Test dynptr convenience helpers in the following way:
1) bpf_dynptr_data_rdonly
* "data_slice_rdonly" tests that writes into read-only slices
are rejected.
* "skb_invalid_data_slice_rdonly{1,2}" tests that read-only
slices for skb-type dynptrs get invalidated whenever packet data
may change.
2) bpf_dynptr_trim and bpf_dynptr_advance
* "test_advance_trim" tests that dynptr offset and size get adjusted
correctly.
* "test_advance_trim_err" tests that advances beyond dynptr size and
trims larger than dynptr size are rejected.
* "test_zero_size_dynptr" tests that a zero-size dynptr (after
advancing or trimming) can only read and write 0 bytes.
3) bpf_dynptr_is_null
* "dynptr_is_null_invalid" tests that only initialized dynptrs can
be passed in.
* "test_dynptr_is_null" tests that null dynptrs return true and
non-null dynptrs return false.
4) bpf_dynptr_is_rdonly
* "dynptr_is_rdonly_invalid" tests that only initialized dynptrs can
be passed in.
* "test_dynptr_is_rdonly" tests that rdonly dynptrs return true and
non-rdonly or invalid dynptrs return false.
5) bpf_dynptr_get_size
* "dynptr_get_size_invalid" tests that only initialized dynptrs can
be passed in.
* Additional functionality is tested as a by-product in
"test_advance_trim"
6) bpf_dynptr_get_offset
* "dynptr_get_offset_invalid" tests that only initialized dynptrs can
be passed in.
* Additional functionality is tested as a by-product in
"test_advance_trim"
7) bpf_dynptr_clone
* "clone_invalidate_{1..6}" tests that invalidating a dynptr
invalidates all instances and invalidating a dynptr's data slices
invalidates all data slices for all instances.
* "clone_skb_packet_data" tests that data slices of skb dynptr instances
are invalidated when packet data changes.
* "clone_xdp_packet_data" tests that data slices of xdp dynptr instances
are invalidated when packet data changes.
* "clone_invalid1" tests that only initialized dynptrs can be
cloned.
* "clone_invalid2" tests that only uninitialized dynptrs can be
a clone.
* "test_dynptr_clone" tests that the views from the same dynptr instances
are independent (advancing or trimming a dynptr doesn't affect other
instances), and that a clone will return a dynptr with the same
type, offset, size, and rd-only property.
8) bpf_dynptr_iterator
* "iterator_invalid1" tests that any dynptr requiring a release
that gets acquired in an iterator callback must also be released
within the callback
* "iterator_invalid2" tests that bpf_dynptr_iterator can't be called
on an uninitialized dynptr
* "iterator_invalid3" tests that an already-initialized dynptr can't
be initialized again in the iterator callback function
* "iterator_invalid4" tests that the dynptr that's iterating
can't be released in the callback function
* "iterator_invalid5" tests that the dynptr can't be passed as a
callback ctx and released within the callback
* "test_dynptr_iterator" tests basic functionality of the iterator
* "iterator_parse_strings" tests parsing strings as values
Signed-off-by: Joanne Koong <joannelkoong@xxxxxxxxx>
---
.../testing/selftests/bpf/prog_tests/dynptr.c | 30 +
.../testing/selftests/bpf/progs/dynptr_fail.c | 462 +++++++++++++++
.../selftests/bpf/progs/dynptr_success.c | 551 +++++++++++++++++-
3 files changed, 1041 insertions(+), 2 deletions(-)
diff --git a/tools/testing/selftests/bpf/prog_tests/dynptr.c b/tools/testing/selftests/bpf/prog_tests/dynptr.c
index f3bdec4a595c..de084ba980a9 100644
--- a/tools/testing/selftests/bpf/prog_tests/dynptr.c
+++ b/tools/testing/selftests/bpf/prog_tests/dynptr.c
@@ -53,15 +53,45 @@ static struct {
"Unsupported reg type fp for bpf_dynptr_from_mem data"},
{"skb_invalid_data_slice1", "invalid mem access 'scalar'"},
{"skb_invalid_data_slice2", "invalid mem access 'scalar'"},
+ {"skb_invalid_data_slice_rdonly1", "invalid mem access 'scalar'"},
+ {"skb_invalid_data_slice_rdonly2", "invalid mem access 'scalar'"},
{"xdp_invalid_data_slice", "invalid mem access 'scalar'"},
{"skb_invalid_ctx", "unknown func bpf_dynptr_from_skb"},
{"xdp_invalid_ctx", "unknown func bpf_dynptr_from_xdp"},
+ {"data_slice_rdonly", "cannot write into rdonly_mem"},
+ {"dynptr_is_null_invalid", "Expected an initialized dynptr as arg #1"},
+ {"dynptr_is_rdonly_invalid", "Expected an initialized dynptr as arg #1"},
+ {"dynptr_get_size_invalid", "Expected an initialized dynptr as arg #1"},
+ {"dynptr_get_offset_invalid", "Expected an initialized dynptr as arg #1"},
+ {"clone_invalid1", "Expected an initialized dynptr as arg #1"},
+ {"clone_invalid2", "Dynptr has to be an uninitialized dynptr"},
+ {"clone_invalidate1", "Expected an initialized dynptr"},
+ {"clone_invalidate2", "Expected an initialized dynptr"},
+ {"clone_invalidate3", "Expected an initialized dynptr"},
+ {"clone_invalidate4", "invalid mem access 'scalar'"},
+ {"clone_invalidate5", "invalid mem access 'scalar'"},
+ {"clone_invalidate6", "invalid mem access 'scalar'"},
+ {"clone_skb_packet_data", "invalid mem access 'scalar'"},
+ {"clone_xdp_packet_data", "invalid mem access 'scalar'"},
+ {"iterator_invalid1", "Unreleased reference id=1"},
+ {"iterator_invalid2", "Expected an initialized dynptr as arg #1"},
+ {"iterator_invalid3", "Dynptr has to be an uninitialized dynptr"},
+ {"iterator_invalid4", "Unreleased reference"},
+ {"iterator_invalid5", "Unreleased reference"},
/* these tests should be run and should succeed */
{"test_read_write", NULL, SETUP_SYSCALL_SLEEP},
{"test_data_slice", NULL, SETUP_SYSCALL_SLEEP},
{"test_ringbuf", NULL, SETUP_SYSCALL_SLEEP},
{"test_skb_readonly", NULL, SETUP_SKB_PROG},
+ {"test_advance_trim", NULL, SETUP_SYSCALL_SLEEP},
+ {"test_advance_trim_err", NULL, SETUP_SYSCALL_SLEEP},
+ {"test_zero_size_dynptr", NULL, SETUP_SYSCALL_SLEEP},
+ {"test_dynptr_is_null", NULL, SETUP_SYSCALL_SLEEP},
+ {"test_dynptr_is_rdonly", NULL, SETUP_SKB_PROG},
+ {"test_dynptr_clone", NULL, SETUP_SKB_PROG},
+ {"test_dynptr_iterator", NULL, SETUP_SKB_PROG},
+ {"iterator_parse_strings", NULL, SETUP_SYSCALL_SLEEP},
};
static void verify_fail(const char *prog_name, const char *expected_err_msg)
diff --git a/tools/testing/selftests/bpf/progs/dynptr_fail.c b/tools/testing/selftests/bpf/progs/dynptr_fail.c
index 2da6703d0caf..5a63389613c7 100644
--- a/tools/testing/selftests/bpf/progs/dynptr_fail.c
+++ b/tools/testing/selftests/bpf/progs/dynptr_fail.c
@@ -668,6 +668,51 @@ int skb_invalid_data_slice2(struct __sk_buff *skb)
return SK_PASS;
}
+/* The read-only data slice is invalidated whenever a helper changes packet data */
+SEC("?tc")
+int skb_invalid_data_slice_rdonly1(struct __sk_buff *skb)
+{
+ struct bpf_dynptr ptr;
+ struct ethhdr *hdr;
+
+ bpf_dynptr_from_skb(skb, 0, &ptr);
+ hdr = bpf_dynptr_data_rdonly(&ptr, 0, sizeof(*hdr));
+
+ if (!hdr)
+ return SK_DROP;
+
+ val = hdr->h_proto;
+
+ if (bpf_skb_pull_data(skb, skb->len))
+ return SK_DROP;
+
+ /* this should fail */
+ val = hdr->h_proto;
+
+ return SK_PASS;
+}
+
+/* The read-only data slice is invalidated whenever bpf_dynptr_write() is called */
+SEC("?tc")
+int skb_invalid_data_slice_rdonly2(struct __sk_buff *skb)
+{
+ char write_data[64] = "hello there, world!!";
+ struct bpf_dynptr ptr;
+ struct ethhdr *hdr;
+
+ bpf_dynptr_from_skb(skb, 0, &ptr);
+ hdr = bpf_dynptr_data_rdonly(&ptr, 0, sizeof(*hdr));
+ if (!hdr)
+ return SK_DROP;
+
+ bpf_dynptr_write(&ptr, 0, write_data, sizeof(write_data), 0);
+
+ /* this should fail */
+ val = hdr->h_proto;
+
+ return SK_PASS;
+}
+
/* The data slice is invalidated whenever a helper changes packet data */
SEC("?xdp")
int xdp_invalid_data_slice(struct xdp_md *xdp)
@@ -714,3 +759,420 @@ int xdp_invalid_ctx(void *ctx)
return 0;
}
+
+/* Writing into a read-only data slice is not permitted */
+SEC("?raw_tp")
+int data_slice_rdonly(void *ctx)
+{
+ struct bpf_dynptr ptr;
+ __u64 *data;
+
+ bpf_ringbuf_reserve_dynptr(&ringbuf, 64, 0, &ptr);
+
+ data = bpf_dynptr_data_rdonly(&ptr, 0, 64);
+ if (data)
+ /* this should fail */
+ *data = 123;
+
+ bpf_ringbuf_submit_dynptr(&ptr, 0);
+
+ return 0;
+}
+
+/* dynptr_is_null can only be called on initialized dynptrs */
+SEC("?raw_tp")
+int dynptr_is_null_invalid(void *ctx)
+{
+ struct bpf_dynptr ptr;
+
+ /* this should fail */
+ bpf_dynptr_is_null(&ptr);
+
+ return 0;
+}
+
+/* dynptr_is_rdonly can only be called on initialized dynptrs */
+SEC("?raw_tp")
+int dynptr_is_rdonly_invalid(void *ctx)
+{
+ struct bpf_dynptr ptr;
+
+ /* this should fail */
+ bpf_dynptr_is_rdonly(&ptr);
+
+ return 0;
+}
+
+/* dynptr_get_size can only be called on initialized dynptrs */
+SEC("?raw_tp")
+int dynptr_get_size_invalid(void *ctx)
+{
+ struct bpf_dynptr ptr;
+
+ /* this should fail */
+ bpf_dynptr_get_size(&ptr);
+
+ return 0;
+}
+
+/* dynptr_get_offset can only be called on initialized dynptrs */
+SEC("?raw_tp")
+int dynptr_get_offset_invalid(void *ctx)
+{
+ struct bpf_dynptr ptr;
+
+ /* this should fail */
+ bpf_dynptr_get_offset(&ptr);
+
+ return 0;
+}
+
+/* Only initialized dynptrs can be cloned */
+SEC("?raw_tp")
+int clone_invalid1(void *ctx)
+{
+ struct bpf_dynptr ptr1;
+ struct bpf_dynptr ptr2;
+
+ /* this should fail */
+ bpf_dynptr_clone(&ptr1, &ptr2);
+
+ return 0;
+}
+
+/* Only uninitialized dynptrs can be clones */
+SEC("?xdp")
+int clone_invalid2(struct xdp_md *xdp)
+{
+ struct bpf_dynptr ptr1;
+ struct bpf_dynptr clone;
+
+ bpf_dynptr_from_xdp(xdp, 0, &ptr1);
+
+ bpf_ringbuf_reserve_dynptr(&ringbuf, 64, 0, &clone);
+
+ /* this should fail */
+ bpf_dynptr_clone(&ptr1, &clone);
+
+ bpf_ringbuf_submit_dynptr(&clone, 0);
+
+ return 0;
+}
+
+/* Invalidating a dynptr should invalidate its clones */
+SEC("?raw_tp")
+int clone_invalidate1(void *ctx)
+{
+ struct bpf_dynptr clone;
+ struct bpf_dynptr ptr;
+ char read_data[64];
+
+ bpf_ringbuf_reserve_dynptr(&ringbuf, val, 0, &ptr);
+
+ bpf_dynptr_clone(&ptr, &clone);
+
+ bpf_ringbuf_submit_dynptr(&ptr, 0);
+
+ /* this should fail */
+ bpf_dynptr_read(read_data, sizeof(read_data), &clone, 0, 0);
+
+ return 0;
+}
+
+/* Invalidating a dynptr should invalidate its parent */
+SEC("?raw_tp")
+int clone_invalidate2(void *ctx)
+{
+ struct bpf_dynptr ptr;
+ struct bpf_dynptr clone;
+ char read_data[64];
+
+ bpf_ringbuf_reserve_dynptr(&ringbuf, val, 0, &ptr);
+
+ bpf_dynptr_clone(&ptr, &clone);
+
+ bpf_ringbuf_submit_dynptr(&clone, 0);
+
+ /* this should fail */
+ bpf_dynptr_read(read_data, sizeof(read_data), &ptr, 0, 0);
+
+ return 0;
+}
+
+/* Invalidating a dynptr should invalidate its siblings */
+SEC("?raw_tp")
+int clone_invalidate3(void *ctx)
+{
+ struct bpf_dynptr ptr;
+ struct bpf_dynptr clone1;
+ struct bpf_dynptr clone2;
+ char read_data[64];
+
+ bpf_ringbuf_reserve_dynptr(&ringbuf, val, 0, &ptr);
+
+ bpf_dynptr_clone(&ptr, &clone1);
+
+ bpf_dynptr_clone(&ptr, &clone2);
+
+ bpf_ringbuf_submit_dynptr(&clone2, 0);
+
+ /* this should fail */
+ bpf_dynptr_read(read_data, sizeof(read_data), &clone1, 0, 0);
+
+ return 0;
+}
+
+/* Invalidating a dynptr should invalidate any data slices
+ * of its clones
+ */
+SEC("?raw_tp")
+int clone_invalidate4(void *ctx)
+{
+ struct bpf_dynptr ptr;
+ struct bpf_dynptr clone;
+ int *data;
+
+ bpf_ringbuf_reserve_dynptr(&ringbuf, val, 0, &ptr);
+
+ bpf_dynptr_clone(&ptr, &clone);
+ data = bpf_dynptr_data(&clone, 0, sizeof(val));
+ if (!data)
+ return 0;
+
+ bpf_ringbuf_submit_dynptr(&ptr, 0);
+
+ /* this should fail */
+ *data = 123;
+
+ return 0;
+}
+
+/* Invalidating a dynptr should invalidate any data slices
+ * of its parent
+ */
+SEC("?raw_tp")
+int clone_invalidate5(void *ctx)
+{
+ struct bpf_dynptr ptr;
+ struct bpf_dynptr clone;
+ int *data;
+
+ bpf_ringbuf_reserve_dynptr(&ringbuf, val, 0, &ptr);
+ data = bpf_dynptr_data(&ptr, 0, sizeof(val));
+ if (!data)
+ return 0;
+
+ bpf_dynptr_clone(&ptr, &clone);
+
+ bpf_ringbuf_submit_dynptr(&clone, 0);
+
+ /* this should fail */
+ *data = 123;
+
+ return 0;
+}
+
+/* Invalidating a dynptr should invalidate any data slices
+ * of its sibling
+ */
+SEC("?raw_tp")
+int clone_invalidate6(void *ctx)
+{
+ struct bpf_dynptr ptr;
+ struct bpf_dynptr clone1;
+ struct bpf_dynptr clone2;
+ int *data;
+
+ bpf_ringbuf_reserve_dynptr(&ringbuf, val, 0, &ptr);
+
+ bpf_dynptr_clone(&ptr, &clone1);
+
+ bpf_dynptr_clone(&ptr, &clone2);
+
+ data = bpf_dynptr_data(&clone1, 0, sizeof(val));
+ if (!data)
+ return 0;
+
+ bpf_ringbuf_submit_dynptr(&clone2, 0);
+
+ /* this should fail */
+ *data = 123;
+
+ return 0;
+}
+
+/* A skb clone's data slices should be invalid anytime packet data changes */
+SEC("?tc")
+int clone_skb_packet_data(struct __sk_buff *skb)
+{
+ struct bpf_dynptr ptr;
+ struct bpf_dynptr clone;
+ __u32 *data;
+
+ bpf_dynptr_from_skb(skb, 0, &ptr);
+
+ bpf_dynptr_clone(&ptr, &clone);
+ data = bpf_dynptr_data(&clone, 0, sizeof(*data));
+ if (!data)
+ return XDP_DROP;
+
+ if (bpf_skb_pull_data(skb, skb->len))
+ return SK_DROP;
+
+ /* this should fail */
+ *data = 123;
+
+ return 0;
+}
+
+/* A xdp clone's data slices should be invalid anytime packet data changes */
+SEC("?xdp")
+int clone_xdp_packet_data(struct xdp_md *xdp)
+{
+ struct bpf_dynptr ptr;
+ struct bpf_dynptr clone;
+ struct ethhdr *hdr;
+ __u32 *data;
+
+ bpf_dynptr_from_xdp(xdp, 0, &ptr);
+
+ bpf_dynptr_clone(&ptr, &clone);
+ data = bpf_dynptr_data(&clone, 0, sizeof(*data));
+ if (!data)
+ return XDP_DROP;
+
+ if (bpf_xdp_adjust_head(xdp, 0 - (int)sizeof(*hdr)))
+ return XDP_DROP;
+
+ /* this should fail */
+ *data = 123;
+
+ return 0;
+}
+
+static int iterator_callback1(struct bpf_dynptr *ptr, void *ctx)
+{
+ struct bpf_dynptr local_ptr;
+
+ bpf_ringbuf_reserve_dynptr(&ringbuf, val, 0, &local_ptr);
+
+ /* missing a call to bpf_ringbuf_discard/submit_dynptr */
+
+ return 0;
+}
+
+/* If a dynptr requiring a release is initialized within the iterator callback
+ * function, then it must also be released within that function
+ */
+SEC("?xdp")
+int iterator_invalid1(struct xdp_md *xdp)
+{
+ struct bpf_dynptr ptr;
+
+ bpf_dynptr_from_xdp(xdp, 0, &ptr);
+
+ bpf_dynptr_iterator(&ptr, iterator_callback1, NULL, 0);
+
+ return 0;
+}
+
+/* bpf_dynptr_iterator can't be called on an uninitialized dynptr */
+SEC("?xdp")
+int iterator_invalid2(struct xdp_md *xdp)
+{
+ struct bpf_dynptr ptr;
+
+ /* this should fail */
+ bpf_dynptr_iterator(&ptr, iterator_callback1, NULL, 0);
+
+ return 0;
+}
+
+static int iterator_callback2(struct bpf_dynptr *ptr, void *ctx)
+{
+ /* this should fail */
+ bpf_ringbuf_reserve_dynptr(&ringbuf, val, 0, ptr);
+
+ bpf_ringbuf_submit_dynptr(ptr, 0);
+
+ return 0;
+}
+
+/* An already-initialized dynptr can't be initialized again
+ * within an iterator callback function
+ */
+SEC("?raw_tp")
+int iterator_invalid3(void *ctx)
+{
+ struct bpf_dynptr ptr;
+
+ bpf_ringbuf_reserve_dynptr(&ringbuf, val, 0, &ptr);
+
+ bpf_dynptr_iterator(&ptr, iterator_callback2, NULL, 0);
+
+ return 0;
+}
+
+static int iterator_callback3(struct bpf_dynptr *ptr, void *ctx)
+{
+ char write_data[64] = "hello there, world!!";
+
+ bpf_dynptr_write(ptr, 0, write_data, sizeof(write_data), 0);
+
+ bpf_ringbuf_submit_dynptr(ptr, 0);
+
+ return 0;
+}
+
+/* The dynptr that is being iterated on can't be released in an
+ * iterator callback.
+ *
+ * Currently, the verifier doesn't strictly check for this since
+ * it only runs the callback once when verifying. For now, we
+ * use the fact that the verifier doesn't mark the reference in
+ * the parent func state as released if it's released in the
+ * callback. This is what we currently lean on in bpf_loop() as
+ * well. This is a bit of a hack for now, and will need to be
+ * addressed more thoroughly in the future.
+ */
+SEC("?raw_tp")
+int iterator_invalid4(void *ctx)
+{
+ struct bpf_dynptr ptr;
+
+ bpf_ringbuf_reserve_dynptr(&ringbuf, val, 0, &ptr);
+
+ bpf_dynptr_iterator(&ptr, iterator_callback3, NULL, 0);
+
+ return 0;
+}
+
+static int iterator_callback4(struct bpf_dynptr *ptr, void *ctx)
+{
+ bpf_ringbuf_submit_dynptr(ctx, 0);
+
+ return 0;
+}
+
+/* If a dynptr is passed in as the callback ctx, the dynptr
+ * can't be released.
+ *
+ * Currently, the verifier doesn't strictly check for this since
+ * it only runs the callback once when verifying. For now, we
+ * use the fact that the verifier doesn't mark the reference in
+ * the parent func state as released if it's released in the
+ * callback. This is what we currently lean on in bpf_loop() as
+ * well. This is a bit of a hack for now, and will need to be
+ * addressed more thoroughly in the future.
+ */
+SEC("?raw_tp")
+int iterator_invalid5(void *ctx)
+{
+ struct bpf_dynptr ptr;
+
+ bpf_ringbuf_reserve_dynptr(&ringbuf, val, 0, &ptr);
+
+ bpf_dynptr_iterator(&ptr, iterator_callback4, &ptr, 0);
+
+ return 0;
+}
diff --git a/tools/testing/selftests/bpf/progs/dynptr_success.c b/tools/testing/selftests/bpf/progs/dynptr_success.c
index 8ed3ef201284..22164ad6df9d 100644
--- a/tools/testing/selftests/bpf/progs/dynptr_success.c
+++ b/tools/testing/selftests/bpf/progs/dynptr_success.c
@@ -1,11 +1,11 @@
// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2022 Facebook */
+#include <errno.h>
#include <string.h>
#include <linux/bpf.h>
-#include <bpf/bpf_helpers.h>
#include "bpf_misc.h"
-#include "errno.h"
+#include <bpf/bpf_helpers.h>
char _license[] SEC("license") = "GPL";
@@ -29,6 +29,13 @@ struct {
__type(value, __u32);
} array_map SEC(".maps");
+struct {
+ __uint(type, BPF_MAP_TYPE_ARRAY);
+ __uint(max_entries, 1);
+ __type(key, __u32);
+ __uint(value_size, 64);
+} array_map2 SEC(".maps");
+
SEC("tp/syscalls/sys_enter_nanosleep")
int test_read_write(void *ctx)
{
@@ -194,3 +201,543 @@ int test_skb_readonly(struct __sk_buff *skb)
return 0;
}
+
+SEC("tp/syscalls/sys_enter_nanosleep")
+int test_advance_trim(void *ctx)
+{
+ struct bpf_dynptr ptr;
+ __u32 bytes = 64;
+ __u32 off = 10;
+ __u32 trim = 5;
+
+ if (bpf_get_current_pid_tgid() >> 32 != pid)
+ return 0;
+
+ err = bpf_ringbuf_reserve_dynptr(&ringbuf, bytes, 0, &ptr);
+ if (err) {
+ err = 1;
+ goto done;
+ }
+
+ if (bpf_dynptr_get_size(&ptr) != bytes) {
+ err = 2;
+ goto done;
+ }
+
+ /* Advance the dynptr by off */
+ err = bpf_dynptr_advance(&ptr, off);
+ if (err) {
+ err = 3;
+ goto done;
+ }
+
+ /* Check that the dynptr off and size were adjusted correctly */
+ if (bpf_dynptr_get_offset(&ptr) != off) {
+ err = 4;
+ goto done;
+ }
+ if (bpf_dynptr_get_size(&ptr) != bytes - off) {
+ err = 5;
+ goto done;
+ }
+
+ /* Trim the dynptr */
+ err = bpf_dynptr_trim(&ptr, trim);
+ if (err) {
+ err = 6;
+ goto done;
+ }
+
+ /* Check that the off was unaffected */
+ if (bpf_dynptr_get_offset(&ptr) != off) {
+ err = 7;
+ goto done;
+ }
+ /* Check that the size was adjusted correctly */
+ if (bpf_dynptr_get_size(&ptr) != bytes - off - trim) {
+ err = 8;
+ goto done;
+ }
+
+done:
+ bpf_ringbuf_discard_dynptr(&ptr, 0);
+ return 0;
+}
+
+SEC("tp/syscalls/sys_enter_nanosleep")
+int test_advance_trim_err(void *ctx)
+{
+ char write_data[45] = "hello there, world!!";
+ struct bpf_dynptr ptr;
+ __u32 trim_size = 10;
+ __u32 size = 64;
+ __u32 off = 10;
+
+ if (bpf_get_current_pid_tgid() >> 32 != pid)
+ return 0;
+
+ if (bpf_ringbuf_reserve_dynptr(&ringbuf, size, 0, &ptr)) {
+ err = 1;
+ goto done;
+ }
+
+ /* Check that you can't advance beyond size of dynptr data */
+ if (bpf_dynptr_advance(&ptr, size + 1) != -ERANGE) {
+ err = 2;
+ goto done;
+ }
+
+ if (bpf_dynptr_advance(&ptr, off)) {
+ err = 3;
+ goto done;
+ }
+
+ /* Check that you can't trim more than size of dynptr data */
+ if (bpf_dynptr_trim(&ptr, size - off + 1) != -ERANGE) {
+ err = 4;
+ goto done;
+ }
+
+ /* Check that you can't write more bytes than available into the dynptr
+ * after you've trimmed it
+ */
+ if (bpf_dynptr_trim(&ptr, trim_size)) {
+ err = 5;
+ goto done;
+ }
+
+ if (bpf_dynptr_write(&ptr, 0, &write_data, sizeof(write_data), 0) != -E2BIG) {
+ err = 6;
+ goto done;
+ }
+
+ /* Check that even after advancing / trimming, submitting/discarding
+ * a ringbuf dynptr works
+ */
+ bpf_ringbuf_submit_dynptr(&ptr, 0);
+ return 0;
+
+done:
+ bpf_ringbuf_discard_dynptr(&ptr, 0);
+ return 0;
+}
+
+SEC("tp/syscalls/sys_enter_nanosleep")
+int test_zero_size_dynptr(void *ctx)
+{
+ char write_data = 'x', read_data;
+ struct bpf_dynptr ptr;
+ __u32 size = 64;
+ __u32 off = 10;
+
+ if (bpf_get_current_pid_tgid() >> 32 != pid)
+ return 0;
+
+ /* check that you can reserve a dynamic size reservation */
+ if (bpf_ringbuf_reserve_dynptr(&ringbuf, size, 0, &ptr)) {
+ err = 1;
+ goto done;
+ }
+
+ /* After this, the dynptr has a size of 0 */
+ if (bpf_dynptr_advance(&ptr, size)) {
+ err = 2;
+ goto done;
+ }
+
+ /* Test that reading + writing non-zero bytes is not ok */
+ if (bpf_dynptr_read(&read_data, sizeof(read_data), &ptr, 0, 0) != -E2BIG) {
+ err = 3;
+ goto done;
+ }
+
+ if (bpf_dynptr_write(&ptr, 0, &write_data, sizeof(write_data), 0) != -E2BIG) {
+ err = 4;
+ goto done;
+ }
+
+ /* Test that reading + writing 0 bytes from a 0-size dynptr is ok */
+ if (bpf_dynptr_read(&read_data, 0, &ptr, 0, 0)) {
+ err = 5;
+ goto done;
+ }
+
+ if (bpf_dynptr_write(&ptr, 0, &write_data, 0, 0)) {
+ err = 6;
+ goto done;
+ }
+
+ err = 0;
+
+done:
+ bpf_ringbuf_discard_dynptr(&ptr, 0);
+ return 0;
+}
+
+SEC("tp/syscalls/sys_enter_nanosleep")
+int test_dynptr_is_null(void *ctx)
+{
+ struct bpf_dynptr ptr1;
+ struct bpf_dynptr ptr2;
+ __u64 size = 4;
+
+ if (bpf_get_current_pid_tgid() >> 32 != pid)
+ return 0;
+
+ /* Pass in invalid flags, get back an invalid dynptr */
+ if (bpf_ringbuf_reserve_dynptr(&ringbuf, size, 123, &ptr1) != -EINVAL) {
+ err = 1;
+ goto exit_early;
+ }
+
+ /* Test that the invalid dynptr is null */
+ if (!bpf_dynptr_is_null(&ptr1)) {
+ err = 2;
+ goto exit_early;
+ }
+
+ /* Get a valid dynptr */
+ if (bpf_ringbuf_reserve_dynptr(&ringbuf, size, 0, &ptr2)) {
+ err = 3;
+ goto exit;
+ }
+
+ /* Test that the valid dynptr is not null */
+ if (bpf_dynptr_is_null(&ptr2)) {
+ err = 4;
+ goto exit;
+ }
+
+exit:
+ bpf_ringbuf_discard_dynptr(&ptr2, 0);
+exit_early:
+ bpf_ringbuf_discard_dynptr(&ptr1, 0);
+ return 0;
+}
+
+SEC("cgroup_skb/egress")
+int test_dynptr_is_rdonly(struct __sk_buff *skb)
+{
+ struct bpf_dynptr ptr1;
+ struct bpf_dynptr ptr2;
+ struct bpf_dynptr ptr3;
+
+ /* Pass in invalid flags, get back an invalid dynptr */
+ if (bpf_dynptr_from_skb(skb, 123, &ptr1) != -EINVAL) {
+ err = 1;
+ return 0;
+ }
+
+ /* Test that an invalid dynptr is_rdonly returns false */
+ if (bpf_dynptr_is_rdonly(&ptr1)) {
+ err = 2;
+ return 0;
+ }
+
+ /* Get a read-only dynptr */
+ if (bpf_dynptr_from_skb(skb, 0, &ptr2)) {
+ err = 3;
+ return 0;
+ }
+
+ /* Test that the dynptr is read-only */
+ if (!bpf_dynptr_is_rdonly(&ptr2)) {
+ err = 4;
+ return 0;
+ }
+
+ /* Get a read-writeable dynptr */
+ if (bpf_ringbuf_reserve_dynptr(&ringbuf, 64, 0, &ptr3)) {
+ err = 5;
+ goto done;
+ }
+
+ /* Test that the dynptr is read-only */
+ if (bpf_dynptr_is_rdonly(&ptr3)) {
+ err = 6;
+ goto done;
+ }
+
+done:
+ bpf_ringbuf_discard_dynptr(&ptr3, 0);
+ return 0;
+}
+
+SEC("cgroup_skb/egress")
+int test_dynptr_clone(struct __sk_buff *skb)
+{
+ struct bpf_dynptr ptr1;
+ struct bpf_dynptr ptr2;
+ __u32 off = 2, size;
+
+ /* Get a dynptr */
+ if (bpf_dynptr_from_skb(skb, 0, &ptr1)) {
+ err = 1;
+ return 0;
+ }
+
+ if (bpf_dynptr_advance(&ptr1, off)) {
+ err = 2;
+ return 0;
+ }
+
+ /* Clone the dynptr */
+ if (bpf_dynptr_clone(&ptr1, &ptr2)) {
+ err = 3;
+ return 0;
+ }
+
+ size = bpf_dynptr_get_size(&ptr1);
+
+ /* Check that the clone has the same offset, size, and rd-only */
+ if (bpf_dynptr_get_size(&ptr2) != size) {
+ err = 4;
+ return 0;
+ }
+
+ if (bpf_dynptr_get_offset(&ptr2) != off) {
+ err = 5;
+ return 0;
+ }
+
+ if (bpf_dynptr_is_rdonly(&ptr2) != bpf_dynptr_is_rdonly(&ptr1)) {
+ err = 6;
+ return 0;
+ }
+
+ /* Advance and trim the original dynptr */
+ bpf_dynptr_advance(&ptr1, 50);
+ bpf_dynptr_trim(&ptr1, 50);
+
+ /* Check that only original dynptr was affected, and the clone wasn't */
+ if (bpf_dynptr_get_offset(&ptr2) != off) {
+ err = 7;
+ return 0;
+ }
+
+ if (bpf_dynptr_get_size(&ptr2) != size) {
+ err = 8;
+ return 0;
+ }
+
+ return 0;
+}
+
+struct iter_ctx {
+ /* if set, this means try to iterate more bytes than available */
+ bool trigger_err_erange;
+ /* iteration index */
+ int index;
+ /* offset at the first iteration */
+ __u32 start_off;
+ /* if non-zero, this indicates the offset to stop at */
+ __u32 stop_off;
+ /* number of bytes to advance by each time */
+ __u32 iter_bytes;
+ /* total number of bytes iterated on */
+ __u32 total_bytes;
+};
+
+static int iter_callback(struct bpf_dynptr *ptr, struct iter_ctx *ctx)
+{
+ if (ctx->trigger_err_erange)
+ return bpf_dynptr_get_size(ptr) + 1;
+
+ if (ctx->index == 0)
+ ctx->start_off = bpf_dynptr_get_offset(ptr);
+ else if (ctx->stop_off == ctx->total_bytes)
+ return 0;
+
+ ctx->index++;
+ ctx->total_bytes += ctx->iter_bytes;
+
+ if (bpf_dynptr_get_size(ptr) == 0)
+ return 0;
+
+ return ctx->iter_bytes;
+}
+
+SEC("cgroup_skb/egress")
+int test_dynptr_iterator(struct __sk_buff *skb)
+{
+ struct iter_ctx ctx = { .iter_bytes = 1, };
+ struct bpf_dynptr ptr;
+ __u32 off = 1, size;
+
+ /* Get a dynptr */
+ if (bpf_dynptr_from_skb(skb, 0, &ptr)) {
+ err = 1;
+ return 0;
+ }
+
+ if (bpf_dynptr_advance(&ptr, off)) {
+ err = 2;
+ return 0;
+ }
+
+ size = bpf_dynptr_get_size(&ptr);
+
+ /* Test the case where the callback tries to advance by more
+ * bytes than available
+ */
+ ctx.trigger_err_erange = true;
+ if (bpf_dynptr_iterator(&ptr, iter_callback, &ctx, 0) != -ERANGE) {
+ err = 3;
+ return 0;
+ }
+ if (bpf_dynptr_get_size(&ptr) != size) {
+ err = 4;
+ return 0;
+ }
+ if (bpf_dynptr_get_offset(&ptr) != off) {
+ err = 5;
+ return 0;
+ }
+ ctx.trigger_err_erange = false;
+
+ /* Test the case where we stop after a certain number of bytes */
+ ctx.stop_off = 15;
+ if (bpf_dynptr_iterator(&ptr, iter_callback, &ctx, 0)) {
+ err = 6;
+ return 0;
+ }
+ if (bpf_dynptr_get_size(&ptr) != size - ctx.stop_off) {
+ err = 7;
+ return 0;
+ }
+ if (bpf_dynptr_get_offset(&ptr) != off + ctx.stop_off) {
+ err = 8;
+ return 0;
+ }
+
+ /* Test that the iteration started at the current offset of the dynptr */
+ if (ctx.start_off != off) {
+ err = 9;
+ return 0;
+ }
+
+ /* Test that we iterate to the end */
+ ctx.stop_off = 0;
+ if (bpf_dynptr_iterator(&ptr, iter_callback, &ctx, 0)) {
+ err = 10;
+ return 0;
+ }
+ if (bpf_dynptr_get_size(&ptr) != 0) {
+ err = 11;
+ return 0;
+ }
+ if (bpf_dynptr_get_offset(&ptr) != off + size) {
+ err = 12;
+ return 0;
+ }
+
+ return 0;
+}
+
+static char values[3][64] = {};
+
+#define MAX_STRINGS_LEN 10
+static int parse_strings_callback(struct bpf_dynptr *ptr, int *nr_values)
+{
+ __u32 size = bpf_dynptr_get_size(ptr);
+ char buf[MAX_STRINGS_LEN] = {};
+ char *data;
+ int i, j, k;
+ int err;
+
+ if (size < MAX_STRINGS_LEN) {
+ err = bpf_dynptr_read(buf, size, ptr, 0, 0);
+ if (err)
+ return err;
+ data = buf;
+ } else {
+ data = bpf_dynptr_data(ptr, 0, MAX_STRINGS_LEN);
+ if (!data)
+ return -ENOENT;
+ size = MAX_STRINGS_LEN;
+ }
+
+ for (i = 0; i < size; i++) {
+ if (data[i] != '=')
+ continue;
+
+ for (j = i; j < size - i; j++) {
+ int index = 0;
+
+ if (data[j] != '/')
+ continue;
+
+ for (k = i + 1; k < j; k++) {
+ values[*nr_values][index] = data[k];
+ index += 1;
+ }
+
+ *nr_values += 1;
+ return j;
+ }
+
+ return -ENOENT;
+ }
+
+ return 0;
+}
+
+SEC("tp/syscalls/sys_enter_nanosleep")
+int iterator_parse_strings(void *ctx)
+{
+ char val[64] = "x=foo/y=bar/z=baz/";
+ struct bpf_dynptr ptr;
+ __u32 map_val_size;
+ int nr_values = 0;
+ __u32 key = 0;
+ char *map_val;
+
+ if (bpf_get_current_pid_tgid() >> 32 != pid)
+ return 0;
+
+ map_val_size = sizeof(val);
+
+ if (bpf_map_update_elem(&array_map2, &key, &val, 0)) {
+ err = 1;
+ return 0;
+ }
+
+ map_val = bpf_map_lookup_elem(&array_map2, &key);
+ if (!map_val) {
+ err = 2;
+ return 0;
+ }
+
+ if (bpf_dynptr_from_mem(map_val, map_val_size, 0, &ptr)) {
+ err = 3;
+ return 0;
+ }
+
+ if (bpf_dynptr_iterator(&ptr, parse_strings_callback,
+ &nr_values, 0)) {
+ err = 4;
+ return 0;
+ }
+
+ if (nr_values != 3) {
+ err = 8;
+ return 0;
+ }
+
+ if (memcmp(values[0], "foo", sizeof("foo"))) {
+ err = 5;
+ return 0;
+ }
+
+ if (memcmp(values[1], "bar", sizeof("bar"))) {
+ err = 6;
+ return 0;
+ }
+
+ if (memcmp(values[2], "baz", sizeof("baz"))) {
+ err = 7;
+ return 0;
+ }
+
+ return 0;
+}
--
2.30.2
