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	 83dff60171
			
		
	
	
		83dff60171
		
	
	
	
	
		
			
			Add 3 test cases for skb dynptr used in tp_btf: - test_dynptr_skb_tp_btf: use skb dynptr in tp_btf and make sure it is read-only. - skb_invalid_ctx_fentry/skb_invalid_ctx_fexit: bpf_dynptr_from_skb should fail in fentry/fexit. In test_dynptr_skb_tp_btf, to trigger the tracepoint in kfree_skb, test_pkt_access is used for its test_run, as in kfree_skb.c. Because the test process is different from others, a new setup type is defined, i.e., SETUP_SKB_PROG_TP. The result is like: $ ./test_progs -t 'dynptr/test_dynptr_skb_tp_btf' #84/14 dynptr/test_dynptr_skb_tp_btf:OK #84 dynptr:OK #127 kfunc_dynptr_param:OK Summary: 2/1 PASSED, 0 SKIPPED, 0 FAILED $ ./test_progs -t 'dynptr/skb_invalid_ctx_f' #84/85 dynptr/skb_invalid_ctx_fentry:OK #84/86 dynptr/skb_invalid_ctx_fexit:OK #84 dynptr:OK #127 kfunc_dynptr_param:OK Summary: 2/2 PASSED, 0 SKIPPED, 0 FAILED Also fix two coding style nits (change spaces to tabs). Signed-off-by: Philo Lu <lulie@linux.alibaba.com> Link: https://lore.kernel.org/r/20240911033719.91468-6-lulie@linux.alibaba.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
		
			
				
	
	
		
			1737 lines
		
	
	
	
		
			36 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			1737 lines
		
	
	
	
		
			36 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| // SPDX-License-Identifier: GPL-2.0
 | |
| /* Copyright (c) 2022 Facebook */
 | |
| 
 | |
| #include <errno.h>
 | |
| #include <string.h>
 | |
| #include <stdbool.h>
 | |
| #include <linux/bpf.h>
 | |
| #include <bpf/bpf_helpers.h>
 | |
| #include <bpf/bpf_tracing.h>
 | |
| #include <linux/if_ether.h>
 | |
| #include "bpf_misc.h"
 | |
| #include "bpf_kfuncs.h"
 | |
| 
 | |
| char _license[] SEC("license") = "GPL";
 | |
| 
 | |
| struct test_info {
 | |
| 	int x;
 | |
| 	struct bpf_dynptr ptr;
 | |
| };
 | |
| 
 | |
| struct {
 | |
| 	__uint(type, BPF_MAP_TYPE_ARRAY);
 | |
| 	__uint(max_entries, 1);
 | |
| 	__type(key, __u32);
 | |
| 	__type(value, struct bpf_dynptr);
 | |
| } array_map1 SEC(".maps");
 | |
| 
 | |
| struct {
 | |
| 	__uint(type, BPF_MAP_TYPE_ARRAY);
 | |
| 	__uint(max_entries, 1);
 | |
| 	__type(key, __u32);
 | |
| 	__type(value, struct test_info);
 | |
| } array_map2 SEC(".maps");
 | |
| 
 | |
| struct {
 | |
| 	__uint(type, BPF_MAP_TYPE_ARRAY);
 | |
| 	__uint(max_entries, 1);
 | |
| 	__type(key, __u32);
 | |
| 	__type(value, __u32);
 | |
| } array_map3 SEC(".maps");
 | |
| 
 | |
| struct {
 | |
| 	__uint(type, BPF_MAP_TYPE_ARRAY);
 | |
| 	__uint(max_entries, 1);
 | |
| 	__type(key, __u32);
 | |
| 	__type(value, __u64);
 | |
| } array_map4 SEC(".maps");
 | |
| 
 | |
| struct sample {
 | |
| 	int pid;
 | |
| 	long value;
 | |
| 	char comm[16];
 | |
| };
 | |
| 
 | |
| struct {
 | |
| 	__uint(type, BPF_MAP_TYPE_RINGBUF);
 | |
| 	__uint(max_entries, 4096);
 | |
| } ringbuf SEC(".maps");
 | |
| 
 | |
| int err, val;
 | |
| 
 | |
| static int get_map_val_dynptr(struct bpf_dynptr *ptr)
 | |
| {
 | |
| 	__u32 key = 0, *map_val;
 | |
| 
 | |
| 	bpf_map_update_elem(&array_map3, &key, &val, 0);
 | |
| 
 | |
| 	map_val = bpf_map_lookup_elem(&array_map3, &key);
 | |
| 	if (!map_val)
 | |
| 		return -ENOENT;
 | |
| 
 | |
| 	bpf_dynptr_from_mem(map_val, sizeof(*map_val), 0, ptr);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /* Every bpf_ringbuf_reserve_dynptr call must have a corresponding
 | |
|  * bpf_ringbuf_submit/discard_dynptr call
 | |
|  */
 | |
| SEC("?raw_tp")
 | |
| __failure __msg("Unreleased reference id=2")
 | |
| int ringbuf_missing_release1(void *ctx)
 | |
| {
 | |
| 	struct bpf_dynptr ptr = {};
 | |
| 
 | |
| 	bpf_ringbuf_reserve_dynptr(&ringbuf, val, 0, &ptr);
 | |
| 
 | |
| 	/* missing a call to bpf_ringbuf_discard/submit_dynptr */
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| SEC("?raw_tp")
 | |
| __failure __msg("Unreleased reference id=4")
 | |
| int ringbuf_missing_release2(void *ctx)
 | |
| {
 | |
| 	struct bpf_dynptr ptr1, ptr2;
 | |
| 	struct sample *sample;
 | |
| 
 | |
| 	bpf_ringbuf_reserve_dynptr(&ringbuf, sizeof(*sample), 0, &ptr1);
 | |
| 	bpf_ringbuf_reserve_dynptr(&ringbuf, sizeof(*sample), 0, &ptr2);
 | |
| 
 | |
| 	sample = bpf_dynptr_data(&ptr1, 0, sizeof(*sample));
 | |
| 	if (!sample) {
 | |
| 		bpf_ringbuf_discard_dynptr(&ptr1, 0);
 | |
| 		bpf_ringbuf_discard_dynptr(&ptr2, 0);
 | |
| 		return 0;
 | |
| 	}
 | |
| 
 | |
| 	bpf_ringbuf_submit_dynptr(&ptr1, 0);
 | |
| 
 | |
| 	/* missing a call to bpf_ringbuf_discard/submit_dynptr on ptr2 */
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static int missing_release_callback_fn(__u32 index, void *data)
 | |
| {
 | |
| 	struct bpf_dynptr ptr;
 | |
| 
 | |
| 	bpf_ringbuf_reserve_dynptr(&ringbuf, val, 0, &ptr);
 | |
| 
 | |
| 	/* missing a call to bpf_ringbuf_discard/submit_dynptr */
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /* Any dynptr initialized within a callback must have bpf_dynptr_put called */
 | |
| SEC("?raw_tp")
 | |
| __failure __msg("Unreleased reference id")
 | |
| int ringbuf_missing_release_callback(void *ctx)
 | |
| {
 | |
| 	bpf_loop(10, missing_release_callback_fn, NULL, 0);
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /* Can't call bpf_ringbuf_submit/discard_dynptr on a non-initialized dynptr */
 | |
| SEC("?raw_tp")
 | |
| __failure __msg("arg 1 is an unacquired reference")
 | |
| int ringbuf_release_uninit_dynptr(void *ctx)
 | |
| {
 | |
| 	struct bpf_dynptr ptr;
 | |
| 
 | |
| 	/* this should fail */
 | |
| 	bpf_ringbuf_submit_dynptr(&ptr, 0);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /* A dynptr can't be used after it has been invalidated */
 | |
| SEC("?raw_tp")
 | |
| __failure __msg("Expected an initialized dynptr as arg #3")
 | |
| int use_after_invalid(void *ctx)
 | |
| {
 | |
| 	struct bpf_dynptr ptr;
 | |
| 	char read_data[64];
 | |
| 
 | |
| 	bpf_ringbuf_reserve_dynptr(&ringbuf, sizeof(read_data), 0, &ptr);
 | |
| 
 | |
| 	bpf_dynptr_read(read_data, sizeof(read_data), &ptr, 0, 0);
 | |
| 
 | |
| 	bpf_ringbuf_submit_dynptr(&ptr, 0);
 | |
| 
 | |
| 	/* this should fail */
 | |
| 	bpf_dynptr_read(read_data, sizeof(read_data), &ptr, 0, 0);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /* Can't call non-dynptr ringbuf APIs on a dynptr ringbuf sample */
 | |
| SEC("?raw_tp")
 | |
| __failure __msg("type=mem expected=ringbuf_mem")
 | |
| int ringbuf_invalid_api(void *ctx)
 | |
| {
 | |
| 	struct bpf_dynptr ptr;
 | |
| 	struct sample *sample;
 | |
| 
 | |
| 	bpf_ringbuf_reserve_dynptr(&ringbuf, sizeof(*sample), 0, &ptr);
 | |
| 	sample = bpf_dynptr_data(&ptr, 0, sizeof(*sample));
 | |
| 	if (!sample)
 | |
| 		goto done;
 | |
| 
 | |
| 	sample->pid = 123;
 | |
| 
 | |
| 	/* invalid API use. need to use dynptr API to submit/discard */
 | |
| 	bpf_ringbuf_submit(sample, 0);
 | |
| 
 | |
| done:
 | |
| 	bpf_ringbuf_discard_dynptr(&ptr, 0);
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /* Can't add a dynptr to a map */
 | |
| SEC("?raw_tp")
 | |
| __failure __msg("invalid indirect read from stack")
 | |
| int add_dynptr_to_map1(void *ctx)
 | |
| {
 | |
| 	struct bpf_dynptr ptr;
 | |
| 	int key = 0;
 | |
| 
 | |
| 	bpf_ringbuf_reserve_dynptr(&ringbuf, val, 0, &ptr);
 | |
| 
 | |
| 	/* this should fail */
 | |
| 	bpf_map_update_elem(&array_map1, &key, &ptr, 0);
 | |
| 
 | |
| 	bpf_ringbuf_submit_dynptr(&ptr, 0);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /* Can't add a struct with an embedded dynptr to a map */
 | |
| SEC("?raw_tp")
 | |
| __failure __msg("invalid indirect read from stack")
 | |
| int add_dynptr_to_map2(void *ctx)
 | |
| {
 | |
| 	struct test_info x;
 | |
| 	int key = 0;
 | |
| 
 | |
| 	bpf_ringbuf_reserve_dynptr(&ringbuf, val, 0, &x.ptr);
 | |
| 
 | |
| 	/* this should fail */
 | |
| 	bpf_map_update_elem(&array_map2, &key, &x, 0);
 | |
| 
 | |
| 	bpf_ringbuf_submit_dynptr(&x.ptr, 0);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /* A data slice can't be accessed out of bounds */
 | |
| SEC("?raw_tp")
 | |
| __failure __msg("value is outside of the allowed memory range")
 | |
| int data_slice_out_of_bounds_ringbuf(void *ctx)
 | |
| {
 | |
| 	struct bpf_dynptr ptr;
 | |
| 	void *data;
 | |
| 
 | |
| 	bpf_ringbuf_reserve_dynptr(&ringbuf, 8, 0, &ptr);
 | |
| 
 | |
| 	data  = bpf_dynptr_data(&ptr, 0, 8);
 | |
| 	if (!data)
 | |
| 		goto done;
 | |
| 
 | |
| 	/* can't index out of bounds of the data slice */
 | |
| 	val = *((char *)data + 8);
 | |
| 
 | |
| done:
 | |
| 	bpf_ringbuf_submit_dynptr(&ptr, 0);
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /* A data slice can't be accessed out of bounds */
 | |
| SEC("?tc")
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| __failure __msg("value is outside of the allowed memory range")
 | |
| int data_slice_out_of_bounds_skb(struct __sk_buff *skb)
 | |
| {
 | |
| 	struct bpf_dynptr ptr;
 | |
| 	struct ethhdr *hdr;
 | |
| 	char buffer[sizeof(*hdr)] = {};
 | |
| 
 | |
| 	bpf_dynptr_from_skb(skb, 0, &ptr);
 | |
| 
 | |
| 	hdr = bpf_dynptr_slice_rdwr(&ptr, 0, buffer, sizeof(buffer));
 | |
| 	if (!hdr)
 | |
| 		return SK_DROP;
 | |
| 
 | |
| 	/* this should fail */
 | |
| 	*(__u8*)(hdr + 1) = 1;
 | |
| 
 | |
| 	return SK_PASS;
 | |
| }
 | |
| 
 | |
| SEC("?raw_tp")
 | |
| __failure __msg("value is outside of the allowed memory range")
 | |
| int data_slice_out_of_bounds_map_value(void *ctx)
 | |
| {
 | |
| 	__u32 map_val;
 | |
| 	struct bpf_dynptr ptr;
 | |
| 	void *data;
 | |
| 
 | |
| 	get_map_val_dynptr(&ptr);
 | |
| 
 | |
| 	data  = bpf_dynptr_data(&ptr, 0, sizeof(map_val));
 | |
| 	if (!data)
 | |
| 		return 0;
 | |
| 
 | |
| 	/* can't index out of bounds of the data slice */
 | |
| 	val = *((char *)data + (sizeof(map_val) + 1));
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /* A data slice can't be used after it has been released */
 | |
| SEC("?raw_tp")
 | |
| __failure __msg("invalid mem access 'scalar'")
 | |
| int data_slice_use_after_release1(void *ctx)
 | |
| {
 | |
| 	struct bpf_dynptr ptr;
 | |
| 	struct sample *sample;
 | |
| 
 | |
| 	bpf_ringbuf_reserve_dynptr(&ringbuf, sizeof(*sample), 0, &ptr);
 | |
| 	sample = bpf_dynptr_data(&ptr, 0, sizeof(*sample));
 | |
| 	if (!sample)
 | |
| 		goto done;
 | |
| 
 | |
| 	sample->pid = 123;
 | |
| 
 | |
| 	bpf_ringbuf_submit_dynptr(&ptr, 0);
 | |
| 
 | |
| 	/* this should fail */
 | |
| 	val = sample->pid;
 | |
| 
 | |
| 	return 0;
 | |
| 
 | |
| done:
 | |
| 	bpf_ringbuf_discard_dynptr(&ptr, 0);
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /* A data slice can't be used after it has been released.
 | |
|  *
 | |
|  * This tests the case where the data slice tracks a dynptr (ptr2)
 | |
|  * that is at a non-zero offset from the frame pointer (ptr1 is at fp,
 | |
|  * ptr2 is at fp - 16).
 | |
|  */
 | |
| SEC("?raw_tp")
 | |
| __failure __msg("invalid mem access 'scalar'")
 | |
| int data_slice_use_after_release2(void *ctx)
 | |
| {
 | |
| 	struct bpf_dynptr ptr1, ptr2;
 | |
| 	struct sample *sample;
 | |
| 
 | |
| 	bpf_ringbuf_reserve_dynptr(&ringbuf, 64, 0, &ptr1);
 | |
| 	bpf_ringbuf_reserve_dynptr(&ringbuf, sizeof(*sample), 0, &ptr2);
 | |
| 
 | |
| 	sample = bpf_dynptr_data(&ptr2, 0, sizeof(*sample));
 | |
| 	if (!sample)
 | |
| 		goto done;
 | |
| 
 | |
| 	sample->pid = 23;
 | |
| 
 | |
| 	bpf_ringbuf_submit_dynptr(&ptr2, 0);
 | |
| 
 | |
| 	/* this should fail */
 | |
| 	sample->pid = 23;
 | |
| 
 | |
| 	bpf_ringbuf_submit_dynptr(&ptr1, 0);
 | |
| 
 | |
| 	return 0;
 | |
| 
 | |
| done:
 | |
| 	bpf_ringbuf_discard_dynptr(&ptr2, 0);
 | |
| 	bpf_ringbuf_discard_dynptr(&ptr1, 0);
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /* A data slice must be first checked for NULL */
 | |
| SEC("?raw_tp")
 | |
| __failure __msg("invalid mem access 'mem_or_null'")
 | |
| int data_slice_missing_null_check1(void *ctx)
 | |
| {
 | |
| 	struct bpf_dynptr ptr;
 | |
| 	void *data;
 | |
| 
 | |
| 	bpf_ringbuf_reserve_dynptr(&ringbuf, 8, 0, &ptr);
 | |
| 
 | |
| 	data  = bpf_dynptr_data(&ptr, 0, 8);
 | |
| 
 | |
| 	/* missing if (!data) check */
 | |
| 
 | |
| 	/* this should fail */
 | |
| 	*(__u8 *)data = 3;
 | |
| 
 | |
| 	bpf_ringbuf_submit_dynptr(&ptr, 0);
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /* A data slice can't be dereferenced if it wasn't checked for null */
 | |
| SEC("?raw_tp")
 | |
| __failure __msg("invalid mem access 'mem_or_null'")
 | |
| int data_slice_missing_null_check2(void *ctx)
 | |
| {
 | |
| 	struct bpf_dynptr ptr;
 | |
| 	__u64 *data1, *data2;
 | |
| 
 | |
| 	bpf_ringbuf_reserve_dynptr(&ringbuf, 16, 0, &ptr);
 | |
| 
 | |
| 	data1 = bpf_dynptr_data(&ptr, 0, 8);
 | |
| 	data2 = bpf_dynptr_data(&ptr, 0, 8);
 | |
| 	if (data1)
 | |
| 		/* this should fail */
 | |
| 		*data2 = 3;
 | |
| 
 | |
| 	bpf_ringbuf_discard_dynptr(&ptr, 0);
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /* Can't pass in a dynptr as an arg to a helper function that doesn't take in a
 | |
|  * dynptr argument
 | |
|  */
 | |
| SEC("?raw_tp")
 | |
| __failure __msg("invalid indirect read from stack")
 | |
| int invalid_helper1(void *ctx)
 | |
| {
 | |
| 	struct bpf_dynptr ptr;
 | |
| 
 | |
| 	get_map_val_dynptr(&ptr);
 | |
| 
 | |
| 	/* this should fail */
 | |
| 	bpf_strncmp((const char *)&ptr, sizeof(ptr), "hello!");
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /* A dynptr can't be passed into a helper function at a non-zero offset */
 | |
| SEC("?raw_tp")
 | |
| __failure __msg("cannot pass in dynptr at an offset=-8")
 | |
| int invalid_helper2(void *ctx)
 | |
| {
 | |
| 	struct bpf_dynptr ptr;
 | |
| 	char read_data[64];
 | |
| 
 | |
| 	get_map_val_dynptr(&ptr);
 | |
| 
 | |
| 	/* this should fail */
 | |
| 	bpf_dynptr_read(read_data, sizeof(read_data), (void *)&ptr + 8, 0, 0);
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /* A bpf_dynptr is invalidated if it's been written into */
 | |
| SEC("?raw_tp")
 | |
| __failure __msg("Expected an initialized dynptr as arg #1")
 | |
| int invalid_write1(void *ctx)
 | |
| {
 | |
| 	struct bpf_dynptr ptr;
 | |
| 	void *data;
 | |
| 	__u8 x = 0;
 | |
| 
 | |
| 	get_map_val_dynptr(&ptr);
 | |
| 
 | |
| 	memcpy(&ptr, &x, sizeof(x));
 | |
| 
 | |
| 	/* this should fail */
 | |
| 	data = bpf_dynptr_data(&ptr, 0, 1);
 | |
| 	__sink(data);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * A bpf_dynptr can't be used as a dynptr if it has been written into at a fixed
 | |
|  * offset
 | |
|  */
 | |
| SEC("?raw_tp")
 | |
| __failure __msg("cannot overwrite referenced dynptr")
 | |
| int invalid_write2(void *ctx)
 | |
| {
 | |
| 	struct bpf_dynptr ptr;
 | |
| 	char read_data[64];
 | |
| 	__u8 x = 0;
 | |
| 
 | |
| 	bpf_ringbuf_reserve_dynptr(&ringbuf, 64, 0, &ptr);
 | |
| 
 | |
| 	memcpy((void *)&ptr + 8, &x, sizeof(x));
 | |
| 
 | |
| 	/* this should fail */
 | |
| 	bpf_dynptr_read(read_data, sizeof(read_data), &ptr, 0, 0);
 | |
| 
 | |
| 	bpf_ringbuf_submit_dynptr(&ptr, 0);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * A bpf_dynptr can't be used as a dynptr if it has been written into at a
 | |
|  * non-const offset
 | |
|  */
 | |
| SEC("?raw_tp")
 | |
| __failure __msg("cannot overwrite referenced dynptr")
 | |
| int invalid_write3(void *ctx)
 | |
| {
 | |
| 	struct bpf_dynptr ptr;
 | |
| 	char stack_buf[16];
 | |
| 	unsigned long len;
 | |
| 	__u8 x = 0;
 | |
| 
 | |
| 	bpf_ringbuf_reserve_dynptr(&ringbuf, 8, 0, &ptr);
 | |
| 
 | |
| 	memcpy(stack_buf, &val, sizeof(val));
 | |
| 	len = stack_buf[0] & 0xf;
 | |
| 
 | |
| 	memcpy((void *)&ptr + len, &x, sizeof(x));
 | |
| 
 | |
| 	/* this should fail */
 | |
| 	bpf_ringbuf_submit_dynptr(&ptr, 0);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static int invalid_write4_callback(__u32 index, void *data)
 | |
| {
 | |
| 	*(__u32 *)data = 123;
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /* If the dynptr is written into in a callback function, it should
 | |
|  * be invalidated as a dynptr
 | |
|  */
 | |
| SEC("?raw_tp")
 | |
| __failure __msg("cannot overwrite referenced dynptr")
 | |
| int invalid_write4(void *ctx)
 | |
| {
 | |
| 	struct bpf_dynptr ptr;
 | |
| 
 | |
| 	bpf_ringbuf_reserve_dynptr(&ringbuf, 64, 0, &ptr);
 | |
| 
 | |
| 	bpf_loop(10, invalid_write4_callback, &ptr, 0);
 | |
| 
 | |
| 	/* this should fail */
 | |
| 	bpf_ringbuf_submit_dynptr(&ptr, 0);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /* A globally-defined bpf_dynptr can't be used (it must reside as a stack frame) */
 | |
| struct bpf_dynptr global_dynptr;
 | |
| 
 | |
| SEC("?raw_tp")
 | |
| __failure __msg("type=map_value expected=fp")
 | |
| int global(void *ctx)
 | |
| {
 | |
| 	/* this should fail */
 | |
| 	bpf_ringbuf_reserve_dynptr(&ringbuf, 16, 0, &global_dynptr);
 | |
| 
 | |
| 	bpf_ringbuf_discard_dynptr(&global_dynptr, 0);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /* A direct read should fail */
 | |
| SEC("?raw_tp")
 | |
| __failure __msg("invalid read from stack")
 | |
| int invalid_read1(void *ctx)
 | |
| {
 | |
| 	struct bpf_dynptr ptr;
 | |
| 
 | |
| 	bpf_ringbuf_reserve_dynptr(&ringbuf, 64, 0, &ptr);
 | |
| 
 | |
| 	/* this should fail */
 | |
| 	val = *(int *)&ptr;
 | |
| 
 | |
| 	bpf_ringbuf_discard_dynptr(&ptr, 0);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /* A direct read at an offset should fail */
 | |
| SEC("?raw_tp")
 | |
| __failure __msg("cannot pass in dynptr at an offset")
 | |
| int invalid_read2(void *ctx)
 | |
| {
 | |
| 	struct bpf_dynptr ptr;
 | |
| 	char read_data[64];
 | |
| 
 | |
| 	get_map_val_dynptr(&ptr);
 | |
| 
 | |
| 	/* this should fail */
 | |
| 	bpf_dynptr_read(read_data, sizeof(read_data), (void *)&ptr + 1, 0, 0);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /* A direct read at an offset into the lower stack slot should fail */
 | |
| SEC("?raw_tp")
 | |
| __failure __msg("invalid read from stack")
 | |
| int invalid_read3(void *ctx)
 | |
| {
 | |
| 	struct bpf_dynptr ptr1, ptr2;
 | |
| 
 | |
| 	bpf_ringbuf_reserve_dynptr(&ringbuf, 16, 0, &ptr1);
 | |
| 	bpf_ringbuf_reserve_dynptr(&ringbuf, 16, 0, &ptr2);
 | |
| 
 | |
| 	/* this should fail */
 | |
| 	memcpy(&val, (void *)&ptr1 + 8, sizeof(val));
 | |
| 
 | |
| 	bpf_ringbuf_discard_dynptr(&ptr1, 0);
 | |
| 	bpf_ringbuf_discard_dynptr(&ptr2, 0);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static int invalid_read4_callback(__u32 index, void *data)
 | |
| {
 | |
| 	/* this should fail */
 | |
| 	val = *(__u32 *)data;
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /* A direct read within a callback function should fail */
 | |
| SEC("?raw_tp")
 | |
| __failure __msg("invalid read from stack")
 | |
| int invalid_read4(void *ctx)
 | |
| {
 | |
| 	struct bpf_dynptr ptr;
 | |
| 
 | |
| 	bpf_ringbuf_reserve_dynptr(&ringbuf, 64, 0, &ptr);
 | |
| 
 | |
| 	bpf_loop(10, invalid_read4_callback, &ptr, 0);
 | |
| 
 | |
| 	bpf_ringbuf_submit_dynptr(&ptr, 0);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /* Initializing a dynptr on an offset should fail */
 | |
| SEC("?raw_tp")
 | |
| __failure __msg("cannot pass in dynptr at an offset=0")
 | |
| int invalid_offset(void *ctx)
 | |
| {
 | |
| 	struct bpf_dynptr ptr;
 | |
| 
 | |
| 	/* this should fail */
 | |
| 	bpf_ringbuf_reserve_dynptr(&ringbuf, 64, 0, &ptr + 1);
 | |
| 
 | |
| 	bpf_ringbuf_discard_dynptr(&ptr, 0);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /* Can't release a dynptr twice */
 | |
| SEC("?raw_tp")
 | |
| __failure __msg("arg 1 is an unacquired reference")
 | |
| int release_twice(void *ctx)
 | |
| {
 | |
| 	struct bpf_dynptr ptr;
 | |
| 
 | |
| 	bpf_ringbuf_reserve_dynptr(&ringbuf, 16, 0, &ptr);
 | |
| 
 | |
| 	bpf_ringbuf_discard_dynptr(&ptr, 0);
 | |
| 
 | |
| 	/* this second release should fail */
 | |
| 	bpf_ringbuf_discard_dynptr(&ptr, 0);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static int release_twice_callback_fn(__u32 index, void *data)
 | |
| {
 | |
| 	/* this should fail */
 | |
| 	bpf_ringbuf_discard_dynptr(data, 0);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /* Test that releasing a dynptr twice, where one of the releases happens
 | |
|  * within a callback function, fails
 | |
|  */
 | |
| SEC("?raw_tp")
 | |
| __failure __msg("arg 1 is an unacquired reference")
 | |
| int release_twice_callback(void *ctx)
 | |
| {
 | |
| 	struct bpf_dynptr ptr;
 | |
| 
 | |
| 	bpf_ringbuf_reserve_dynptr(&ringbuf, 32, 0, &ptr);
 | |
| 
 | |
| 	bpf_ringbuf_discard_dynptr(&ptr, 0);
 | |
| 
 | |
| 	bpf_loop(10, release_twice_callback_fn, &ptr, 0);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /* Reject unsupported local mem types for dynptr_from_mem API */
 | |
| SEC("?raw_tp")
 | |
| __failure __msg("Unsupported reg type fp for bpf_dynptr_from_mem data")
 | |
| int dynptr_from_mem_invalid_api(void *ctx)
 | |
| {
 | |
| 	struct bpf_dynptr ptr;
 | |
| 	int x = 0;
 | |
| 
 | |
| 	/* this should fail */
 | |
| 	bpf_dynptr_from_mem(&x, sizeof(x), 0, &ptr);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| SEC("?tc")
 | |
| __failure __msg("cannot overwrite referenced dynptr") __log_level(2)
 | |
| int dynptr_pruning_overwrite(struct __sk_buff *ctx)
 | |
| {
 | |
| 	asm volatile (
 | |
| 		"r9 = 0xeB9F;				\
 | |
| 		 r6 = %[ringbuf] ll;			\
 | |
| 		 r1 = r6;				\
 | |
| 		 r2 = 8;				\
 | |
| 		 r3 = 0;				\
 | |
| 		 r4 = r10;				\
 | |
| 		 r4 += -16;				\
 | |
| 		 call %[bpf_ringbuf_reserve_dynptr];	\
 | |
| 		 if r0 == 0 goto pjmp1;			\
 | |
| 		 goto pjmp2;				\
 | |
| 	pjmp1:						\
 | |
| 		 *(u64 *)(r10 - 16) = r9;		\
 | |
| 	pjmp2:						\
 | |
| 		 r1 = r10;				\
 | |
| 		 r1 += -16;				\
 | |
| 		 r2 = 0;				\
 | |
| 		 call %[bpf_ringbuf_discard_dynptr];	"
 | |
| 		:
 | |
| 		: __imm(bpf_ringbuf_reserve_dynptr),
 | |
| 		  __imm(bpf_ringbuf_discard_dynptr),
 | |
| 		  __imm_addr(ringbuf)
 | |
| 		: __clobber_all
 | |
| 	);
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| SEC("?tc")
 | |
| __success __msg("12: safe") __log_level(2)
 | |
| int dynptr_pruning_stacksafe(struct __sk_buff *ctx)
 | |
| {
 | |
| 	asm volatile (
 | |
| 		"r9 = 0xeB9F;				\
 | |
| 		 r6 = %[ringbuf] ll;			\
 | |
| 		 r1 = r6;				\
 | |
| 		 r2 = 8;				\
 | |
| 		 r3 = 0;				\
 | |
| 		 r4 = r10;				\
 | |
| 		 r4 += -16;				\
 | |
| 		 call %[bpf_ringbuf_reserve_dynptr];	\
 | |
| 		 if r0 == 0 goto stjmp1;		\
 | |
| 		 goto stjmp2;				\
 | |
| 	stjmp1:						\
 | |
| 		 r9 = r9;				\
 | |
| 	stjmp2:						\
 | |
| 		 r1 = r10;				\
 | |
| 		 r1 += -16;				\
 | |
| 		 r2 = 0;				\
 | |
| 		 call %[bpf_ringbuf_discard_dynptr];	"
 | |
| 		:
 | |
| 		: __imm(bpf_ringbuf_reserve_dynptr),
 | |
| 		  __imm(bpf_ringbuf_discard_dynptr),
 | |
| 		  __imm_addr(ringbuf)
 | |
| 		: __clobber_all
 | |
| 	);
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| SEC("?tc")
 | |
| __failure __msg("cannot overwrite referenced dynptr") __log_level(2)
 | |
| int dynptr_pruning_type_confusion(struct __sk_buff *ctx)
 | |
| {
 | |
| 	asm volatile (
 | |
| 		"r6 = %[array_map4] ll;			\
 | |
| 		 r7 = %[ringbuf] ll;			\
 | |
| 		 r1 = r6;				\
 | |
| 		 r2 = r10;				\
 | |
| 		 r2 += -8;				\
 | |
| 		 r9 = 0;				\
 | |
| 		 *(u64 *)(r2 + 0) = r9;			\
 | |
| 		 r3 = r10;				\
 | |
| 		 r3 += -24;				\
 | |
| 		 r9 = 0xeB9FeB9F;			\
 | |
| 		 *(u64 *)(r10 - 16) = r9;		\
 | |
| 		 *(u64 *)(r10 - 24) = r9;		\
 | |
| 		 r9 = 0;				\
 | |
| 		 r4 = 0;				\
 | |
| 		 r8 = r2;				\
 | |
| 		 call %[bpf_map_update_elem];		\
 | |
| 		 r1 = r6;				\
 | |
| 		 r2 = r8;				\
 | |
| 		 call %[bpf_map_lookup_elem];		\
 | |
| 		 if r0 != 0 goto tjmp1;			\
 | |
| 		 exit;					\
 | |
| 	tjmp1:						\
 | |
| 		 r8 = r0;				\
 | |
| 		 r1 = r7;				\
 | |
| 		 r2 = 8;				\
 | |
| 		 r3 = 0;				\
 | |
| 		 r4 = r10;				\
 | |
| 		 r4 += -16;				\
 | |
| 		 r0 = *(u64 *)(r0 + 0);			\
 | |
| 		 call %[bpf_ringbuf_reserve_dynptr];	\
 | |
| 		 if r0 == 0 goto tjmp2;			\
 | |
| 		 r8 = r8;				\
 | |
| 		 r8 = r8;				\
 | |
| 		 r8 = r8;				\
 | |
| 		 r8 = r8;				\
 | |
| 		 r8 = r8;				\
 | |
| 		 r8 = r8;				\
 | |
| 		 r8 = r8;				\
 | |
| 		 goto tjmp3;				\
 | |
| 	tjmp2:						\
 | |
| 		 *(u64 *)(r10 - 8) = r9;		\
 | |
| 		 *(u64 *)(r10 - 16) = r9;		\
 | |
| 		 r1 = r8;				\
 | |
| 		 r1 += 8;				\
 | |
| 		 r2 = 0;				\
 | |
| 		 r3 = 0;				\
 | |
| 		 r4 = r10;				\
 | |
| 		 r4 += -16;				\
 | |
| 		 call %[bpf_dynptr_from_mem];		\
 | |
| 	tjmp3:						\
 | |
| 		 r1 = r10;				\
 | |
| 		 r1 += -16;				\
 | |
| 		 r2 = 0;				\
 | |
| 		 call %[bpf_ringbuf_discard_dynptr];	"
 | |
| 		:
 | |
| 		: __imm(bpf_map_update_elem),
 | |
| 		  __imm(bpf_map_lookup_elem),
 | |
| 		  __imm(bpf_ringbuf_reserve_dynptr),
 | |
| 		  __imm(bpf_dynptr_from_mem),
 | |
| 		  __imm(bpf_ringbuf_discard_dynptr),
 | |
| 		  __imm_addr(array_map4),
 | |
| 		  __imm_addr(ringbuf)
 | |
| 		: __clobber_all
 | |
| 	);
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| SEC("?tc")
 | |
| __failure __msg("dynptr has to be at a constant offset") __log_level(2)
 | |
| int dynptr_var_off_overwrite(struct __sk_buff *ctx)
 | |
| {
 | |
| 	asm volatile (
 | |
| 		"r9 = 16;				\
 | |
| 		 *(u32 *)(r10 - 4) = r9;		\
 | |
| 		 r8 = *(u32 *)(r10 - 4);		\
 | |
| 		 if r8 >= 0 goto vjmp1;			\
 | |
| 		 r0 = 1;				\
 | |
| 		 exit;					\
 | |
| 	vjmp1:						\
 | |
| 		 if r8 <= 16 goto vjmp2;		\
 | |
| 		 r0 = 1;				\
 | |
| 		 exit;					\
 | |
| 	vjmp2:						\
 | |
| 		 r8 &= 16;				\
 | |
| 		 r1 = %[ringbuf] ll;			\
 | |
| 		 r2 = 8;				\
 | |
| 		 r3 = 0;				\
 | |
| 		 r4 = r10;				\
 | |
| 		 r4 += -32;				\
 | |
| 		 r4 += r8;				\
 | |
| 		 call %[bpf_ringbuf_reserve_dynptr];	\
 | |
| 		 r9 = 0xeB9F;				\
 | |
| 		 *(u64 *)(r10 - 16) = r9;		\
 | |
| 		 r1 = r10;				\
 | |
| 		 r1 += -32;				\
 | |
| 		 r1 += r8;				\
 | |
| 		 r2 = 0;				\
 | |
| 		 call %[bpf_ringbuf_discard_dynptr];	"
 | |
| 		:
 | |
| 		: __imm(bpf_ringbuf_reserve_dynptr),
 | |
| 		  __imm(bpf_ringbuf_discard_dynptr),
 | |
| 		  __imm_addr(ringbuf)
 | |
| 		: __clobber_all
 | |
| 	);
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| SEC("?tc")
 | |
| __failure __msg("cannot overwrite referenced dynptr") __log_level(2)
 | |
| int dynptr_partial_slot_invalidate(struct __sk_buff *ctx)
 | |
| {
 | |
| 	asm volatile (
 | |
| 		"r6 = %[ringbuf] ll;			\
 | |
| 		 r7 = %[array_map4] ll;			\
 | |
| 		 r1 = r7;				\
 | |
| 		 r2 = r10;				\
 | |
| 		 r2 += -8;				\
 | |
| 		 r9 = 0;				\
 | |
| 		 *(u64 *)(r2 + 0) = r9;			\
 | |
| 		 r3 = r2;				\
 | |
| 		 r4 = 0;				\
 | |
| 		 r8 = r2;				\
 | |
| 		 call %[bpf_map_update_elem];		\
 | |
| 		 r1 = r7;				\
 | |
| 		 r2 = r8;				\
 | |
| 		 call %[bpf_map_lookup_elem];		\
 | |
| 		 if r0 != 0 goto sjmp1;			\
 | |
| 		 exit;					\
 | |
| 	sjmp1:						\
 | |
| 		 r7 = r0;				\
 | |
| 		 r1 = r6;				\
 | |
| 		 r2 = 8;				\
 | |
| 		 r3 = 0;				\
 | |
| 		 r4 = r10;				\
 | |
| 		 r4 += -24;				\
 | |
| 		 call %[bpf_ringbuf_reserve_dynptr];	\
 | |
| 		 *(u64 *)(r10 - 16) = r9;		\
 | |
| 		 r1 = r7;				\
 | |
| 		 r2 = 8;				\
 | |
| 		 r3 = 0;				\
 | |
| 		 r4 = r10;				\
 | |
| 		 r4 += -16;				\
 | |
| 		 call %[bpf_dynptr_from_mem];		\
 | |
| 		 r1 = r10;				\
 | |
| 		 r1 += -512;				\
 | |
| 		 r2 = 488;				\
 | |
| 		 r3 = r10;				\
 | |
| 		 r3 += -24;				\
 | |
| 		 r4 = 0;				\
 | |
| 		 r5 = 0;				\
 | |
| 		 call %[bpf_dynptr_read];		\
 | |
| 		 r8 = 1;				\
 | |
| 		 if r0 != 0 goto sjmp2;			\
 | |
| 		 r8 = 0;				\
 | |
| 	sjmp2:						\
 | |
| 		 r1 = r10;				\
 | |
| 		 r1 += -24;				\
 | |
| 		 r2 = 0;				\
 | |
| 		 call %[bpf_ringbuf_discard_dynptr];	"
 | |
| 		:
 | |
| 		: __imm(bpf_map_update_elem),
 | |
| 		  __imm(bpf_map_lookup_elem),
 | |
| 		  __imm(bpf_ringbuf_reserve_dynptr),
 | |
| 		  __imm(bpf_ringbuf_discard_dynptr),
 | |
| 		  __imm(bpf_dynptr_from_mem),
 | |
| 		  __imm(bpf_dynptr_read),
 | |
| 		  __imm_addr(ringbuf),
 | |
| 		  __imm_addr(array_map4)
 | |
| 		: __clobber_all
 | |
| 	);
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /* Test that it is allowed to overwrite unreferenced dynptr. */
 | |
| SEC("?raw_tp")
 | |
| __success
 | |
| int dynptr_overwrite_unref(void *ctx)
 | |
| {
 | |
| 	struct bpf_dynptr ptr;
 | |
| 
 | |
| 	if (get_map_val_dynptr(&ptr))
 | |
| 		return 0;
 | |
| 	if (get_map_val_dynptr(&ptr))
 | |
| 		return 0;
 | |
| 	if (get_map_val_dynptr(&ptr))
 | |
| 		return 0;
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /* Test that slices are invalidated on reinitializing a dynptr. */
 | |
| SEC("?raw_tp")
 | |
| __failure __msg("invalid mem access 'scalar'")
 | |
| int dynptr_invalidate_slice_reinit(void *ctx)
 | |
| {
 | |
| 	struct bpf_dynptr ptr;
 | |
| 	__u8 *p;
 | |
| 
 | |
| 	if (get_map_val_dynptr(&ptr))
 | |
| 		return 0;
 | |
| 	p = bpf_dynptr_data(&ptr, 0, 1);
 | |
| 	if (!p)
 | |
| 		return 0;
 | |
| 	if (get_map_val_dynptr(&ptr))
 | |
| 		return 0;
 | |
| 	/* this should fail */
 | |
| 	return *p;
 | |
| }
 | |
| 
 | |
| /* Invalidation of dynptr slices on destruction of dynptr should not miss
 | |
|  * mem_or_null pointers.
 | |
|  */
 | |
| SEC("?raw_tp")
 | |
| __failure __regex("R[0-9]+ type=scalar expected=percpu_ptr_")
 | |
| int dynptr_invalidate_slice_or_null(void *ctx)
 | |
| {
 | |
| 	struct bpf_dynptr ptr;
 | |
| 	__u8 *p;
 | |
| 
 | |
| 	if (get_map_val_dynptr(&ptr))
 | |
| 		return 0;
 | |
| 
 | |
| 	p = bpf_dynptr_data(&ptr, 0, 1);
 | |
| 	*(__u8 *)&ptr = 0;
 | |
| 	/* this should fail */
 | |
| 	bpf_this_cpu_ptr(p);
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /* Destruction of dynptr should also any slices obtained from it */
 | |
| SEC("?raw_tp")
 | |
| __failure __regex("R[0-9]+ invalid mem access 'scalar'")
 | |
| int dynptr_invalidate_slice_failure(void *ctx)
 | |
| {
 | |
| 	struct bpf_dynptr ptr1;
 | |
| 	struct bpf_dynptr ptr2;
 | |
| 	__u8 *p1, *p2;
 | |
| 
 | |
| 	if (get_map_val_dynptr(&ptr1))
 | |
| 		return 0;
 | |
| 	if (get_map_val_dynptr(&ptr2))
 | |
| 		return 0;
 | |
| 
 | |
| 	p1 = bpf_dynptr_data(&ptr1, 0, 1);
 | |
| 	if (!p1)
 | |
| 		return 0;
 | |
| 	p2 = bpf_dynptr_data(&ptr2, 0, 1);
 | |
| 	if (!p2)
 | |
| 		return 0;
 | |
| 
 | |
| 	*(__u8 *)&ptr1 = 0;
 | |
| 	/* this should fail */
 | |
| 	return *p1;
 | |
| }
 | |
| 
 | |
| /* Invalidation of slices should be scoped and should not prevent dereferencing
 | |
|  * slices of another dynptr after destroying unrelated dynptr
 | |
|  */
 | |
| SEC("?raw_tp")
 | |
| __success
 | |
| int dynptr_invalidate_slice_success(void *ctx)
 | |
| {
 | |
| 	struct bpf_dynptr ptr1;
 | |
| 	struct bpf_dynptr ptr2;
 | |
| 	__u8 *p1, *p2;
 | |
| 
 | |
| 	if (get_map_val_dynptr(&ptr1))
 | |
| 		return 1;
 | |
| 	if (get_map_val_dynptr(&ptr2))
 | |
| 		return 1;
 | |
| 
 | |
| 	p1 = bpf_dynptr_data(&ptr1, 0, 1);
 | |
| 	if (!p1)
 | |
| 		return 1;
 | |
| 	p2 = bpf_dynptr_data(&ptr2, 0, 1);
 | |
| 	if (!p2)
 | |
| 		return 1;
 | |
| 
 | |
| 	*(__u8 *)&ptr1 = 0;
 | |
| 	return *p2;
 | |
| }
 | |
| 
 | |
| /* Overwriting referenced dynptr should be rejected */
 | |
| SEC("?raw_tp")
 | |
| __failure __msg("cannot overwrite referenced dynptr")
 | |
| int dynptr_overwrite_ref(void *ctx)
 | |
| {
 | |
| 	struct bpf_dynptr ptr;
 | |
| 
 | |
| 	bpf_ringbuf_reserve_dynptr(&ringbuf, 64, 0, &ptr);
 | |
| 	/* this should fail */
 | |
| 	if (get_map_val_dynptr(&ptr))
 | |
| 		bpf_ringbuf_discard_dynptr(&ptr, 0);
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /* Reject writes to dynptr slot from bpf_dynptr_read */
 | |
| SEC("?raw_tp")
 | |
| __failure __msg("potential write to dynptr at off=-16")
 | |
| int dynptr_read_into_slot(void *ctx)
 | |
| {
 | |
| 	union {
 | |
| 		struct {
 | |
| 			char _pad[48];
 | |
| 			struct bpf_dynptr ptr;
 | |
| 		};
 | |
| 		char buf[64];
 | |
| 	} data;
 | |
| 
 | |
| 	bpf_ringbuf_reserve_dynptr(&ringbuf, 64, 0, &data.ptr);
 | |
| 	/* this should fail */
 | |
| 	bpf_dynptr_read(data.buf, sizeof(data.buf), &data.ptr, 0, 0);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /* bpf_dynptr_slice()s are read-only and cannot be written to */
 | |
| SEC("?tc")
 | |
| __failure __regex("R[0-9]+ cannot write into rdonly_mem")
 | |
| int skb_invalid_slice_write(struct __sk_buff *skb)
 | |
| {
 | |
| 	struct bpf_dynptr ptr;
 | |
| 	struct ethhdr *hdr;
 | |
| 	char buffer[sizeof(*hdr)] = {};
 | |
| 
 | |
| 	bpf_dynptr_from_skb(skb, 0, &ptr);
 | |
| 
 | |
| 	hdr = bpf_dynptr_slice(&ptr, 0, buffer, sizeof(buffer));
 | |
| 	if (!hdr)
 | |
| 		return SK_DROP;
 | |
| 
 | |
| 	/* this should fail */
 | |
| 	hdr->h_proto = 1;
 | |
| 
 | |
| 	return SK_PASS;
 | |
| }
 | |
| 
 | |
| /* The read-only data slice is invalidated whenever a helper changes packet data */
 | |
| SEC("?tc")
 | |
| __failure __msg("invalid mem access 'scalar'")
 | |
| int skb_invalid_data_slice1(struct __sk_buff *skb)
 | |
| {
 | |
| 	struct bpf_dynptr ptr;
 | |
| 	struct ethhdr *hdr;
 | |
| 	char buffer[sizeof(*hdr)] = {};
 | |
| 
 | |
| 	bpf_dynptr_from_skb(skb, 0, &ptr);
 | |
| 
 | |
| 	hdr = bpf_dynptr_slice(&ptr, 0, buffer, sizeof(buffer));
 | |
| 	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-write data slice is invalidated whenever a helper changes packet data */
 | |
| SEC("?tc")
 | |
| __failure __msg("invalid mem access 'scalar'")
 | |
| int skb_invalid_data_slice2(struct __sk_buff *skb)
 | |
| {
 | |
| 	struct bpf_dynptr ptr;
 | |
| 	struct ethhdr *hdr;
 | |
| 	char buffer[sizeof(*hdr)] = {};
 | |
| 
 | |
| 	bpf_dynptr_from_skb(skb, 0, &ptr);
 | |
| 
 | |
| 	hdr = bpf_dynptr_slice_rdwr(&ptr, 0, buffer, sizeof(buffer));
 | |
| 	if (!hdr)
 | |
| 		return SK_DROP;
 | |
| 
 | |
| 	hdr->h_proto = 123;
 | |
| 
 | |
| 	if (bpf_skb_pull_data(skb, skb->len))
 | |
| 		return SK_DROP;
 | |
| 
 | |
| 	/* this should fail */
 | |
| 	hdr->h_proto = 1;
 | |
| 
 | |
| 	return SK_PASS;
 | |
| }
 | |
| 
 | |
| /* The read-only data slice is invalidated whenever bpf_dynptr_write() is called */
 | |
| SEC("?tc")
 | |
| __failure __msg("invalid mem access 'scalar'")
 | |
| int skb_invalid_data_slice3(struct __sk_buff *skb)
 | |
| {
 | |
| 	char write_data[64] = "hello there, world!!";
 | |
| 	struct bpf_dynptr ptr;
 | |
| 	struct ethhdr *hdr;
 | |
| 	char buffer[sizeof(*hdr)] = {};
 | |
| 
 | |
| 	bpf_dynptr_from_skb(skb, 0, &ptr);
 | |
| 
 | |
| 	hdr = bpf_dynptr_slice(&ptr, 0, buffer, sizeof(buffer));
 | |
| 	if (!hdr)
 | |
| 		return SK_DROP;
 | |
| 
 | |
| 	val = hdr->h_proto;
 | |
| 
 | |
| 	bpf_dynptr_write(&ptr, 0, write_data, sizeof(write_data), 0);
 | |
| 
 | |
| 	/* this should fail */
 | |
| 	val = hdr->h_proto;
 | |
| 
 | |
| 	return SK_PASS;
 | |
| }
 | |
| 
 | |
| /* The read-write data slice is invalidated whenever bpf_dynptr_write() is called */
 | |
| SEC("?tc")
 | |
| __failure __msg("invalid mem access 'scalar'")
 | |
| int skb_invalid_data_slice4(struct __sk_buff *skb)
 | |
| {
 | |
| 	char write_data[64] = "hello there, world!!";
 | |
| 	struct bpf_dynptr ptr;
 | |
| 	struct ethhdr *hdr;
 | |
| 	char buffer[sizeof(*hdr)] = {};
 | |
| 
 | |
| 	bpf_dynptr_from_skb(skb, 0, &ptr);
 | |
| 	hdr = bpf_dynptr_slice_rdwr(&ptr, 0, buffer, sizeof(buffer));
 | |
| 	if (!hdr)
 | |
| 		return SK_DROP;
 | |
| 
 | |
| 	hdr->h_proto = 123;
 | |
| 
 | |
| 	bpf_dynptr_write(&ptr, 0, write_data, sizeof(write_data), 0);
 | |
| 
 | |
| 	/* this should fail */
 | |
| 	hdr->h_proto = 1;
 | |
| 
 | |
| 	return SK_PASS;
 | |
| }
 | |
| 
 | |
| /* The read-only data slice is invalidated whenever a helper changes packet data */
 | |
| SEC("?xdp")
 | |
| __failure __msg("invalid mem access 'scalar'")
 | |
| int xdp_invalid_data_slice1(struct xdp_md *xdp)
 | |
| {
 | |
| 	struct bpf_dynptr ptr;
 | |
| 	struct ethhdr *hdr;
 | |
| 	char buffer[sizeof(*hdr)] = {};
 | |
| 
 | |
| 	bpf_dynptr_from_xdp(xdp, 0, &ptr);
 | |
| 	hdr = bpf_dynptr_slice(&ptr, 0, buffer, sizeof(buffer));
 | |
| 	if (!hdr)
 | |
| 		return SK_DROP;
 | |
| 
 | |
| 	val = hdr->h_proto;
 | |
| 
 | |
| 	if (bpf_xdp_adjust_head(xdp, 0 - (int)sizeof(*hdr)))
 | |
| 		return XDP_DROP;
 | |
| 
 | |
| 	/* this should fail */
 | |
| 	val = hdr->h_proto;
 | |
| 
 | |
| 	return XDP_PASS;
 | |
| }
 | |
| 
 | |
| /* The read-write data slice is invalidated whenever a helper changes packet data */
 | |
| SEC("?xdp")
 | |
| __failure __msg("invalid mem access 'scalar'")
 | |
| int xdp_invalid_data_slice2(struct xdp_md *xdp)
 | |
| {
 | |
| 	struct bpf_dynptr ptr;
 | |
| 	struct ethhdr *hdr;
 | |
| 	char buffer[sizeof(*hdr)] = {};
 | |
| 
 | |
| 	bpf_dynptr_from_xdp(xdp, 0, &ptr);
 | |
| 	hdr = bpf_dynptr_slice_rdwr(&ptr, 0, buffer, sizeof(buffer));
 | |
| 	if (!hdr)
 | |
| 		return SK_DROP;
 | |
| 
 | |
| 	hdr->h_proto = 9;
 | |
| 
 | |
| 	if (bpf_xdp_adjust_head(xdp, 0 - (int)sizeof(*hdr)))
 | |
| 		return XDP_DROP;
 | |
| 
 | |
| 	/* this should fail */
 | |
| 	hdr->h_proto = 1;
 | |
| 
 | |
| 	return XDP_PASS;
 | |
| }
 | |
| 
 | |
| /* Only supported prog type can create skb-type dynptrs */
 | |
| SEC("?raw_tp")
 | |
| __failure __msg("calling kernel function bpf_dynptr_from_skb is not allowed")
 | |
| int skb_invalid_ctx(void *ctx)
 | |
| {
 | |
| 	struct bpf_dynptr ptr;
 | |
| 
 | |
| 	/* this should fail */
 | |
| 	bpf_dynptr_from_skb(ctx, 0, &ptr);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| SEC("fentry/skb_tx_error")
 | |
| __failure __msg("must be referenced or trusted")
 | |
| int BPF_PROG(skb_invalid_ctx_fentry, void *skb)
 | |
| {
 | |
| 	struct bpf_dynptr ptr;
 | |
| 
 | |
| 	/* this should fail */
 | |
| 	bpf_dynptr_from_skb(skb, 0, &ptr);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| SEC("fexit/skb_tx_error")
 | |
| __failure __msg("must be referenced or trusted")
 | |
| int BPF_PROG(skb_invalid_ctx_fexit, void *skb)
 | |
| {
 | |
| 	struct bpf_dynptr ptr;
 | |
| 
 | |
| 	/* this should fail */
 | |
| 	bpf_dynptr_from_skb(skb, 0, &ptr);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /* Reject writes to dynptr slot for uninit arg */
 | |
| SEC("?raw_tp")
 | |
| __failure __msg("potential write to dynptr at off=-16")
 | |
| int uninit_write_into_slot(void *ctx)
 | |
| {
 | |
| 	struct {
 | |
| 		char buf[64];
 | |
| 		struct bpf_dynptr ptr;
 | |
| 	} data;
 | |
| 
 | |
| 	bpf_ringbuf_reserve_dynptr(&ringbuf, 80, 0, &data.ptr);
 | |
| 	/* this should fail */
 | |
| 	bpf_get_current_comm(data.buf, 80);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /* Only supported prog type can create xdp-type dynptrs */
 | |
| SEC("?raw_tp")
 | |
| __failure __msg("calling kernel function bpf_dynptr_from_xdp is not allowed")
 | |
| int xdp_invalid_ctx(void *ctx)
 | |
| {
 | |
| 	struct bpf_dynptr ptr;
 | |
| 
 | |
| 	/* this should fail */
 | |
| 	bpf_dynptr_from_xdp(ctx, 0, &ptr);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| __u32 hdr_size = sizeof(struct ethhdr);
 | |
| /* Can't pass in variable-sized len to bpf_dynptr_slice */
 | |
| SEC("?tc")
 | |
| __failure __msg("unbounded memory access")
 | |
| int dynptr_slice_var_len1(struct __sk_buff *skb)
 | |
| {
 | |
| 	struct bpf_dynptr ptr;
 | |
| 	struct ethhdr *hdr;
 | |
| 	char buffer[sizeof(*hdr)] = {};
 | |
| 
 | |
| 	bpf_dynptr_from_skb(skb, 0, &ptr);
 | |
| 
 | |
| 	/* this should fail */
 | |
| 	hdr = bpf_dynptr_slice(&ptr, 0, buffer, hdr_size);
 | |
| 	if (!hdr)
 | |
| 		return SK_DROP;
 | |
| 
 | |
| 	return SK_PASS;
 | |
| }
 | |
| 
 | |
| /* Can't pass in variable-sized len to bpf_dynptr_slice */
 | |
| SEC("?tc")
 | |
| __failure __msg("must be a known constant")
 | |
| int dynptr_slice_var_len2(struct __sk_buff *skb)
 | |
| {
 | |
| 	char buffer[sizeof(struct ethhdr)] = {};
 | |
| 	struct bpf_dynptr ptr;
 | |
| 	struct ethhdr *hdr;
 | |
| 
 | |
| 	bpf_dynptr_from_skb(skb, 0, &ptr);
 | |
| 
 | |
| 	if (hdr_size <= sizeof(buffer)) {
 | |
| 		/* this should fail */
 | |
| 		hdr = bpf_dynptr_slice_rdwr(&ptr, 0, buffer, hdr_size);
 | |
| 		if (!hdr)
 | |
| 			return SK_DROP;
 | |
| 		hdr->h_proto = 12;
 | |
| 	}
 | |
| 
 | |
| 	return SK_PASS;
 | |
| }
 | |
| 
 | |
| static int callback(__u32 index, void *data)
 | |
| {
 | |
|         *(__u32 *)data = 123;
 | |
| 
 | |
|         return 0;
 | |
| }
 | |
| 
 | |
| /* If the dynptr is written into in a callback function, its data
 | |
|  * slices should be invalidated as well.
 | |
|  */
 | |
| SEC("?raw_tp")
 | |
| __failure __msg("invalid mem access 'scalar'")
 | |
| int invalid_data_slices(void *ctx)
 | |
| {
 | |
| 	struct bpf_dynptr ptr;
 | |
| 	__u32 *slice;
 | |
| 
 | |
| 	if (get_map_val_dynptr(&ptr))
 | |
| 		return 0;
 | |
| 
 | |
| 	slice = bpf_dynptr_data(&ptr, 0, sizeof(__u32));
 | |
| 	if (!slice)
 | |
| 		return 0;
 | |
| 
 | |
| 	bpf_loop(10, callback, &ptr, 0);
 | |
| 
 | |
| 	/* this should fail */
 | |
| 	*slice = 1;
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /* Program types that don't allow writes to packet data should fail if
 | |
|  * bpf_dynptr_slice_rdwr is called
 | |
|  */
 | |
| SEC("cgroup_skb/ingress")
 | |
| __failure __msg("the prog does not allow writes to packet data")
 | |
| int invalid_slice_rdwr_rdonly(struct __sk_buff *skb)
 | |
| {
 | |
| 	char buffer[sizeof(struct ethhdr)] = {};
 | |
| 	struct bpf_dynptr ptr;
 | |
| 	struct ethhdr *hdr;
 | |
| 
 | |
| 	bpf_dynptr_from_skb(skb, 0, &ptr);
 | |
| 
 | |
| 	/* this should fail since cgroup_skb doesn't allow
 | |
| 	 * changing packet data
 | |
| 	 */
 | |
| 	hdr = bpf_dynptr_slice_rdwr(&ptr, 0, buffer, sizeof(buffer));
 | |
| 	__sink(hdr);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /* bpf_dynptr_adjust can only be called on initialized dynptrs */
 | |
| SEC("?raw_tp")
 | |
| __failure __msg("Expected an initialized dynptr as arg #1")
 | |
| int dynptr_adjust_invalid(void *ctx)
 | |
| {
 | |
| 	struct bpf_dynptr ptr = {};
 | |
| 
 | |
| 	/* this should fail */
 | |
| 	bpf_dynptr_adjust(&ptr, 1, 2);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /* bpf_dynptr_is_null can only be called on initialized dynptrs */
 | |
| SEC("?raw_tp")
 | |
| __failure __msg("Expected an initialized dynptr as arg #1")
 | |
| int dynptr_is_null_invalid(void *ctx)
 | |
| {
 | |
| 	struct bpf_dynptr ptr = {};
 | |
| 
 | |
| 	/* this should fail */
 | |
| 	bpf_dynptr_is_null(&ptr);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /* bpf_dynptr_is_rdonly can only be called on initialized dynptrs */
 | |
| SEC("?raw_tp")
 | |
| __failure __msg("Expected an initialized dynptr as arg #1")
 | |
| int dynptr_is_rdonly_invalid(void *ctx)
 | |
| {
 | |
| 	struct bpf_dynptr ptr = {};
 | |
| 
 | |
| 	/* this should fail */
 | |
| 	bpf_dynptr_is_rdonly(&ptr);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /* bpf_dynptr_size can only be called on initialized dynptrs */
 | |
| SEC("?raw_tp")
 | |
| __failure __msg("Expected an initialized dynptr as arg #1")
 | |
| int dynptr_size_invalid(void *ctx)
 | |
| {
 | |
| 	struct bpf_dynptr ptr = {};
 | |
| 
 | |
| 	/* this should fail */
 | |
| 	bpf_dynptr_size(&ptr);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /* Only initialized dynptrs can be cloned */
 | |
| SEC("?raw_tp")
 | |
| __failure __msg("Expected an initialized dynptr as arg #1")
 | |
| int clone_invalid1(void *ctx)
 | |
| {
 | |
| 	struct bpf_dynptr ptr1 = {};
 | |
| 	struct bpf_dynptr ptr2;
 | |
| 
 | |
| 	/* this should fail */
 | |
| 	bpf_dynptr_clone(&ptr1, &ptr2);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| /* Can't overwrite an existing dynptr when cloning */
 | |
| SEC("?xdp")
 | |
| __failure __msg("cannot overwrite referenced dynptr")
 | |
| 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")
 | |
| __failure __msg("Expected an initialized dynptr as arg #3")
 | |
| 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")
 | |
| __failure __msg("Expected an initialized dynptr as arg #3")
 | |
| 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")
 | |
| __failure __msg("Expected an initialized dynptr as arg #3")
 | |
| 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")
 | |
| __failure __msg("invalid mem access 'scalar'")
 | |
| 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")
 | |
| __failure __msg("invalid mem access 'scalar'")
 | |
| 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")
 | |
| __failure __msg("invalid mem access 'scalar'")
 | |
| 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")
 | |
| __failure __msg("invalid mem access 'scalar'")
 | |
| int clone_skb_packet_data(struct __sk_buff *skb)
 | |
| {
 | |
| 	char buffer[sizeof(__u32)] = {};
 | |
| 	struct bpf_dynptr clone;
 | |
| 	struct bpf_dynptr ptr;
 | |
| 	__u32 *data;
 | |
| 
 | |
| 	bpf_dynptr_from_skb(skb, 0, &ptr);
 | |
| 
 | |
| 	bpf_dynptr_clone(&ptr, &clone);
 | |
| 	data = bpf_dynptr_slice_rdwr(&clone, 0, buffer, sizeof(buffer));
 | |
| 	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")
 | |
| __failure __msg("invalid mem access 'scalar'")
 | |
| int clone_xdp_packet_data(struct xdp_md *xdp)
 | |
| {
 | |
| 	char buffer[sizeof(__u32)] = {};
 | |
| 	struct bpf_dynptr clone;
 | |
| 	struct bpf_dynptr ptr;
 | |
| 	struct ethhdr *hdr;
 | |
| 	__u32 *data;
 | |
| 
 | |
| 	bpf_dynptr_from_xdp(xdp, 0, &ptr);
 | |
| 
 | |
| 	bpf_dynptr_clone(&ptr, &clone);
 | |
| 	data = bpf_dynptr_slice_rdwr(&clone, 0, buffer, sizeof(buffer));
 | |
| 	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;
 | |
| }
 | |
| 
 | |
| /* Buffers that are provided must be sufficiently long */
 | |
| SEC("?cgroup_skb/egress")
 | |
| __failure __msg("memory, len pair leads to invalid memory access")
 | |
| int test_dynptr_skb_small_buff(struct __sk_buff *skb)
 | |
| {
 | |
| 	struct bpf_dynptr ptr;
 | |
| 	char buffer[8] = {};
 | |
| 	__u64 *data;
 | |
| 
 | |
| 	if (bpf_dynptr_from_skb(skb, 0, &ptr)) {
 | |
| 		err = 1;
 | |
| 		return 1;
 | |
| 	}
 | |
| 
 | |
| 	/* This may return NULL. SKB may require a buffer */
 | |
| 	data = bpf_dynptr_slice(&ptr, 0, buffer, 9);
 | |
| 
 | |
| 	return !!data;
 | |
| }
 | |
| 
 | |
| __noinline long global_call_bpf_dynptr(const struct bpf_dynptr *dynptr)
 | |
| {
 | |
| 	long ret = 0;
 | |
| 	/* Avoid leaving this global function empty to avoid having the compiler
 | |
| 	 * optimize away the call to this global function.
 | |
| 	 */
 | |
| 	__sink(ret);
 | |
| 	return ret;
 | |
| }
 | |
| 
 | |
| SEC("?raw_tp")
 | |
| __failure __msg("arg#1 expected pointer to stack or const struct bpf_dynptr")
 | |
| int test_dynptr_reg_type(void *ctx)
 | |
| {
 | |
| 	struct task_struct *current = NULL;
 | |
| 	/* R1 should be holding a PTR_TO_BTF_ID, so this shouldn't be a
 | |
| 	 * reg->type that can be passed to a function accepting a
 | |
| 	 * ARG_PTR_TO_DYNPTR | MEM_RDONLY. process_dynptr_func() should catch
 | |
| 	 * this.
 | |
| 	 */
 | |
| 	global_call_bpf_dynptr((const struct bpf_dynptr *)current);
 | |
| 	return 0;
 | |
| }
 |