpriv = REJECT,
@@ -4663,7 +4662,7 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.fixup_map2 = { 3 },
- .errstr_unpriv = "R0 pointer arithmetic prohibited",
+ .errstr_unpriv = "R0 pointer arithmetic with /= operator",
.errstr = "invalid mem access 'inv'",
.result = REJECT,
.result_unpriv = REJECT,
@@ -4706,10 +4705,8 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.fixup_map2 = { 3 },
- .errstr_unpriv = "R0 invalid mem access 'inv'",
.errstr = "R0 invalid mem access 'inv'",
.result = REJECT,
- .result_unpriv = REJECT,
},
{
"map element value is preserved across register spilling",
@@ -4731,7 +4728,7 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.fixup_map2 = { 3 },
- .errstr_unpriv = "R0 pointer arithmetic prohibited",
+ .errstr_unpriv = "R0 leaks addr",
.result = ACCEPT,
.result_unpriv = REJECT,
.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
@@ -4913,7 +4910,8 @@ static struct bpf_test tests[] = {
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
- .errstr = "R2 unbounded memory access",
+ /* because max wasn't checked, signed min is negative */
+ .errstr = "R2 min value is negative, either use unsigned or 'var &= const'",
.result = REJECT,
.prog_type = BPF_PROG_TYPE_TRACEPOINT,
},
@@ -5062,6 +5060,20 @@ static struct bpf_test tests[] = {
.prog_type = BPF_PROG_TYPE_TRACEPOINT,
},
{
+ "helper access to variable memory: size = 0 allowed on NULL",
+ .insns = {
+ BPF_MOV64_IMM(BPF_REG_1, 0),
+ BPF_MOV64_IMM(BPF_REG_2, 0),
+ BPF_MOV64_IMM(BPF_REG_3, 0),
+ BPF_MOV64_IMM(BPF_REG_4, 0),
+ BPF_MOV64_IMM(BPF_REG_5, 0),
+ BPF_EMIT_CALL(BPF_FUNC_csum_diff),
+ BPF_EXIT_INSN(),
+ },
+ .result = ACCEPT,
+ .prog_type = BPF_PROG_TYPE_SCHED_CLS,
+ },
+ {
"helper access to variable memory: size > 0 not allowed on NULL",
.insns = {
BPF_MOV64_IMM(BPF_REG_1, 0),
@@ -5075,7 +5087,7 @@ static struct bpf_test tests[] = {
BPF_EMIT_CALL(BPF_FUNC_csum_diff),
BPF_EXIT_INSN(),
},
- .errstr = "R1 type=imm expected=fp",
+ .errstr = "R1 type=inv expected=fp",
.result = REJECT,
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
},
@@ -5160,7 +5172,7 @@ static struct bpf_test tests[] = {
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_MOV64_IMM(BPF_REG_1, 6),
+ BPF_LDX_MEM(BPF_B, BPF_REG_1, BPF_REG_0, 0),
BPF_ALU64_IMM(BPF_AND, BPF_REG_1, -4),
BPF_ALU64_IMM(BPF_LSH, BPF_REG_1, 2),
BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_1),
@@ -5169,10 +5181,8 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.fixup_map2 = { 3 },
- .errstr_unpriv = "R0 pointer arithmetic prohibited",
- .errstr = "R0 min value is negative, either use unsigned index or do a if (index >=0) check.",
+ .errstr = "R0 max value is outside of the array range",
.result = REJECT,
- .result_unpriv = REJECT,
.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
},
{
@@ -5201,10 +5211,8 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.fixup_map2 = { 3 },
- .errstr_unpriv = "R0 pointer arithmetic prohibited",
- .errstr = "R0 min value is negative, either use unsigned index or do a if (index >=0) check.",
+ .errstr = "R0 max value is outside of the array range",
.result = REJECT,
- .result_unpriv = REJECT,
.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
},
{
@@ -5251,7 +5259,7 @@ static struct bpf_test tests[] = {
},
.fixup_map_in_map = { 3 },
.errstr = "R1 type=inv expected=map_ptr",
- .errstr_unpriv = "R1 pointer arithmetic prohibited",
+ .errstr_unpriv = "R1 pointer arithmetic on CONST_PTR_TO_MAP prohibited",
.result = REJECT,
},
{
@@ -5531,10 +5539,8 @@ static struct bpf_test tests[] = {
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",
@@ -5557,10 +5563,8 @@ static struct bpf_test tests[] = {
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 2",
@@ -5585,10 +5589,8 @@ static struct bpf_test tests[] = {
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",
@@ -5612,10 +5614,8 @@ static struct bpf_test tests[] = {
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",
@@ -5638,10 +5638,7 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.fixup_map1 = { 3 },
- .errstr_unpriv = "R0 pointer arithmetic prohibited",
- .errstr = "R0 min value is negative",
- .result = REJECT,
- .result_unpriv = REJECT,
+ .result = ACCEPT,
},
{
"bounds checks mixing signed and unsigned, variant 5",
@@ -5665,10 +5662,8 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.fixup_map1 = { 3 },
- .errstr_unpriv = "R0 pointer arithmetic prohibited",
- .errstr = "R0 invalid mem access",
+ .errstr = "R0 min value is negative",
.result = REJECT,
- .result_unpriv = REJECT,
},
{
"bounds checks mixing signed and unsigned, variant 6",
@@ -5689,10 +5684,8 @@ static struct bpf_test tests[] = {
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",
@@ -5715,10 +5708,7 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.fixup_map1 = { 3 },
- .errstr_unpriv = "R0 pointer arithmetic prohibited",
- .errstr = "R0 min value is negative",
- .result = REJECT,
- .result_unpriv = REJECT,
+ .result = ACCEPT,
},
{
"bounds checks mixing signed and unsigned, variant 8",
@@ -5729,32 +5719,6 @@ static struct bpf_test tests[] = {
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),
@@ -5769,13 +5733,11 @@ static struct bpf_test tests[] = {
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",
+ "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),
@@ -5797,13 +5759,10 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.fixup_map1 = { 3 },
- .errstr_unpriv = "R0 pointer arithmetic prohibited",
- .errstr = "R0 min value is negative",
- .result = REJECT,
- .result_unpriv = REJECT,
+ .result = ACCEPT,
},
{
- "bounds checks mixing signed and unsigned, variant 11",
+ "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),
@@ -5825,13 +5784,11 @@ static struct bpf_test tests[] = {
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",
+ "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),
@@ -5854,13 +5811,11 @@ static struct bpf_test tests[] = {
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",
+ "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),
@@ -5882,13 +5837,11 @@ static struct bpf_test tests[] = {
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",
+ "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),
@@ -5913,13 +5866,11 @@ static struct bpf_test tests[] = {
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",
+ "bounds checks mixing signed and unsigned, variant 14",
.insns = {
BPF_LDX_MEM(BPF_W, BPF_REG_9, BPF_REG_1,
offsetof(struct __sk_buff, mark)),
@@ -5945,13 +5896,11 @@ static struct bpf_test tests[] = {
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",
+ "bounds checks mixing signed and unsigned, variant 15",
.insns = {
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
@@ -5975,13 +5924,13 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.fixup_map1 = { 3 },
- .errstr_unpriv = "R0 pointer arithmetic prohibited",
+ .errstr_unpriv = "R0 pointer comparison prohibited",
.errstr = "R0 min value is negative",
.result = REJECT,
.result_unpriv = REJECT,
},
{
- "subtraction bounds (map value)",
+ "subtraction bounds (map value) variant 1",
.insns = {
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
@@ -6003,10 +5952,33 @@ static struct bpf_test tests[] = {
BPF_EXIT_INSN(),
},
.fixup_map1 = { 3 },
- .errstr_unpriv = "R0 pointer arithmetic prohibited",
+ .errstr = "R0 max value is outside of the array range",
+ .result = REJECT,
+ },
+ {
+ "subtraction bounds (map value) 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, 8),
+ BPF_LDX_MEM(BPF_B, BPF_REG_1, BPF_REG_0, 0),
+ BPF_JMP_IMM(BPF_JGT, BPF_REG_1, 0xff, 6),
+ BPF_LDX_MEM(BPF_B, BPF_REG_3, BPF_REG_0, 1),
+ BPF_JMP_IMM(BPF_JGT, BPF_REG_3, 0xff, 4),
+ BPF_ALU64_REG(BPF_SUB, BPF_REG_1, BPF_REG_3),
+ BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_1),
+ BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .fixup_map1 = { 3 },
.errstr = "R0 min value is negative, either use unsigned index or do a if (index >=0) check.",
.result = REJECT,
- .result_unpriv = REJECT,
},
};
[toc] | [prev] | [next] | [standalone]
| From | Edward Cree <ecree@solarflare.com> |
|---|---|
| Date | 2017-08-07 16:30 +0200 |
| Subject | [PATCH v5 net-next 09/12] selftests/bpf: add tests for subtraction & negative numbers |
| Message-ID | <ubRcE-10r-43@gated-at.bofh.it> |
| In reply to | #1705573 |
Signed-off-by: Edward Cree <ecree@solarflare.com>
---
tools/testing/selftests/bpf/test_align.c | 104 +++++++++++++++++++++++++++++++
1 file changed, 104 insertions(+)
diff --git a/tools/testing/selftests/bpf/test_align.c b/tools/testing/selftests/bpf/test_align.c
index b081683..8591c89 100644
--- a/tools/testing/selftests/bpf/test_align.c
+++ b/tools/testing/selftests/bpf/test_align.c
@@ -497,6 +497,110 @@ static struct bpf_align_test tests[] = {
{16, "R6=pkt(id=1,off=0,r=0,umin_value=2,umax_value=9223372036854775806,var_off=(0x2; 0x7ffffffffffffffc))"},
}
},
+ {
+ .descr = "variable subtraction",
+ .insns = {
+ /* Create an unknown offset, (4n+2)-aligned */
+ LOAD_UNKNOWN(BPF_REG_6),
+ BPF_MOV64_REG(BPF_REG_7, BPF_REG_6),
+ BPF_ALU64_IMM(BPF_LSH, BPF_REG_6, 2),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_6, 14),
+ /* Create another unknown, (4n)-aligned, and subtract
+ * it from the first one
+ */
+ BPF_ALU64_IMM(BPF_LSH, BPF_REG_7, 2),
+ BPF_ALU64_REG(BPF_SUB, BPF_REG_6, BPF_REG_7),
+ /* Bounds-check the result */
+ BPF_JMP_IMM(BPF_JSGE, BPF_REG_6, 0, 1),
+ BPF_EXIT_INSN(),
+ /* Add it to the packet pointer */
+ BPF_MOV64_REG(BPF_REG_5, BPF_REG_2),
+ BPF_ALU64_REG(BPF_ADD, BPF_REG_5, BPF_REG_6),
+ /* Check bounds and perform a read */
+ BPF_MOV64_REG(BPF_REG_4, BPF_REG_5),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, 4),
+ BPF_JMP_REG(BPF_JGE, BPF_REG_3, BPF_REG_4, 1),
+ BPF_EXIT_INSN(),
+ BPF_LDX_MEM(BPF_W, BPF_REG_6, BPF_REG_5, 0),
+ BPF_EXIT_INSN(),
+ },
+ .prog_type = BPF_PROG_TYPE_SCHED_CLS,
+ .matches = {
+ /* Calculated offset in R6 has unknown value, but known
+ * alignment of 4.
+ */
+ {7, "R2=pkt(id=0,off=0,r=8,imm=0)"},
+ {9, "R6=inv(id=0,umax_value=1020,var_off=(0x0; 0x3fc))"},
+ /* Adding 14 makes R6 be (4n+2) */
+ {10, "R6=inv(id=0,umin_value=14,umax_value=1034,var_off=(0x2; 0x7fc))"},
+ /* New unknown value in R7 is (4n) */
+ {11, "R7=inv(id=0,umax_value=1020,var_off=(0x0; 0x3fc))"},
+ /* Subtracting it from R6 blows our unsigned bounds */
+ {12, "R6=inv(id=0,smin_value=-1006,smax_value=1034,var_off=(0x2; 0xfffffffffffffffc))"},
+ /* Checked s>= 0 */
+ {14, "R6=inv(id=0,umin_value=2,umax_value=1034,var_off=(0x2; 0x7fc))"},
+ /* At the time the word size load is performed from R5,
+ * its total fixed offset is NET_IP_ALIGN + reg->off (0)
+ * which is 2. Then the variable offset is (4n+2), so
+ * the total offset is 4-byte aligned and meets the
+ * load's requirements.
+ */
+ {20, "R5=pkt(id=1,off=0,r=4,umin_value=2,umax_value=1034,var_off=(0x2; 0x7fc))"},
+ },
+ },
+ {
+ .descr = "pointer variable subtraction",
+ .insns = {
+ /* Create an unknown offset, (4n+2)-aligned and bounded
+ * to [14,74]
+ */
+ LOAD_UNKNOWN(BPF_REG_6),
+ BPF_MOV64_REG(BPF_REG_7, BPF_REG_6),
+ BPF_ALU64_IMM(BPF_AND, BPF_REG_6, 0xf),
+ BPF_ALU64_IMM(BPF_LSH, BPF_REG_6, 2),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_6, 14),
+ /* Subtract it from the packet pointer */
+ BPF_MOV64_REG(BPF_REG_5, BPF_REG_2),
+ BPF_ALU64_REG(BPF_SUB, BPF_REG_5, BPF_REG_6),
+ /* Create another unknown, (4n)-aligned and >= 74.
+ * That in fact means >= 76, since 74 % 4 == 2
+ */
+ BPF_ALU64_IMM(BPF_LSH, BPF_REG_7, 2),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_7, 76),
+ /* Add it to the packet pointer */
+ BPF_ALU64_REG(BPF_ADD, BPF_REG_5, BPF_REG_7),
+ /* Check bounds and perform a read */
+ BPF_MOV64_REG(BPF_REG_4, BPF_REG_5),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, 4),
+ BPF_JMP_REG(BPF_JGE, BPF_REG_3, BPF_REG_4, 1),
+ BPF_EXIT_INSN(),
+ BPF_LDX_MEM(BPF_W, BPF_REG_6, BPF_REG_5, 0),
+ BPF_EXIT_INSN(),
+ },
+ .prog_type = BPF_PROG_TYPE_SCHED_CLS,
+ .matches = {
+ /* Calculated offset in R6 has unknown value, but known
+ * alignment of 4.
+ */
+ {7, "R2=pkt(id=0,off=0,r=8,imm=0)"},
+ {10, "R6=inv(id=0,umax_value=60,var_off=(0x0; 0x3c))"},
+ /* Adding 14 makes R6 be (4n+2) */
+ {11, "R6=inv(id=0,umin_value=14,umax_value=74,var_off=(0x2; 0x7c))"},
+ /* Subtracting from packet pointer overflows ubounds */
+ {13, "R5=pkt(id=1,off=0,r=8,umin_value=18446744073709551542,umax_value=18446744073709551602,var_off=(0xffffffffffffff82; 0x7c))"},
+ /* New unknown value in R7 is (4n), >= 76 */
+ {15, "R7=inv(id=0,umin_value=76,umax_value=1096,var_off=(0x0; 0x7fc))"},
+ /* Adding it to packet pointer gives nice bounds again */
+ {16, "R5=pkt(id=2,off=0,r=0,umin_value=2,umax_value=1082,var_off=(0x2; 0x7fc))"},
+ /* At the time the word size load is performed from R5,
+ * its total fixed offset is NET_IP_ALIGN + reg->off (0)
+ * which is 2. Then the variable offset is (4n+2), so
+ * the total offset is 4-byte aligned and meets the
+ * load's requirements.
+ */
+ {20, "R5=pkt(id=2,off=0,r=4,umin_value=2,umax_value=1082,var_off=(0x2; 0x7fc))"},
+ },
+ },
};
static int probe_filter_length(const struct bpf_insn *fp)
[toc] | [prev] | [next] | [standalone]
| From | Edward Cree <ecree@solarflare.com> |
|---|---|
| Date | 2017-08-07 16:40 +0200 |
| Subject | [PATCH v5 net-next 11/12] Documentation: describe the new eBPF verifier value tracking behaviour |
| Message-ID | <ubRmh-148-3@gated-at.bofh.it> |
| In reply to | #1705573 |
Also bring the eBPF documentation up to date in other ways.
Signed-off-by: Edward Cree <ecree@solarflare.com>
---
Documentation/networking/filter.txt | 122 ++++++++++++++++++++++++++++++------
1 file changed, 104 insertions(+), 18 deletions(-)
diff --git a/Documentation/networking/filter.txt b/Documentation/networking/filter.txt
index b69b205..d0fdba7 100644
--- a/Documentation/networking/filter.txt
+++ b/Documentation/networking/filter.txt
@@ -793,7 +793,7 @@ Some core changes of the new internal format:
bpf_exit
After the call the registers R1-R5 contain junk values and cannot be read.
- In the future an eBPF verifier can be used to validate internal BPF programs.
+ An in-kernel eBPF verifier is used to validate internal BPF programs.
Also in the new design, eBPF is limited to 4096 insns, which means that any
program will terminate quickly and will only call a fixed number of kernel
@@ -1017,7 +1017,7 @@ At the start of the program the register R1 contains a pointer to context
and has type PTR_TO_CTX.
If verifier sees an insn that does R2=R1, then R2 has now type
PTR_TO_CTX as well and can be used on the right hand side of expression.
-If R1=PTR_TO_CTX and insn is R2=R1+R1, then R2=UNKNOWN_VALUE,
+If R1=PTR_TO_CTX and insn is R2=R1+R1, then R2=SCALAR_VALUE,
since addition of two valid pointers makes invalid pointer.
(In 'secure' mode verifier will reject any type of pointer arithmetic to make
sure that kernel addresses don't leak to unprivileged users)
@@ -1039,7 +1039,7 @@ is a correct program. If there was R1 instead of R6, it would have
been rejected.
load/store instructions are allowed only with registers of valid types, which
-are PTR_TO_CTX, PTR_TO_MAP, FRAME_PTR. They are bounds and alignment checked.
+are PTR_TO_CTX, PTR_TO_MAP, PTR_TO_STACK. They are bounds and alignment checked.
For example:
bpf_mov R1 = 1
bpf_mov R2 = 2
@@ -1058,7 +1058,7 @@ intends to load a word from address R6 + 8 and store it into R0
If R6=PTR_TO_CTX, via is_valid_access() callback the verifier will know
that offset 8 of size 4 bytes can be accessed for reading, otherwise
the verifier will reject the program.
-If R6=FRAME_PTR, then access should be aligned and be within
+If R6=PTR_TO_STACK, then access should be aligned and be within
stack bounds, which are [-MAX_BPF_STACK, 0). In this example offset is 8,
so it will fail verification, since it's out of bounds.
@@ -1069,7 +1069,7 @@ For example:
bpf_ld R0 = *(u32 *)(R10 - 4)
bpf_exit
is invalid program.
-Though R10 is correct read-only register and has type FRAME_PTR
+Though R10 is correct read-only register and has type PTR_TO_STACK
and R10 - 4 is within stack bounds, there were no stores into that location.
Pointer register spill/fill is tracked as well, since four (R6-R9)
@@ -1094,6 +1094,71 @@ all use cases.
See details of eBPF verifier in kernel/bpf/verifier.c
+Register value tracking
+-----------------------
+In order to determine the safety of an eBPF program, the verifier must track
+the range of possible values in each register and also in each stack slot.
+This is done with 'struct bpf_reg_state', defined in include/linux/
+bpf_verifier.h, which unifies tracking of scalar and pointer values. Each
+register state has a type, which is either NOT_INIT (the register has not been
+written to), SCALAR_VALUE (some value which is not usable as a pointer), or a
+pointer type. The types of pointers describe their base, as follows:
+ PTR_TO_CTX Pointer to bpf_context.
+ CONST_PTR_TO_MAP Pointer to struct bpf_map. "Const" because arithmetic
+ on these pointers is forbidden.
+ PTR_TO_MAP_VALUE Pointer to the value stored in a map element.
+ PTR_TO_MAP_VALUE_OR_NULL
+ Either a pointer to a map value, or NULL; map accesses
+ (see section 'eBPF maps', below) return this type,
+ which becomes a PTR_TO_MAP_VALUE when checked != NULL.
+ Arithmetic on these pointers is forbidden.
+ PTR_TO_STACK Frame pointer.
+ PTR_TO_PACKET skb->data.
+ PTR_TO_PACKET_END skb->data + headlen; arithmetic forbidden.
+However, a pointer may be offset from this base (as a result of pointer
+arithmetic), and this is tracked in two parts: the 'fixed offset' and 'variable
+offset'. The former is used when an exactly-known value (e.g. an immediate
+operand) is added to a pointer, while the latter is used for values which are
+not exactly known. The variable offset is also used in SCALAR_VALUEs, to track
+the range of possible values in the register.
+The verifier's knowledge about the variable offset consists of:
+* minimum and maximum values as unsigned
+* minimum and maximum values as signed
+* knowledge of the values of individual bits, in the form of a 'tnum': a u64
+'mask' and a u64 'value'. 1s in the mask represent bits whose value is unknown;
+1s in the value represent bits known to be 1. Bits known to be 0 have 0 in both
+mask and value; no bit should ever be 1 in both. For example, if a byte is read
+into a register from memory, the register's top 56 bits are known zero, while
+the low 8 are unknown - which is represented as the tnum (0x0; 0xff). If we
+then OR this with 0x40, we get (0x40; 0xcf), then if we add 1 we get (0x0;
+0x1ff), because of potential carries.
+Besides arithmetic, the register state can also be updated by conditional
+branches. For instance, if a SCALAR_VALUE is compared > 8, in the 'true' branch
+it will have a umin_value (unsigned minimum value) of 9, whereas in the 'false'
+branch it will have a umax_value of 8. A signed compare (with BPF_JSGT or
+BPF_JSGE) would instead update the signed minimum/maximum values. Information
+from the signed and unsigned bounds can be combined; for instance if a value is
+first tested < 8 and then tested s> 4, the verifier will conclude that the value
+is also > 4 and s< 8, since the bounds prevent crossing the sign boundary.
+PTR_TO_PACKETs with a variable offset part have an 'id', which is common to all
+pointers sharing that same variable offset. This is important for packet range
+checks: after adding some variable to a packet pointer, if you then copy it to
+another register and (say) add a constant 4, both registers will share the same
+'id' but one will have a fixed offset of +4. Then if it is bounds-checked and
+found to be less than a PTR_TO_PACKET_END, the other register is now known to
+have a safe range of at least 4 bytes. See 'Direct packet access', below, for
+more on PTR_TO_PACKET ranges.
+The 'id' field is also used on PTR_TO_MAP_VALUE_OR_NULL, common to all copies of
+the pointer returned from a map lookup. This means that when one copy is
+checked and found to be non-NULL, all copies can become PTR_TO_MAP_VALUEs.
+As well as range-checking, the tracked information is also used for enforcing
+alignment of pointer accesses. For instance, on most systems the packet pointer
+is 2 bytes after a 4-byte alignment. If a program adds 14 bytes to that to jump
+over the Ethernet header, then reads IHL and addes (IHL * 4), the resulting
+pointer will have a variable offset known to be 4n+2 for some n, so adding the 2
+bytes (NET_IP_ALIGN) gives a 4-byte alignment and so word-sized accesses through
+that pointer are safe.
+
Direct packet access
--------------------
In cls_bpf and act_bpf programs the verifier allows direct access to the packet
@@ -1121,7 +1186,7 @@ it now points to 'skb->data + 14' and accessible range is [R5, R5 + 14 - 14)
which is zero bytes.
More complex packet access may look like:
- R0=imm1 R1=ctx R3=pkt(id=0,off=0,r=14) R4=pkt_end R5=pkt(id=0,off=14,r=14) R10=fp
+ R0=inv1 R1=ctx R3=pkt(id=0,off=0,r=14) R4=pkt_end R5=pkt(id=0,off=14,r=14) R10=fp
6: r0 = *(u8 *)(r3 +7) /* load 7th byte from the packet */
7: r4 = *(u8 *)(r3 +12)
8: r4 *= 14
@@ -1135,26 +1200,31 @@ More complex packet access may look like:
16: r2 += 8
17: r1 = *(u32 *)(r1 +80) /* load skb->data_end */
18: if r2 > r1 goto pc+2
- R0=inv56 R1=pkt_end R2=pkt(id=2,off=8,r=8) R3=pkt(id=2,off=0,r=8) R4=inv52 R5=pkt(id=0,off=14,r=14) R10=fp
+ R0=inv(id=0,umax_value=255,var_off=(0x0; 0xff)) R1=pkt_end R2=pkt(id=2,off=8,r=8) R3=pkt(id=2,off=0,r=8) R4=inv(id=0,umax_value=3570,var_off=(0x0; 0xfffe)) R5=pkt(id=0,off=14,r=14) R10=fp
19: r1 = *(u8 *)(r3 +4)
The state of the register R3 is R3=pkt(id=2,off=0,r=8)
id=2 means that two 'r3 += rX' instructions were seen, so r3 points to some
offset within a packet and since the program author did
'if (r3 + 8 > r1) goto err' at insn #18, the safe range is [R3, R3 + 8).
-The verifier only allows 'add' operation on packet registers. Any other
-operation will set the register state to 'unknown_value' and it won't be
+The verifier only allows 'add'/'sub' operations on packet registers. Any other
+operation will set the register state to 'SCALAR_VALUE' and it won't be
available for direct packet access.
Operation 'r3 += rX' may overflow and become less than original skb->data,
-therefore the verifier has to prevent that. So it tracks the number of
-upper zero bits in all 'uknown_value' registers, so when it sees
-'r3 += rX' instruction and rX is more than 16-bit value, it will error as:
-"cannot add integer value with N upper zero bits to ptr_to_packet"
+therefore the verifier has to prevent that. So when it sees 'r3 += rX'
+instruction and rX is more than 16-bit value, any subsequent bounds-check of r3
+against skb->data_end will not give us 'range' information, so attempts to read
+through the pointer will give "invalid access to packet" error.
Ex. after insn 'r4 = *(u8 *)(r3 +12)' (insn #7 above) the state of r4 is
-R4=inv56 which means that upper 56 bits on the register are guaranteed
-to be zero. After insn 'r4 *= 14' the state becomes R4=inv52, since
-multiplying 8-bit value by constant 14 will keep upper 52 bits as zero.
-Similarly 'r2 >>= 48' will make R2=inv48, since the shift is not sign
-extending. This logic is implemented in evaluate_reg_alu() function.
+R4=inv(id=0,umax_value=255,var_off=(0x0; 0xff)) which means that upper 56 bits
+of the register are guaranteed to be zero, and nothing is known about the lower
+8 bits. After insn 'r4 *= 14' the state becomes
+R4=inv(id=0,umax_value=3570,var_off=(0x0; 0xfffe)), since multiplying an 8-bit
+value by constant 14 will keep upper 52 bits as zero, also the least significant
+bit will be zero as 14 is even. Similarly 'r2 >>= 48' will make
+R2=inv(id=0,umax_value=65535,var_off=(0x0; 0xffff)), since the shift is not sign
+extending. This logic is implemented in adjust_reg_min_max_vals() function,
+which calls adjust_ptr_min_max_vals() for adding pointer to scalar (or vice
+versa) and adjust_scalar_min_max_vals() for operations on two scalars.
The end result is that bpf program author can access packet directly
using normal C code as:
@@ -1214,6 +1284,22 @@ The map is defined by:
. key size in bytes
. value size in bytes
+Pruning
+-------
+The verifier does not actually walk all possible paths through the program. For
+each new branch to analyse, the verifier looks at all the states it's previously
+been in when at this instruction. If any of them contain the current state as a
+subset, the branch is 'pruned' - that is, the fact that the previous state was
+accepted implies the current state would be as well. For instance, if in the
+previous state, r1 held a packet-pointer, and in the current state, r1 holds a
+packet-pointer with a range as long or longer and at least as strict an
+alignment, then r1 is safe. Similarly, if r2 was NOT_INIT before then it can't
+have been used by any path from that point, so any value in r2 (including
+another NOT_INIT) is safe. The implementation is in the function regsafe().
+Pruning considers not only the registers but also the stack (and any spilled
+registers it may hold). They must all be safe for the branch to be pruned.
+This is implemented in states_equal().
+
Understanding eBPF verifier messages
------------------------------------
[toc] | [prev] | [next] | [standalone]
| From | Edward Cree <ecree@solarflare.com> |
|---|---|
| Date | 2017-08-07 16:40 +0200 |
| Subject | [PATCH v5 net-next 12/12] bpf/verifier: increase complexity limit to 128k |
| Message-ID | <ubRmj-148-23@gated-at.bofh.it> |
| In reply to | #1705573 |
The more detailed value tracking can reduce the effectiveness of pruning
for some programs. So, to avoid rejecting previously valid programs, up
the limit to 128kinsns. Hopefully we will be able to bring this back
down later by improving pruning performance.
Signed-off-by: Edward Cree <ecree@solarflare.com>
---
kernel/bpf/verifier.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 08a6fa0..8160a81 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -140,7 +140,7 @@ struct bpf_verifier_stack_elem {
struct bpf_verifier_stack_elem *next;
};
-#define BPF_COMPLEXITY_LIMIT_INSNS 98304
+#define BPF_COMPLEXITY_LIMIT_INSNS 131072
#define BPF_COMPLEXITY_LIMIT_STACK 1024
#define BPF_MAP_PTR_POISON ((void *)0xeB9F + POISON_POINTER_DELTA)
[toc] | [prev] | [next] | [standalone]
| From | Edward Cree <ecree@solarflare.com> |
|---|---|
| Date | 2017-08-07 16:40 +0200 |
| Subject | [PATCH v5 net-next 10/12] selftests/bpf: variable offset negative tests |
| Message-ID | <ubRmj-148-25@gated-at.bofh.it> |
| In reply to | #1705573 |
Variable ctx accesses and stack accesses aren't allowed, because we can't
determine what type of value will be read.
Signed-off-by: Edward Cree <ecree@solarflare.com>
---
tools/testing/selftests/bpf/test_verifier.c | 41 +++++++++++++++++++++++++++++
1 file changed, 41 insertions(+)
diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c
index 876b878..65aa562 100644
--- a/tools/testing/selftests/bpf/test_verifier.c
+++ b/tools/testing/selftests/bpf/test_verifier.c
@@ -5980,6 +5980,47 @@ static struct bpf_test tests[] = {
.errstr = "R0 min value is negative, either use unsigned index or do a if (index >=0) check.",
.result = REJECT,
},
+ {
+ "variable-offset ctx access",
+ .insns = {
+ /* Get an unknown value */
+ BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, 0),
+ /* Make it small and 4-byte aligned */
+ BPF_ALU64_IMM(BPF_AND, BPF_REG_2, 4),
+ /* add it to skb. We now have either &skb->len or
+ * &skb->pkt_type, but we don't know which
+ */
+ BPF_ALU64_REG(BPF_ADD, BPF_REG_1, BPF_REG_2),
+ /* dereference it */
+ BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1, 0),
+ BPF_EXIT_INSN(),
+ },
+ .errstr = "variable ctx access var_off=(0x0; 0x4)",
+ .result = REJECT,
+ .prog_type = BPF_PROG_TYPE_LWT_IN,
+ },
+ {
+ "variable-offset stack access",
+ .insns = {
+ /* Fill the top 8 bytes of the stack */
+ BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
+ /* Get an unknown value */
+ BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, 0),
+ /* Make it small and 4-byte aligned */
+ BPF_ALU64_IMM(BPF_AND, BPF_REG_2, 4),
+ BPF_ALU64_IMM(BPF_SUB, BPF_REG_2, 8),
+ /* add it to fp. We now have either fp-4 or fp-8, but
+ * we don't know which
+ */
+ BPF_ALU64_REG(BPF_ADD, BPF_REG_2, BPF_REG_10),
+ /* dereference it */
+ BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_2, 0),
+ BPF_EXIT_INSN(),
+ },
+ .errstr = "variable stack access var_off=(0xfffffffffffffff8; 0x4)",
+ .result = REJECT,
+ .prog_type = BPF_PROG_TYPE_LWT_IN,
+ },
};
static int probe_filter_length(const struct bpf_insn *fp)
[toc] | [prev] | [next] | [standalone]
| From | Daniel Borkmann <daniel@iogearbox.net> |
|---|---|
| Date | 2017-08-08 02:50 +0200 |
| Message-ID | <uc0SB-87I-3@gated-at.bofh.it> |
| In reply to | #1705573 |
On 08/07/2017 04:21 PM, Edward Cree wrote: > This series simplifies alignment tracking, generalises bounds tracking and > fixes some bounds-tracking bugs in the BPF verifier. Pointer arithmetic on > packet pointers, stack pointers, map value pointers and context pointers has > been unified, and bounds on these pointers are only checked when the pointer > is dereferenced. > Operations on pointers which destroy all relation to the original pointer > (such as multiplies and shifts) are disallowed if !env->allow_ptr_leaks, > otherwise they convert the pointer to an unknown scalar and feed it to the > normal scalar arithmetic handling. > Pointer types have been unified with the corresponding adjusted-pointer types > where those existed (e.g. PTR_TO_MAP_VALUE[_ADJ] or FRAME_PTR vs > PTR_TO_STACK); similarly, CONST_IMM and UNKNOWN_VALUE have been unified into > SCALAR_VALUE. > Pointer types (except CONST_PTR_TO_MAP, PTR_TO_MAP_VALUE_OR_NULL and > PTR_TO_PACKET_END, which do not allow arithmetic) have a 'fixed offset' and > a 'variable offset'; the former is used when e.g. adding an immediate or a > known-constant register, as long as it does not overflow. Otherwise the > latter is used, and any operation creating a new variable offset creates a > new 'id' (and, for PTR_TO_PACKET, clears the 'range'). > SCALAR_VALUEs use the 'variable offset' fields to track the range of possible > values; the 'fixed offset' should never be set on a scalar. Been testing and reviewing the series over the last several days, looks reasonable to me as far as I can tell. Thanks for all the hard work on unifying this, Edward! Acked-by: Daniel Borkmann <daniel@iogearbox.net>
[toc] | [prev] | [next] | [standalone]
| From | David Miller <davem@davemloft.net> |
|---|---|
| Date | 2017-08-09 03:00 +0200 |
| Subject | Re: [PATCH v5 net-next 00/12] bpf: rewrite value tracking in verifier |
| Message-ID | <ucnvQ-7US-1@gated-at.bofh.it> |
| In reply to | #1705932 |
From: Daniel Borkmann <daniel@iogearbox.net> Date: Tue, 08 Aug 2017 02:46:16 +0200 > On 08/07/2017 04:21 PM, Edward Cree wrote: >> This series simplifies alignment tracking, generalises bounds tracking >> and >> fixes some bounds-tracking bugs in the BPF verifier. Pointer >> arithmetic on >> packet pointers, stack pointers, map value pointers and context >> pointers has >> been unified, and bounds on these pointers are only checked when the >> pointer >> is dereferenced. >> Operations on pointers which destroy all relation to the original >> pointer >> (such as multiplies and shifts) are disallowed if >> !env->allow_ptr_leaks, >> otherwise they convert the pointer to an unknown scalar and feed it to >> the >> normal scalar arithmetic handling. >> Pointer types have been unified with the corresponding >> adjusted-pointer types >> where those existed (e.g. PTR_TO_MAP_VALUE[_ADJ] or FRAME_PTR vs >> PTR_TO_STACK); similarly, CONST_IMM and UNKNOWN_VALUE have been >> unified into >> SCALAR_VALUE. >> Pointer types (except CONST_PTR_TO_MAP, PTR_TO_MAP_VALUE_OR_NULL and >> PTR_TO_PACKET_END, which do not allow arithmetic) have a 'fixed >> offset' and >> a 'variable offset'; the former is used when e.g. adding an immediate >> or a >> known-constant register, as long as it does not overflow. Otherwise >> the >> latter is used, and any operation creating a new variable offset >> creates a >> new 'id' (and, for PTR_TO_PACKET, clears the 'range'). >> SCALAR_VALUEs use the 'variable offset' fields to track the range of >> possible >> values; the 'fixed offset' should never be set on a scalar. > > Been testing and reviewing the series over the last several days, > looks > reasonable to me as far as I can tell. Thanks for all the hard work on > unifying this, Edward! > > Acked-by: Daniel Borkmann <daniel@iogearbox.net> Series applied, thanks everyone!
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