xref: /linux/tools/testing/selftests/bpf/prog_tests/reg_bounds.c (revision 3a39d672e7f48b8d6b91a09afa4b55352773b4b5)
1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (c) 2023 Meta Platforms, Inc. and affiliates. */
3 
4 #define _GNU_SOURCE
5 #include <limits.h>
6 #include <test_progs.h>
7 #include <linux/filter.h>
8 #include <linux/bpf.h>
9 
10 /* =================================
11  * SHORT AND CONSISTENT NUMBER TYPES
12  * =================================
13  */
14 #define U64_MAX ((u64)UINT64_MAX)
15 #define U32_MAX ((u32)UINT_MAX)
16 #define U16_MAX ((u32)UINT_MAX)
17 #define S64_MIN ((s64)INT64_MIN)
18 #define S64_MAX ((s64)INT64_MAX)
19 #define S32_MIN ((s32)INT_MIN)
20 #define S32_MAX ((s32)INT_MAX)
21 #define S16_MIN ((s16)0x80000000)
22 #define S16_MAX ((s16)0x7fffffff)
23 
24 typedef unsigned long long ___u64;
25 typedef unsigned int ___u32;
26 typedef long long ___s64;
27 typedef int ___s32;
28 
29 /* avoid conflicts with already defined types in kernel headers */
30 #define u64 ___u64
31 #define u32 ___u32
32 #define s64 ___s64
33 #define s32 ___s32
34 
35 /* ==================================
36  * STRING BUF ABSTRACTION AND HELPERS
37  * ==================================
38  */
39 struct strbuf {
40 	size_t buf_sz;
41 	int pos;
42 	char buf[0];
43 };
44 
45 #define DEFINE_STRBUF(name, N)						\
46 	struct { struct strbuf buf; char data[(N)]; } ___##name;	\
47 	struct strbuf *name = (___##name.buf.buf_sz = (N), ___##name.buf.pos = 0, &___##name.buf)
48 
49 __printf(2, 3)
snappendf(struct strbuf * s,const char * fmt,...)50 static inline void snappendf(struct strbuf *s, const char *fmt, ...)
51 {
52 	va_list args;
53 
54 	va_start(args, fmt);
55 	s->pos += vsnprintf(s->buf + s->pos,
56 			    s->pos < s->buf_sz ? s->buf_sz - s->pos : 0,
57 			    fmt, args);
58 	va_end(args);
59 }
60 
61 /* ==================================
62  * GENERIC NUMBER TYPE AND OPERATIONS
63  * ==================================
64  */
65 enum num_t { U64, first_t = U64, U32, S64, S32, last_t = S32 };
66 
min_t(enum num_t t,u64 x,u64 y)67 static __always_inline u64 min_t(enum num_t t, u64 x, u64 y)
68 {
69 	switch (t) {
70 	case U64: return (u64)x < (u64)y ? (u64)x : (u64)y;
71 	case U32: return (u32)x < (u32)y ? (u32)x : (u32)y;
72 	case S64: return (s64)x < (s64)y ? (s64)x : (s64)y;
73 	case S32: return (s32)x < (s32)y ? (s32)x : (s32)y;
74 	default: printf("min_t!\n"); exit(1);
75 	}
76 }
77 
max_t(enum num_t t,u64 x,u64 y)78 static __always_inline u64 max_t(enum num_t t, u64 x, u64 y)
79 {
80 	switch (t) {
81 	case U64: return (u64)x > (u64)y ? (u64)x : (u64)y;
82 	case U32: return (u32)x > (u32)y ? (u32)x : (u32)y;
83 	case S64: return (s64)x > (s64)y ? (s64)x : (s64)y;
84 	case S32: return (s32)x > (s32)y ? (u32)(s32)x : (u32)(s32)y;
85 	default: printf("max_t!\n"); exit(1);
86 	}
87 }
88 
cast_t(enum num_t t,u64 x)89 static __always_inline u64 cast_t(enum num_t t, u64 x)
90 {
91 	switch (t) {
92 	case U64: return (u64)x;
93 	case U32: return (u32)x;
94 	case S64: return (s64)x;
95 	case S32: return (u32)(s32)x;
96 	default: printf("cast_t!\n"); exit(1);
97 	}
98 }
99 
t_str(enum num_t t)100 static const char *t_str(enum num_t t)
101 {
102 	switch (t) {
103 	case U64: return "u64";
104 	case U32: return "u32";
105 	case S64: return "s64";
106 	case S32: return "s32";
107 	default: printf("t_str!\n"); exit(1);
108 	}
109 }
110 
t_is_32(enum num_t t)111 static enum num_t t_is_32(enum num_t t)
112 {
113 	switch (t) {
114 	case U64: return false;
115 	case U32: return true;
116 	case S64: return false;
117 	case S32: return true;
118 	default: printf("t_is_32!\n"); exit(1);
119 	}
120 }
121 
t_signed(enum num_t t)122 static enum num_t t_signed(enum num_t t)
123 {
124 	switch (t) {
125 	case U64: return S64;
126 	case U32: return S32;
127 	case S64: return S64;
128 	case S32: return S32;
129 	default: printf("t_signed!\n"); exit(1);
130 	}
131 }
132 
t_unsigned(enum num_t t)133 static enum num_t t_unsigned(enum num_t t)
134 {
135 	switch (t) {
136 	case U64: return U64;
137 	case U32: return U32;
138 	case S64: return U64;
139 	case S32: return U32;
140 	default: printf("t_unsigned!\n"); exit(1);
141 	}
142 }
143 
144 #define UNUM_MAX_DECIMAL U16_MAX
145 #define SNUM_MAX_DECIMAL S16_MAX
146 #define SNUM_MIN_DECIMAL S16_MIN
147 
num_is_small(enum num_t t,u64 x)148 static bool num_is_small(enum num_t t, u64 x)
149 {
150 	switch (t) {
151 	case U64: return (u64)x <= UNUM_MAX_DECIMAL;
152 	case U32: return (u32)x <= UNUM_MAX_DECIMAL;
153 	case S64: return (s64)x >= SNUM_MIN_DECIMAL && (s64)x <= SNUM_MAX_DECIMAL;
154 	case S32: return (s32)x >= SNUM_MIN_DECIMAL && (s32)x <= SNUM_MAX_DECIMAL;
155 	default: printf("num_is_small!\n"); exit(1);
156 	}
157 }
158 
snprintf_num(enum num_t t,struct strbuf * sb,u64 x)159 static void snprintf_num(enum num_t t, struct strbuf *sb, u64 x)
160 {
161 	bool is_small = num_is_small(t, x);
162 
163 	if (is_small) {
164 		switch (t) {
165 		case U64: return snappendf(sb, "%llu", (u64)x);
166 		case U32: return snappendf(sb, "%u", (u32)x);
167 		case S64: return snappendf(sb, "%lld", (s64)x);
168 		case S32: return snappendf(sb, "%d", (s32)x);
169 		default: printf("snprintf_num!\n"); exit(1);
170 		}
171 	} else {
172 		switch (t) {
173 		case U64:
174 			if (x == U64_MAX)
175 				return snappendf(sb, "U64_MAX");
176 			else if (x >= U64_MAX - 256)
177 				return snappendf(sb, "U64_MAX-%llu", U64_MAX - x);
178 			else
179 				return snappendf(sb, "%#llx", (u64)x);
180 		case U32:
181 			if ((u32)x == U32_MAX)
182 				return snappendf(sb, "U32_MAX");
183 			else if ((u32)x >= U32_MAX - 256)
184 				return snappendf(sb, "U32_MAX-%u", U32_MAX - (u32)x);
185 			else
186 				return snappendf(sb, "%#x", (u32)x);
187 		case S64:
188 			if ((s64)x == S64_MAX)
189 				return snappendf(sb, "S64_MAX");
190 			else if ((s64)x >= S64_MAX - 256)
191 				return snappendf(sb, "S64_MAX-%lld", S64_MAX - (s64)x);
192 			else if ((s64)x == S64_MIN)
193 				return snappendf(sb, "S64_MIN");
194 			else if ((s64)x <= S64_MIN + 256)
195 				return snappendf(sb, "S64_MIN+%lld", (s64)x - S64_MIN);
196 			else
197 				return snappendf(sb, "%#llx", (s64)x);
198 		case S32:
199 			if ((s32)x == S32_MAX)
200 				return snappendf(sb, "S32_MAX");
201 			else if ((s32)x >= S32_MAX - 256)
202 				return snappendf(sb, "S32_MAX-%d", S32_MAX - (s32)x);
203 			else if ((s32)x == S32_MIN)
204 				return snappendf(sb, "S32_MIN");
205 			else if ((s32)x <= S32_MIN + 256)
206 				return snappendf(sb, "S32_MIN+%d", (s32)x - S32_MIN);
207 			else
208 				return snappendf(sb, "%#x", (s32)x);
209 		default: printf("snprintf_num!\n"); exit(1);
210 		}
211 	}
212 }
213 
214 /* ===================================
215  * GENERIC RANGE STRUCT AND OPERATIONS
216  * ===================================
217  */
218 struct range {
219 	u64 a, b;
220 };
221 
snprintf_range(enum num_t t,struct strbuf * sb,struct range x)222 static void snprintf_range(enum num_t t, struct strbuf *sb, struct range x)
223 {
224 	if (x.a == x.b)
225 		return snprintf_num(t, sb, x.a);
226 
227 	snappendf(sb, "[");
228 	snprintf_num(t, sb, x.a);
229 	snappendf(sb, "; ");
230 	snprintf_num(t, sb, x.b);
231 	snappendf(sb, "]");
232 }
233 
print_range(enum num_t t,struct range x,const char * sfx)234 static void print_range(enum num_t t, struct range x, const char *sfx)
235 {
236 	DEFINE_STRBUF(sb, 128);
237 
238 	snprintf_range(t, sb, x);
239 	printf("%s%s", sb->buf, sfx);
240 }
241 
242 static const struct range unkn[] = {
243 	[U64] = { 0, U64_MAX },
244 	[U32] = { 0, U32_MAX },
245 	[S64] = { (u64)S64_MIN, (u64)S64_MAX },
246 	[S32] = { (u64)(u32)S32_MIN, (u64)(u32)S32_MAX },
247 };
248 
unkn_subreg(enum num_t t)249 static struct range unkn_subreg(enum num_t t)
250 {
251 	switch (t) {
252 	case U64: return unkn[U32];
253 	case U32: return unkn[U32];
254 	case S64: return unkn[U32];
255 	case S32: return unkn[S32];
256 	default: printf("unkn_subreg!\n"); exit(1);
257 	}
258 }
259 
range(enum num_t t,u64 a,u64 b)260 static struct range range(enum num_t t, u64 a, u64 b)
261 {
262 	switch (t) {
263 	case U64: return (struct range){ (u64)a, (u64)b };
264 	case U32: return (struct range){ (u32)a, (u32)b };
265 	case S64: return (struct range){ (s64)a, (s64)b };
266 	case S32: return (struct range){ (u32)(s32)a, (u32)(s32)b };
267 	default: printf("range!\n"); exit(1);
268 	}
269 }
270 
sign64(u64 x)271 static __always_inline u32 sign64(u64 x) { return (x >> 63) & 1; }
sign32(u64 x)272 static __always_inline u32 sign32(u64 x) { return ((u32)x >> 31) & 1; }
upper32(u64 x)273 static __always_inline u32 upper32(u64 x) { return (u32)(x >> 32); }
swap_low32(u64 x,u32 y)274 static __always_inline u64 swap_low32(u64 x, u32 y) { return (x & 0xffffffff00000000ULL) | y; }
275 
range_eq(struct range x,struct range y)276 static bool range_eq(struct range x, struct range y)
277 {
278 	return x.a == y.a && x.b == y.b;
279 }
280 
range_cast_to_s32(struct range x)281 static struct range range_cast_to_s32(struct range x)
282 {
283 	u64 a = x.a, b = x.b;
284 
285 	/* if upper 32 bits are constant, lower 32 bits should form a proper
286 	 * s32 range to be correct
287 	 */
288 	if (upper32(a) == upper32(b) && (s32)a <= (s32)b)
289 		return range(S32, a, b);
290 
291 	/* Special case where upper bits form a small sequence of two
292 	 * sequential numbers (in 32-bit unsigned space, so 0xffffffff to
293 	 * 0x00000000 is also valid), while lower bits form a proper s32 range
294 	 * going from negative numbers to positive numbers.
295 	 *
296 	 * E.g.: [0xfffffff0ffffff00; 0xfffffff100000010]. Iterating
297 	 * over full 64-bit numbers range will form a proper [-16, 16]
298 	 * ([0xffffff00; 0x00000010]) range in its lower 32 bits.
299 	 */
300 	if (upper32(a) + 1 == upper32(b) && (s32)a < 0 && (s32)b >= 0)
301 		return range(S32, a, b);
302 
303 	/* otherwise we can't derive much meaningful information */
304 	return unkn[S32];
305 }
306 
range_cast_u64(enum num_t to_t,struct range x)307 static struct range range_cast_u64(enum num_t to_t, struct range x)
308 {
309 	u64 a = (u64)x.a, b = (u64)x.b;
310 
311 	switch (to_t) {
312 	case U64:
313 		return x;
314 	case U32:
315 		if (upper32(a) != upper32(b))
316 			return unkn[U32];
317 		return range(U32, a, b);
318 	case S64:
319 		if (sign64(a) != sign64(b))
320 			return unkn[S64];
321 		return range(S64, a, b);
322 	case S32:
323 		return range_cast_to_s32(x);
324 	default: printf("range_cast_u64!\n"); exit(1);
325 	}
326 }
327 
range_cast_s64(enum num_t to_t,struct range x)328 static struct range range_cast_s64(enum num_t to_t, struct range x)
329 {
330 	s64 a = (s64)x.a, b = (s64)x.b;
331 
332 	switch (to_t) {
333 	case U64:
334 		/* equivalent to (s64)a <= (s64)b check */
335 		if (sign64(a) != sign64(b))
336 			return unkn[U64];
337 		return range(U64, a, b);
338 	case U32:
339 		if (upper32(a) != upper32(b) || sign32(a) != sign32(b))
340 			return unkn[U32];
341 		return range(U32, a, b);
342 	case S64:
343 		return x;
344 	case S32:
345 		return range_cast_to_s32(x);
346 	default: printf("range_cast_s64!\n"); exit(1);
347 	}
348 }
349 
range_cast_u32(enum num_t to_t,struct range x)350 static struct range range_cast_u32(enum num_t to_t, struct range x)
351 {
352 	u32 a = (u32)x.a, b = (u32)x.b;
353 
354 	switch (to_t) {
355 	case U64:
356 	case S64:
357 		/* u32 is always a valid zero-extended u64/s64 */
358 		return range(to_t, a, b);
359 	case U32:
360 		return x;
361 	case S32:
362 		return range_cast_to_s32(range(U32, a, b));
363 	default: printf("range_cast_u32!\n"); exit(1);
364 	}
365 }
366 
range_cast_s32(enum num_t to_t,struct range x)367 static struct range range_cast_s32(enum num_t to_t, struct range x)
368 {
369 	s32 a = (s32)x.a, b = (s32)x.b;
370 
371 	switch (to_t) {
372 	case U64:
373 	case U32:
374 	case S64:
375 		if (sign32(a) != sign32(b))
376 			return unkn[to_t];
377 		return range(to_t, a, b);
378 	case S32:
379 		return x;
380 	default: printf("range_cast_s32!\n"); exit(1);
381 	}
382 }
383 
384 /* Reinterpret range in *from_t* domain as a range in *to_t* domain preserving
385  * all possible information. Worst case, it will be unknown range within
386  * *to_t* domain, if nothing more specific can be guaranteed during the
387  * conversion
388  */
range_cast(enum num_t from_t,enum num_t to_t,struct range from)389 static struct range range_cast(enum num_t from_t, enum num_t to_t, struct range from)
390 {
391 	switch (from_t) {
392 	case U64: return range_cast_u64(to_t, from);
393 	case U32: return range_cast_u32(to_t, from);
394 	case S64: return range_cast_s64(to_t, from);
395 	case S32: return range_cast_s32(to_t, from);
396 	default: printf("range_cast!\n"); exit(1);
397 	}
398 }
399 
is_valid_num(enum num_t t,u64 x)400 static bool is_valid_num(enum num_t t, u64 x)
401 {
402 	switch (t) {
403 	case U64: return true;
404 	case U32: return upper32(x) == 0;
405 	case S64: return true;
406 	case S32: return upper32(x) == 0;
407 	default: printf("is_valid_num!\n"); exit(1);
408 	}
409 }
410 
is_valid_range(enum num_t t,struct range x)411 static bool is_valid_range(enum num_t t, struct range x)
412 {
413 	if (!is_valid_num(t, x.a) || !is_valid_num(t, x.b))
414 		return false;
415 
416 	switch (t) {
417 	case U64: return (u64)x.a <= (u64)x.b;
418 	case U32: return (u32)x.a <= (u32)x.b;
419 	case S64: return (s64)x.a <= (s64)x.b;
420 	case S32: return (s32)x.a <= (s32)x.b;
421 	default: printf("is_valid_range!\n"); exit(1);
422 	}
423 }
424 
range_improve(enum num_t t,struct range old,struct range new)425 static struct range range_improve(enum num_t t, struct range old, struct range new)
426 {
427 	return range(t, max_t(t, old.a, new.a), min_t(t, old.b, new.b));
428 }
429 
range_refine(enum num_t x_t,struct range x,enum num_t y_t,struct range y)430 static struct range range_refine(enum num_t x_t, struct range x, enum num_t y_t, struct range y)
431 {
432 	struct range y_cast;
433 
434 	y_cast = range_cast(y_t, x_t, y);
435 
436 	/* If we know that
437 	 *   - *x* is in the range of signed 32bit value, and
438 	 *   - *y_cast* range is 32-bit signed non-negative
439 	 * then *x* range can be improved with *y_cast* such that *x* range
440 	 * is 32-bit signed non-negative. Otherwise, if the new range for *x*
441 	 * allows upper 32-bit * 0xffffffff then the eventual new range for
442 	 * *x* will be out of signed 32-bit range which violates the origin
443 	 * *x* range.
444 	 */
445 	if (x_t == S64 && y_t == S32 && y_cast.a <= S32_MAX  && y_cast.b <= S32_MAX &&
446 	    (s64)x.a >= S32_MIN && (s64)x.b <= S32_MAX)
447 		return range_improve(x_t, x, y_cast);
448 
449 	/* the case when new range knowledge, *y*, is a 32-bit subregister
450 	 * range, while previous range knowledge, *x*, is a full register
451 	 * 64-bit range, needs special treatment to take into account upper 32
452 	 * bits of full register range
453 	 */
454 	if (t_is_32(y_t) && !t_is_32(x_t)) {
455 		struct range x_swap;
456 
457 		/* some combinations of upper 32 bits and sign bit can lead to
458 		 * invalid ranges, in such cases it's easier to detect them
459 		 * after cast/swap than try to enumerate all the conditions
460 		 * under which transformation and knowledge transfer is valid
461 		 */
462 		x_swap = range(x_t, swap_low32(x.a, y_cast.a), swap_low32(x.b, y_cast.b));
463 		if (!is_valid_range(x_t, x_swap))
464 			return x;
465 		return range_improve(x_t, x, x_swap);
466 	}
467 
468 	/* otherwise, plain range cast and intersection works */
469 	return range_improve(x_t, x, y_cast);
470 }
471 
472 /* =======================
473  * GENERIC CONDITIONAL OPS
474  * =======================
475  */
476 enum op { OP_LT, OP_LE, OP_GT, OP_GE, OP_EQ, OP_NE, first_op = OP_LT, last_op = OP_NE };
477 
complement_op(enum op op)478 static enum op complement_op(enum op op)
479 {
480 	switch (op) {
481 	case OP_LT: return OP_GE;
482 	case OP_LE: return OP_GT;
483 	case OP_GT: return OP_LE;
484 	case OP_GE: return OP_LT;
485 	case OP_EQ: return OP_NE;
486 	case OP_NE: return OP_EQ;
487 	default: printf("complement_op!\n"); exit(1);
488 	}
489 }
490 
op_str(enum op op)491 static const char *op_str(enum op op)
492 {
493 	switch (op) {
494 	case OP_LT: return "<";
495 	case OP_LE: return "<=";
496 	case OP_GT: return ">";
497 	case OP_GE: return ">=";
498 	case OP_EQ: return "==";
499 	case OP_NE: return "!=";
500 	default: printf("op_str!\n"); exit(1);
501 	}
502 }
503 
504 /* Can register with range [x.a, x.b] *EVER* satisfy
505  * OP (<, <=, >, >=, ==, !=) relation to
506  * a register with range [y.a, y.b]
507  * _in *num_t* domain_
508  */
range_canbe_op(enum num_t t,struct range x,struct range y,enum op op)509 static bool range_canbe_op(enum num_t t, struct range x, struct range y, enum op op)
510 {
511 #define range_canbe(T) do {									\
512 	switch (op) {										\
513 	case OP_LT: return (T)x.a < (T)y.b;							\
514 	case OP_LE: return (T)x.a <= (T)y.b;							\
515 	case OP_GT: return (T)x.b > (T)y.a;							\
516 	case OP_GE: return (T)x.b >= (T)y.a;							\
517 	case OP_EQ: return (T)max_t(t, x.a, y.a) <= (T)min_t(t, x.b, y.b);			\
518 	case OP_NE: return !((T)x.a == (T)x.b && (T)y.a == (T)y.b && (T)x.a == (T)y.a);		\
519 	default: printf("range_canbe op %d\n", op); exit(1);					\
520 	}											\
521 } while (0)
522 
523 	switch (t) {
524 	case U64: { range_canbe(u64); }
525 	case U32: { range_canbe(u32); }
526 	case S64: { range_canbe(s64); }
527 	case S32: { range_canbe(s32); }
528 	default: printf("range_canbe!\n"); exit(1);
529 	}
530 #undef range_canbe
531 }
532 
533 /* Does register with range [x.a, x.b] *ALWAYS* satisfy
534  * OP (<, <=, >, >=, ==, !=) relation to
535  * a register with range [y.a, y.b]
536  * _in *num_t* domain_
537  */
range_always_op(enum num_t t,struct range x,struct range y,enum op op)538 static bool range_always_op(enum num_t t, struct range x, struct range y, enum op op)
539 {
540 	/* always op <=> ! canbe complement(op) */
541 	return !range_canbe_op(t, x, y, complement_op(op));
542 }
543 
544 /* Does register with range [x.a, x.b] *NEVER* satisfy
545  * OP (<, <=, >, >=, ==, !=) relation to
546  * a register with range [y.a, y.b]
547  * _in *num_t* domain_
548  */
range_never_op(enum num_t t,struct range x,struct range y,enum op op)549 static bool range_never_op(enum num_t t, struct range x, struct range y, enum op op)
550 {
551 	return !range_canbe_op(t, x, y, op);
552 }
553 
554 /* similar to verifier's is_branch_taken():
555  *    1 - always taken;
556  *    0 - never taken,
557  *   -1 - unsure.
558  */
range_branch_taken_op(enum num_t t,struct range x,struct range y,enum op op)559 static int range_branch_taken_op(enum num_t t, struct range x, struct range y, enum op op)
560 {
561 	if (range_always_op(t, x, y, op))
562 		return 1;
563 	if (range_never_op(t, x, y, op))
564 		return 0;
565 	return -1;
566 }
567 
568 /* What would be the new estimates for register x and y ranges assuming truthful
569  * OP comparison between them. I.e., (x OP y == true) => x <- newx, y <- newy.
570  *
571  * We assume "interesting" cases where ranges overlap. Cases where it's
572  * obvious that (x OP y) is either always true or false should be filtered with
573  * range_never and range_always checks.
574  */
range_cond(enum num_t t,struct range x,struct range y,enum op op,struct range * newx,struct range * newy)575 static void range_cond(enum num_t t, struct range x, struct range y,
576 		       enum op op, struct range *newx, struct range *newy)
577 {
578 	if (!range_canbe_op(t, x, y, op)) {
579 		/* nothing to adjust, can't happen, return original values */
580 		*newx = x;
581 		*newy = y;
582 		return;
583 	}
584 	switch (op) {
585 	case OP_LT:
586 		*newx = range(t, x.a, min_t(t, x.b, y.b - 1));
587 		*newy = range(t, max_t(t, x.a + 1, y.a), y.b);
588 		break;
589 	case OP_LE:
590 		*newx = range(t, x.a, min_t(t, x.b, y.b));
591 		*newy = range(t, max_t(t, x.a, y.a), y.b);
592 		break;
593 	case OP_GT:
594 		*newx = range(t, max_t(t, x.a, y.a + 1), x.b);
595 		*newy = range(t, y.a, min_t(t, x.b - 1, y.b));
596 		break;
597 	case OP_GE:
598 		*newx = range(t, max_t(t, x.a, y.a), x.b);
599 		*newy = range(t, y.a, min_t(t, x.b, y.b));
600 		break;
601 	case OP_EQ:
602 		*newx = range(t, max_t(t, x.a, y.a), min_t(t, x.b, y.b));
603 		*newy = range(t, max_t(t, x.a, y.a), min_t(t, x.b, y.b));
604 		break;
605 	case OP_NE:
606 		/* below logic is supported by the verifier now */
607 		if (x.a == x.b && x.a == y.a) {
608 			/* X is a constant matching left side of Y */
609 			*newx = range(t, x.a, x.b);
610 			*newy = range(t, y.a + 1, y.b);
611 		} else if (x.a == x.b && x.b == y.b) {
612 			/* X is a constant matching rigth side of Y */
613 			*newx = range(t, x.a, x.b);
614 			*newy = range(t, y.a, y.b - 1);
615 		} else if (y.a == y.b && x.a == y.a) {
616 			/* Y is a constant matching left side of X */
617 			*newx = range(t, x.a + 1, x.b);
618 			*newy = range(t, y.a, y.b);
619 		} else if (y.a == y.b && x.b == y.b) {
620 			/* Y is a constant matching rigth side of X */
621 			*newx = range(t, x.a, x.b - 1);
622 			*newy = range(t, y.a, y.b);
623 		} else {
624 			/* generic case, can't derive more information */
625 			*newx = range(t, x.a, x.b);
626 			*newy = range(t, y.a, y.b);
627 		}
628 
629 		break;
630 	default:
631 		break;
632 	}
633 }
634 
635 /* =======================
636  * REGISTER STATE HANDLING
637  * =======================
638  */
639 struct reg_state {
640 	struct range r[4]; /* indexed by enum num_t: U64, U32, S64, S32 */
641 	bool valid;
642 };
643 
print_reg_state(struct reg_state * r,const char * sfx)644 static void print_reg_state(struct reg_state *r, const char *sfx)
645 {
646 	DEFINE_STRBUF(sb, 512);
647 	enum num_t t;
648 	int cnt = 0;
649 
650 	if (!r->valid) {
651 		printf("<not found>%s", sfx);
652 		return;
653 	}
654 
655 	snappendf(sb, "scalar(");
656 	for (t = first_t; t <= last_t; t++) {
657 		snappendf(sb, "%s%s=", cnt++ ? "," : "", t_str(t));
658 		snprintf_range(t, sb, r->r[t]);
659 	}
660 	snappendf(sb, ")");
661 
662 	printf("%s%s", sb->buf, sfx);
663 }
664 
print_refinement(enum num_t s_t,struct range src,enum num_t d_t,struct range old,struct range new,const char * ctx)665 static void print_refinement(enum num_t s_t, struct range src,
666 			     enum num_t d_t, struct range old, struct range new,
667 			     const char *ctx)
668 {
669 	printf("REFINING (%s) (%s)SRC=", ctx, t_str(s_t));
670 	print_range(s_t, src, "");
671 	printf(" (%s)DST_OLD=", t_str(d_t));
672 	print_range(d_t, old, "");
673 	printf(" (%s)DST_NEW=", t_str(d_t));
674 	print_range(d_t, new, "\n");
675 }
676 
reg_state_refine(struct reg_state * r,enum num_t t,struct range x,const char * ctx)677 static void reg_state_refine(struct reg_state *r, enum num_t t, struct range x, const char *ctx)
678 {
679 	enum num_t d_t, s_t;
680 	struct range old;
681 	bool keep_going = false;
682 
683 again:
684 	/* try to derive new knowledge from just learned range x of type t */
685 	for (d_t = first_t; d_t <= last_t; d_t++) {
686 		old = r->r[d_t];
687 		r->r[d_t] = range_refine(d_t, r->r[d_t], t, x);
688 		if (!range_eq(r->r[d_t], old)) {
689 			keep_going = true;
690 			if (env.verbosity >= VERBOSE_VERY)
691 				print_refinement(t, x, d_t, old, r->r[d_t], ctx);
692 		}
693 	}
694 
695 	/* now see if we can derive anything new from updated reg_state's ranges */
696 	for (s_t = first_t; s_t <= last_t; s_t++) {
697 		for (d_t = first_t; d_t <= last_t; d_t++) {
698 			old = r->r[d_t];
699 			r->r[d_t] = range_refine(d_t, r->r[d_t], s_t, r->r[s_t]);
700 			if (!range_eq(r->r[d_t], old)) {
701 				keep_going = true;
702 				if (env.verbosity >= VERBOSE_VERY)
703 					print_refinement(s_t, r->r[s_t], d_t, old, r->r[d_t], ctx);
704 			}
705 		}
706 	}
707 
708 	/* keep refining until we converge */
709 	if (keep_going) {
710 		keep_going = false;
711 		goto again;
712 	}
713 }
714 
reg_state_set_const(struct reg_state * rs,enum num_t t,u64 val)715 static void reg_state_set_const(struct reg_state *rs, enum num_t t, u64 val)
716 {
717 	enum num_t tt;
718 
719 	rs->valid = true;
720 	for (tt = first_t; tt <= last_t; tt++)
721 		rs->r[tt] = tt == t ? range(t, val, val) : unkn[tt];
722 
723 	reg_state_refine(rs, t, rs->r[t], "CONST");
724 }
725 
reg_state_cond(enum num_t t,struct reg_state * x,struct reg_state * y,enum op op,struct reg_state * newx,struct reg_state * newy,const char * ctx)726 static void reg_state_cond(enum num_t t, struct reg_state *x, struct reg_state *y, enum op op,
727 			   struct reg_state *newx, struct reg_state *newy, const char *ctx)
728 {
729 	char buf[32];
730 	enum num_t ts[2];
731 	struct reg_state xx = *x, yy = *y;
732 	int i, t_cnt;
733 	struct range z1, z2;
734 
735 	if (op == OP_EQ || op == OP_NE) {
736 		/* OP_EQ and OP_NE are sign-agnostic, so we need to process
737 		 * both signed and unsigned domains at the same time
738 		 */
739 		ts[0] = t_unsigned(t);
740 		ts[1] = t_signed(t);
741 		t_cnt = 2;
742 	} else {
743 		ts[0] = t;
744 		t_cnt = 1;
745 	}
746 
747 	for (i = 0; i < t_cnt; i++) {
748 		t = ts[i];
749 		z1 = x->r[t];
750 		z2 = y->r[t];
751 
752 		range_cond(t, z1, z2, op, &z1, &z2);
753 
754 		if (newx) {
755 			snprintf(buf, sizeof(buf), "%s R1", ctx);
756 			reg_state_refine(&xx, t, z1, buf);
757 		}
758 		if (newy) {
759 			snprintf(buf, sizeof(buf), "%s R2", ctx);
760 			reg_state_refine(&yy, t, z2, buf);
761 		}
762 	}
763 
764 	if (newx)
765 		*newx = xx;
766 	if (newy)
767 		*newy = yy;
768 }
769 
reg_state_branch_taken_op(enum num_t t,struct reg_state * x,struct reg_state * y,enum op op)770 static int reg_state_branch_taken_op(enum num_t t, struct reg_state *x, struct reg_state *y,
771 				     enum op op)
772 {
773 	if (op == OP_EQ || op == OP_NE) {
774 		/* OP_EQ and OP_NE are sign-agnostic */
775 		enum num_t tu = t_unsigned(t);
776 		enum num_t ts = t_signed(t);
777 		int br_u, br_s, br;
778 
779 		br_u = range_branch_taken_op(tu, x->r[tu], y->r[tu], op);
780 		br_s = range_branch_taken_op(ts, x->r[ts], y->r[ts], op);
781 
782 		if (br_u >= 0 && br_s >= 0 && br_u != br_s)
783 			ASSERT_FALSE(true, "branch taken inconsistency!\n");
784 
785 		/* if 64-bit ranges are indecisive, use 32-bit subranges to
786 		 * eliminate always/never taken branches, if possible
787 		 */
788 		if (br_u == -1 && (t == U64 || t == S64)) {
789 			br = range_branch_taken_op(U32, x->r[U32], y->r[U32], op);
790 			/* we can only reject for OP_EQ, never take branch
791 			 * based on lower 32 bits
792 			 */
793 			if (op == OP_EQ && br == 0)
794 				return 0;
795 			/* for OP_NEQ we can be conclusive only if lower 32 bits
796 			 * differ and thus inequality branch is always taken
797 			 */
798 			if (op == OP_NE && br == 1)
799 				return 1;
800 
801 			br = range_branch_taken_op(S32, x->r[S32], y->r[S32], op);
802 			if (op == OP_EQ && br == 0)
803 				return 0;
804 			if (op == OP_NE && br == 1)
805 				return 1;
806 		}
807 
808 		return br_u >= 0 ? br_u : br_s;
809 	}
810 	return range_branch_taken_op(t, x->r[t], y->r[t], op);
811 }
812 
813 /* =====================================
814  * BPF PROGS GENERATION AND VERIFICATION
815  * =====================================
816  */
817 struct case_spec {
818 	/* whether to init full register (r1) or sub-register (w1) */
819 	bool init_subregs;
820 	/* whether to establish initial value range on full register (r1) or
821 	 * sub-register (w1)
822 	 */
823 	bool setup_subregs;
824 	/* whether to establish initial value range using signed or unsigned
825 	 * comparisons (i.e., initialize umin/umax or smin/smax directly)
826 	 */
827 	bool setup_signed;
828 	/* whether to perform comparison on full registers or sub-registers */
829 	bool compare_subregs;
830 	/* whether to perform comparison using signed or unsigned operations */
831 	bool compare_signed;
832 };
833 
834 /* Generate test BPF program based on provided test ranges, operation, and
835  * specifications about register bitness and signedness.
836  */
load_range_cmp_prog(struct range x,struct range y,enum op op,int branch_taken,struct case_spec spec,char * log_buf,size_t log_sz,int * false_pos,int * true_pos)837 static int load_range_cmp_prog(struct range x, struct range y, enum op op,
838 			       int branch_taken, struct case_spec spec,
839 			       char *log_buf, size_t log_sz,
840 			       int *false_pos, int *true_pos)
841 {
842 #define emit(insn) ({							\
843 	struct bpf_insn __insns[] = { insn };				\
844 	int __i;							\
845 	for (__i = 0; __i < ARRAY_SIZE(__insns); __i++)			\
846 		insns[cur_pos + __i] = __insns[__i];			\
847 	cur_pos += __i;							\
848 })
849 #define JMP_TO(target) (target - cur_pos - 1)
850 	int cur_pos = 0, exit_pos, fd, op_code;
851 	struct bpf_insn insns[64];
852 	LIBBPF_OPTS(bpf_prog_load_opts, opts,
853 		.log_level = 2,
854 		.log_buf = log_buf,
855 		.log_size = log_sz,
856 		.prog_flags = testing_prog_flags(),
857 	);
858 
859 	/* ; skip exit block below
860 	 * goto +2;
861 	 */
862 	emit(BPF_JMP_A(2));
863 	exit_pos = cur_pos;
864 	/* ; exit block for all the preparatory conditionals
865 	 * out:
866 	 * r0 = 0;
867 	 * exit;
868 	 */
869 	emit(BPF_MOV64_IMM(BPF_REG_0, 0));
870 	emit(BPF_EXIT_INSN());
871 	/*
872 	 * ; assign r6/w6 and r7/w7 unpredictable u64/u32 value
873 	 * call bpf_get_current_pid_tgid;
874 	 * r6 = r0;               | w6 = w0;
875 	 * call bpf_get_current_pid_tgid;
876 	 * r7 = r0;               | w7 = w0;
877 	 */
878 	emit(BPF_EMIT_CALL(BPF_FUNC_get_current_pid_tgid));
879 	if (spec.init_subregs)
880 		emit(BPF_MOV32_REG(BPF_REG_6, BPF_REG_0));
881 	else
882 		emit(BPF_MOV64_REG(BPF_REG_6, BPF_REG_0));
883 	emit(BPF_EMIT_CALL(BPF_FUNC_get_current_pid_tgid));
884 	if (spec.init_subregs)
885 		emit(BPF_MOV32_REG(BPF_REG_7, BPF_REG_0));
886 	else
887 		emit(BPF_MOV64_REG(BPF_REG_7, BPF_REG_0));
888 	/* ; setup initial r6/w6 possible value range ([x.a, x.b])
889 	 * r1 = %[x.a] ll;        | w1 = %[x.a];
890 	 * r2 = %[x.b] ll;        | w2 = %[x.b];
891 	 * if r6 < r1 goto out;   | if w6 < w1 goto out;
892 	 * if r6 > r2 goto out;   | if w6 > w2 goto out;
893 	 */
894 	if (spec.setup_subregs) {
895 		emit(BPF_MOV32_IMM(BPF_REG_1, (s32)x.a));
896 		emit(BPF_MOV32_IMM(BPF_REG_2, (s32)x.b));
897 		emit(BPF_JMP32_REG(spec.setup_signed ? BPF_JSLT : BPF_JLT,
898 				   BPF_REG_6, BPF_REG_1, JMP_TO(exit_pos)));
899 		emit(BPF_JMP32_REG(spec.setup_signed ? BPF_JSGT : BPF_JGT,
900 				   BPF_REG_6, BPF_REG_2, JMP_TO(exit_pos)));
901 	} else {
902 		emit(BPF_LD_IMM64(BPF_REG_1, x.a));
903 		emit(BPF_LD_IMM64(BPF_REG_2, x.b));
904 		emit(BPF_JMP_REG(spec.setup_signed ? BPF_JSLT : BPF_JLT,
905 				 BPF_REG_6, BPF_REG_1, JMP_TO(exit_pos)));
906 		emit(BPF_JMP_REG(spec.setup_signed ? BPF_JSGT : BPF_JGT,
907 				 BPF_REG_6, BPF_REG_2, JMP_TO(exit_pos)));
908 	}
909 	/* ; setup initial r7/w7 possible value range ([y.a, y.b])
910 	 * r1 = %[y.a] ll;        | w1 = %[y.a];
911 	 * r2 = %[y.b] ll;        | w2 = %[y.b];
912 	 * if r7 < r1 goto out;   | if w7 < w1 goto out;
913 	 * if r7 > r2 goto out;   | if w7 > w2 goto out;
914 	 */
915 	if (spec.setup_subregs) {
916 		emit(BPF_MOV32_IMM(BPF_REG_1, (s32)y.a));
917 		emit(BPF_MOV32_IMM(BPF_REG_2, (s32)y.b));
918 		emit(BPF_JMP32_REG(spec.setup_signed ? BPF_JSLT : BPF_JLT,
919 				   BPF_REG_7, BPF_REG_1, JMP_TO(exit_pos)));
920 		emit(BPF_JMP32_REG(spec.setup_signed ? BPF_JSGT : BPF_JGT,
921 				   BPF_REG_7, BPF_REG_2, JMP_TO(exit_pos)));
922 	} else {
923 		emit(BPF_LD_IMM64(BPF_REG_1, y.a));
924 		emit(BPF_LD_IMM64(BPF_REG_2, y.b));
925 		emit(BPF_JMP_REG(spec.setup_signed ? BPF_JSLT : BPF_JLT,
926 				 BPF_REG_7, BPF_REG_1, JMP_TO(exit_pos)));
927 		emit(BPF_JMP_REG(spec.setup_signed ? BPF_JSGT : BPF_JGT,
928 				 BPF_REG_7, BPF_REG_2, JMP_TO(exit_pos)));
929 	}
930 	/* ; range test instruction
931 	 * if r6 <op> r7 goto +3; | if w6 <op> w7 goto +3;
932 	 */
933 	switch (op) {
934 	case OP_LT: op_code = spec.compare_signed ? BPF_JSLT : BPF_JLT; break;
935 	case OP_LE: op_code = spec.compare_signed ? BPF_JSLE : BPF_JLE; break;
936 	case OP_GT: op_code = spec.compare_signed ? BPF_JSGT : BPF_JGT; break;
937 	case OP_GE: op_code = spec.compare_signed ? BPF_JSGE : BPF_JGE; break;
938 	case OP_EQ: op_code = BPF_JEQ; break;
939 	case OP_NE: op_code = BPF_JNE; break;
940 	default:
941 		printf("unrecognized op %d\n", op);
942 		return -ENOTSUP;
943 	}
944 	/* ; BEFORE conditional, r0/w0 = {r6/w6,r7/w7} is to extract verifier state reliably
945 	 * ; this is used for debugging, as verifier doesn't always print
946 	 * ; registers states as of condition jump instruction (e.g., when
947 	 * ; precision marking happens)
948 	 * r0 = r6;               | w0 = w6;
949 	 * r0 = r7;               | w0 = w7;
950 	 */
951 	if (spec.compare_subregs) {
952 		emit(BPF_MOV32_REG(BPF_REG_0, BPF_REG_6));
953 		emit(BPF_MOV32_REG(BPF_REG_0, BPF_REG_7));
954 	} else {
955 		emit(BPF_MOV64_REG(BPF_REG_0, BPF_REG_6));
956 		emit(BPF_MOV64_REG(BPF_REG_0, BPF_REG_7));
957 	}
958 	if (spec.compare_subregs)
959 		emit(BPF_JMP32_REG(op_code, BPF_REG_6, BPF_REG_7, 3));
960 	else
961 		emit(BPF_JMP_REG(op_code, BPF_REG_6, BPF_REG_7, 3));
962 	/* ; FALSE branch, r0/w0 = {r6/w6,r7/w7} is to extract verifier state reliably
963 	 * r0 = r6;               | w0 = w6;
964 	 * r0 = r7;               | w0 = w7;
965 	 * exit;
966 	 */
967 	*false_pos = cur_pos;
968 	if (spec.compare_subregs) {
969 		emit(BPF_MOV32_REG(BPF_REG_0, BPF_REG_6));
970 		emit(BPF_MOV32_REG(BPF_REG_0, BPF_REG_7));
971 	} else {
972 		emit(BPF_MOV64_REG(BPF_REG_0, BPF_REG_6));
973 		emit(BPF_MOV64_REG(BPF_REG_0, BPF_REG_7));
974 	}
975 	if (branch_taken == 1) /* false branch is never taken */
976 		emit(BPF_EMIT_CALL(0xDEAD)); /* poison this branch */
977 	else
978 		emit(BPF_EXIT_INSN());
979 	/* ; TRUE branch, r0/w0 = {r6/w6,r7/w7} is to extract verifier state reliably
980 	 * r0 = r6;               | w0 = w6;
981 	 * r0 = r7;               | w0 = w7;
982 	 * exit;
983 	 */
984 	*true_pos = cur_pos;
985 	if (spec.compare_subregs) {
986 		emit(BPF_MOV32_REG(BPF_REG_0, BPF_REG_6));
987 		emit(BPF_MOV32_REG(BPF_REG_0, BPF_REG_7));
988 	} else {
989 		emit(BPF_MOV64_REG(BPF_REG_0, BPF_REG_6));
990 		emit(BPF_MOV64_REG(BPF_REG_0, BPF_REG_7));
991 	}
992 	if (branch_taken == 0) /* true branch is never taken */
993 		emit(BPF_EMIT_CALL(0xDEAD)); /* poison this branch */
994 	emit(BPF_EXIT_INSN()); /* last instruction has to be exit */
995 
996 	fd = bpf_prog_load(BPF_PROG_TYPE_RAW_TRACEPOINT, "reg_bounds_test",
997 			   "GPL", insns, cur_pos, &opts);
998 	if (fd < 0)
999 		return fd;
1000 
1001 	close(fd);
1002 	return 0;
1003 #undef emit
1004 #undef JMP_TO
1005 }
1006 
1007 #define str_has_pfx(str, pfx) (strncmp(str, pfx, strlen(pfx)) == 0)
1008 
1009 /* Parse register state from verifier log.
1010  * `s` should point to the start of "Rx = ..." substring in the verifier log.
1011  */
parse_reg_state(const char * s,struct reg_state * reg)1012 static int parse_reg_state(const char *s, struct reg_state *reg)
1013 {
1014 	/* There are two generic forms for SCALAR register:
1015 	 * - known constant: R6_rwD=P%lld
1016 	 * - range: R6_rwD=scalar(id=1,...), where "..." is a comma-separated
1017 	 *   list of optional range specifiers:
1018 	 *     - umin=%llu, if missing, assumed 0;
1019 	 *     - umax=%llu, if missing, assumed U64_MAX;
1020 	 *     - smin=%lld, if missing, assumed S64_MIN;
1021 	 *     - smax=%lld, if missing, assumed S64_MAX;
1022 	 *     - umin32=%d, if missing, assumed 0;
1023 	 *     - umax32=%d, if missing, assumed U32_MAX;
1024 	 *     - smin32=%d, if missing, assumed S32_MIN;
1025 	 *     - smax32=%d, if missing, assumed S32_MAX;
1026 	 *     - var_off=(%#llx; %#llx), tnum part, we don't care about it.
1027 	 *
1028 	 * If some of the values are equal, they will be grouped (but min/max
1029 	 * are not mixed together, and similarly negative values are not
1030 	 * grouped with non-negative ones). E.g.:
1031 	 *
1032 	 *   R6_w=Pscalar(smin=smin32=0, smax=umax=umax32=1000)
1033 	 *
1034 	 * _rwD part is optional (and any of the letters can be missing).
1035 	 * P (precision mark) is optional as well.
1036 	 *
1037 	 * Anything inside scalar() is optional, including id, of course.
1038 	 */
1039 	struct {
1040 		const char *pfx;
1041 		u64 *dst, def;
1042 		bool is_32, is_set;
1043 	} *f, fields[8] = {
1044 		{"smin=", &reg->r[S64].a, S64_MIN},
1045 		{"smax=", &reg->r[S64].b, S64_MAX},
1046 		{"umin=", &reg->r[U64].a, 0},
1047 		{"umax=", &reg->r[U64].b, U64_MAX},
1048 		{"smin32=", &reg->r[S32].a, (u32)S32_MIN, true},
1049 		{"smax32=", &reg->r[S32].b, (u32)S32_MAX, true},
1050 		{"umin32=", &reg->r[U32].a, 0,            true},
1051 		{"umax32=", &reg->r[U32].b, U32_MAX,      true},
1052 	};
1053 	const char *p;
1054 	int i;
1055 
1056 	p = strchr(s, '=');
1057 	if (!p)
1058 		return -EINVAL;
1059 	p++;
1060 	if (*p == 'P')
1061 		p++;
1062 
1063 	if (!str_has_pfx(p, "scalar(")) {
1064 		long long sval;
1065 		enum num_t t;
1066 
1067 		if (p[0] == '0' && p[1] == 'x') {
1068 			if (sscanf(p, "%llx", &sval) != 1)
1069 				return -EINVAL;
1070 		} else {
1071 			if (sscanf(p, "%lld", &sval) != 1)
1072 				return -EINVAL;
1073 		}
1074 
1075 		reg->valid = true;
1076 		for (t = first_t; t <= last_t; t++) {
1077 			reg->r[t] = range(t, sval, sval);
1078 		}
1079 		return 0;
1080 	}
1081 
1082 	p += sizeof("scalar");
1083 	while (p) {
1084 		int midxs[ARRAY_SIZE(fields)], mcnt = 0;
1085 		u64 val;
1086 
1087 		for (i = 0; i < ARRAY_SIZE(fields); i++) {
1088 			f = &fields[i];
1089 			if (!str_has_pfx(p, f->pfx))
1090 				continue;
1091 			midxs[mcnt++] = i;
1092 			p += strlen(f->pfx);
1093 		}
1094 
1095 		if (mcnt) {
1096 			/* populate all matched fields */
1097 			if (p[0] == '0' && p[1] == 'x') {
1098 				if (sscanf(p, "%llx", &val) != 1)
1099 					return -EINVAL;
1100 			} else {
1101 				if (sscanf(p, "%lld", &val) != 1)
1102 					return -EINVAL;
1103 			}
1104 
1105 			for (i = 0; i < mcnt; i++) {
1106 				f = &fields[midxs[i]];
1107 				f->is_set = true;
1108 				*f->dst = f->is_32 ? (u64)(u32)val : val;
1109 			}
1110 		} else if (str_has_pfx(p, "var_off")) {
1111 			/* skip "var_off=(0x0; 0x3f)" part completely */
1112 			p = strchr(p, ')');
1113 			if (!p)
1114 				return -EINVAL;
1115 			p++;
1116 		}
1117 
1118 		p = strpbrk(p, ",)");
1119 		if (*p == ')')
1120 			break;
1121 		if (p)
1122 			p++;
1123 	}
1124 
1125 	reg->valid = true;
1126 
1127 	for (i = 0; i < ARRAY_SIZE(fields); i++) {
1128 		f = &fields[i];
1129 		if (!f->is_set)
1130 			*f->dst = f->def;
1131 	}
1132 
1133 	return 0;
1134 }
1135 
1136 
1137 /* Parse all register states (TRUE/FALSE branches and DST/SRC registers)
1138  * out of the verifier log for a corresponding test case BPF program.
1139  */
parse_range_cmp_log(const char * log_buf,struct case_spec spec,int false_pos,int true_pos,struct reg_state * false1_reg,struct reg_state * false2_reg,struct reg_state * true1_reg,struct reg_state * true2_reg)1140 static int parse_range_cmp_log(const char *log_buf, struct case_spec spec,
1141 			       int false_pos, int true_pos,
1142 			       struct reg_state *false1_reg, struct reg_state *false2_reg,
1143 			       struct reg_state *true1_reg, struct reg_state *true2_reg)
1144 {
1145 	struct {
1146 		int insn_idx;
1147 		int reg_idx;
1148 		const char *reg_upper;
1149 		struct reg_state *state;
1150 	} specs[] = {
1151 		{false_pos,     6, "R6=", false1_reg},
1152 		{false_pos + 1, 7, "R7=", false2_reg},
1153 		{true_pos,      6, "R6=", true1_reg},
1154 		{true_pos + 1,  7, "R7=", true2_reg},
1155 	};
1156 	char buf[32];
1157 	const char *p = log_buf, *q;
1158 	int i, err;
1159 
1160 	for (i = 0; i < 4; i++) {
1161 		sprintf(buf, "%d: (%s) %s = %s%d", specs[i].insn_idx,
1162 			spec.compare_subregs ? "bc" : "bf",
1163 			spec.compare_subregs ? "w0" : "r0",
1164 			spec.compare_subregs ? "w" : "r", specs[i].reg_idx);
1165 
1166 		q = strstr(p, buf);
1167 		if (!q) {
1168 			*specs[i].state = (struct reg_state){.valid = false};
1169 			continue;
1170 		}
1171 		p = strstr(q, specs[i].reg_upper);
1172 		if (!p)
1173 			return -EINVAL;
1174 		err = parse_reg_state(p, specs[i].state);
1175 		if (err)
1176 			return -EINVAL;
1177 	}
1178 	return 0;
1179 }
1180 
1181 /* Validate ranges match, and print details if they don't */
assert_range_eq(enum num_t t,struct range x,struct range y,const char * ctx1,const char * ctx2)1182 static bool assert_range_eq(enum num_t t, struct range x, struct range y,
1183 			    const char *ctx1, const char *ctx2)
1184 {
1185 	DEFINE_STRBUF(sb, 512);
1186 
1187 	if (range_eq(x, y))
1188 		return true;
1189 
1190 	snappendf(sb, "MISMATCH %s.%s: ", ctx1, ctx2);
1191 	snprintf_range(t, sb, x);
1192 	snappendf(sb, " != ");
1193 	snprintf_range(t, sb, y);
1194 
1195 	printf("%s\n", sb->buf);
1196 
1197 	return false;
1198 }
1199 
1200 /* Validate that register states match, and print details if they don't */
assert_reg_state_eq(struct reg_state * r,struct reg_state * e,const char * ctx)1201 static bool assert_reg_state_eq(struct reg_state *r, struct reg_state *e, const char *ctx)
1202 {
1203 	bool ok = true;
1204 	enum num_t t;
1205 
1206 	if (r->valid != e->valid) {
1207 		printf("MISMATCH %s: actual %s != expected %s\n", ctx,
1208 		       r->valid ? "<valid>" : "<invalid>",
1209 		       e->valid ? "<valid>" : "<invalid>");
1210 		return false;
1211 	}
1212 
1213 	if (!r->valid)
1214 		return true;
1215 
1216 	for (t = first_t; t <= last_t; t++) {
1217 		if (!assert_range_eq(t, r->r[t], e->r[t], ctx, t_str(t)))
1218 			ok = false;
1219 	}
1220 
1221 	return ok;
1222 }
1223 
1224 /* Printf verifier log, filtering out irrelevant noise */
print_verifier_log(const char * buf)1225 static void print_verifier_log(const char *buf)
1226 {
1227 	const char *p;
1228 
1229 	while (buf[0]) {
1230 		p = strchrnul(buf, '\n');
1231 
1232 		/* filter out irrelevant precision backtracking logs */
1233 		if (str_has_pfx(buf, "mark_precise: "))
1234 			goto skip_line;
1235 
1236 		printf("%.*s\n", (int)(p - buf), buf);
1237 
1238 skip_line:
1239 		buf = *p == '\0' ? p : p + 1;
1240 	}
1241 }
1242 
1243 /* Simulate provided test case purely with our own range-based logic.
1244  * This is done to set up expectations for verifier's branch_taken logic and
1245  * verifier's register states in the verifier log.
1246  */
sim_case(enum num_t init_t,enum num_t cond_t,struct range x,struct range y,enum op op,struct reg_state * fr1,struct reg_state * fr2,struct reg_state * tr1,struct reg_state * tr2,int * branch_taken)1247 static void sim_case(enum num_t init_t, enum num_t cond_t,
1248 		     struct range x, struct range y, enum op op,
1249 		     struct reg_state *fr1, struct reg_state *fr2,
1250 		     struct reg_state *tr1, struct reg_state *tr2,
1251 		     int *branch_taken)
1252 {
1253 	const u64 A = x.a;
1254 	const u64 B = x.b;
1255 	const u64 C = y.a;
1256 	const u64 D = y.b;
1257 	struct reg_state rc;
1258 	enum op rev_op = complement_op(op);
1259 	enum num_t t;
1260 
1261 	fr1->valid = fr2->valid = true;
1262 	tr1->valid = tr2->valid = true;
1263 	for (t = first_t; t <= last_t; t++) {
1264 		/* if we are initializing using 32-bit subregisters,
1265 		 * full registers get upper 32 bits zeroed automatically
1266 		 */
1267 		struct range z = t_is_32(init_t) ? unkn_subreg(t) : unkn[t];
1268 
1269 		fr1->r[t] = fr2->r[t] = tr1->r[t] = tr2->r[t] = z;
1270 	}
1271 
1272 	/* step 1: r1 >= A, r2 >= C */
1273 	reg_state_set_const(&rc, init_t, A);
1274 	reg_state_cond(init_t, fr1, &rc, OP_GE, fr1, NULL, "r1>=A");
1275 	reg_state_set_const(&rc, init_t, C);
1276 	reg_state_cond(init_t, fr2, &rc, OP_GE, fr2, NULL, "r2>=C");
1277 	*tr1 = *fr1;
1278 	*tr2 = *fr2;
1279 	if (env.verbosity >= VERBOSE_VERY) {
1280 		printf("STEP1 (%s) R1: ", t_str(init_t)); print_reg_state(fr1, "\n");
1281 		printf("STEP1 (%s) R2: ", t_str(init_t)); print_reg_state(fr2, "\n");
1282 	}
1283 
1284 	/* step 2: r1 <= B, r2 <= D */
1285 	reg_state_set_const(&rc, init_t, B);
1286 	reg_state_cond(init_t, fr1, &rc, OP_LE, fr1, NULL, "r1<=B");
1287 	reg_state_set_const(&rc, init_t, D);
1288 	reg_state_cond(init_t, fr2, &rc, OP_LE, fr2, NULL, "r2<=D");
1289 	*tr1 = *fr1;
1290 	*tr2 = *fr2;
1291 	if (env.verbosity >= VERBOSE_VERY) {
1292 		printf("STEP2 (%s) R1: ", t_str(init_t)); print_reg_state(fr1, "\n");
1293 		printf("STEP2 (%s) R2: ", t_str(init_t)); print_reg_state(fr2, "\n");
1294 	}
1295 
1296 	/* step 3: r1 <op> r2 */
1297 	*branch_taken = reg_state_branch_taken_op(cond_t, fr1, fr2, op);
1298 	fr1->valid = fr2->valid = false;
1299 	tr1->valid = tr2->valid = false;
1300 	if (*branch_taken != 1) { /* FALSE is possible */
1301 		fr1->valid = fr2->valid = true;
1302 		reg_state_cond(cond_t, fr1, fr2, rev_op, fr1, fr2, "FALSE");
1303 	}
1304 	if (*branch_taken != 0) { /* TRUE is possible */
1305 		tr1->valid = tr2->valid = true;
1306 		reg_state_cond(cond_t, tr1, tr2, op, tr1, tr2, "TRUE");
1307 	}
1308 	if (env.verbosity >= VERBOSE_VERY) {
1309 		printf("STEP3 (%s) FALSE R1:", t_str(cond_t)); print_reg_state(fr1, "\n");
1310 		printf("STEP3 (%s) FALSE R2:", t_str(cond_t)); print_reg_state(fr2, "\n");
1311 		printf("STEP3 (%s) TRUE  R1:", t_str(cond_t)); print_reg_state(tr1, "\n");
1312 		printf("STEP3 (%s) TRUE  R2:", t_str(cond_t)); print_reg_state(tr2, "\n");
1313 	}
1314 }
1315 
1316 /* ===============================
1317  * HIGH-LEVEL TEST CASE VALIDATION
1318  * ===============================
1319  */
1320 static u32 upper_seeds[] = {
1321 	0,
1322 	1,
1323 	U32_MAX,
1324 	U32_MAX - 1,
1325 	S32_MAX,
1326 	(u32)S32_MIN,
1327 };
1328 
1329 static u32 lower_seeds[] = {
1330 	0,
1331 	1,
1332 	2, (u32)-2,
1333 	255, (u32)-255,
1334 	UINT_MAX,
1335 	UINT_MAX - 1,
1336 	INT_MAX,
1337 	(u32)INT_MIN,
1338 };
1339 
1340 struct ctx {
1341 	int val_cnt, subval_cnt, range_cnt, subrange_cnt;
1342 	u64 uvals[ARRAY_SIZE(upper_seeds) * ARRAY_SIZE(lower_seeds)];
1343 	s64 svals[ARRAY_SIZE(upper_seeds) * ARRAY_SIZE(lower_seeds)];
1344 	u32 usubvals[ARRAY_SIZE(lower_seeds)];
1345 	s32 ssubvals[ARRAY_SIZE(lower_seeds)];
1346 	struct range *uranges, *sranges;
1347 	struct range *usubranges, *ssubranges;
1348 	int max_failure_cnt, cur_failure_cnt;
1349 	int total_case_cnt, case_cnt;
1350 	int rand_case_cnt;
1351 	unsigned rand_seed;
1352 	__u64 start_ns;
1353 	char progress_ctx[64];
1354 };
1355 
cleanup_ctx(struct ctx * ctx)1356 static void cleanup_ctx(struct ctx *ctx)
1357 {
1358 	free(ctx->uranges);
1359 	free(ctx->sranges);
1360 	free(ctx->usubranges);
1361 	free(ctx->ssubranges);
1362 }
1363 
1364 struct subtest_case {
1365 	enum num_t init_t;
1366 	enum num_t cond_t;
1367 	struct range x;
1368 	struct range y;
1369 	enum op op;
1370 };
1371 
subtest_case_str(struct strbuf * sb,struct subtest_case * t,bool use_op)1372 static void subtest_case_str(struct strbuf *sb, struct subtest_case *t, bool use_op)
1373 {
1374 	snappendf(sb, "(%s)", t_str(t->init_t));
1375 	snprintf_range(t->init_t, sb, t->x);
1376 	snappendf(sb, " (%s)%s ", t_str(t->cond_t), use_op ? op_str(t->op) : "<op>");
1377 	snprintf_range(t->init_t, sb, t->y);
1378 }
1379 
1380 /* Generate and validate test case based on specific combination of setup
1381  * register ranges (including their expected num_t domain), and conditional
1382  * operation to perform (including num_t domain in which it has to be
1383  * performed)
1384  */
verify_case_op(enum num_t init_t,enum num_t cond_t,struct range x,struct range y,enum op op)1385 static int verify_case_op(enum num_t init_t, enum num_t cond_t,
1386 			  struct range x, struct range y, enum op op)
1387 {
1388 	char log_buf[256 * 1024];
1389 	size_t log_sz = sizeof(log_buf);
1390 	int err, false_pos = 0, true_pos = 0, branch_taken;
1391 	struct reg_state fr1, fr2, tr1, tr2;
1392 	struct reg_state fe1, fe2, te1, te2;
1393 	bool failed = false;
1394 	struct case_spec spec = {
1395 		.init_subregs = (init_t == U32 || init_t == S32),
1396 		.setup_subregs = (init_t == U32 || init_t == S32),
1397 		.setup_signed = (init_t == S64 || init_t == S32),
1398 		.compare_subregs = (cond_t == U32 || cond_t == S32),
1399 		.compare_signed = (cond_t == S64 || cond_t == S32),
1400 	};
1401 
1402 	log_buf[0] = '\0';
1403 
1404 	sim_case(init_t, cond_t, x, y, op, &fe1, &fe2, &te1, &te2, &branch_taken);
1405 
1406 	err = load_range_cmp_prog(x, y, op, branch_taken, spec,
1407 				  log_buf, log_sz, &false_pos, &true_pos);
1408 	if (err) {
1409 		ASSERT_OK(err, "load_range_cmp_prog");
1410 		failed = true;
1411 	}
1412 
1413 	err = parse_range_cmp_log(log_buf, spec, false_pos, true_pos,
1414 				  &fr1, &fr2, &tr1, &tr2);
1415 	if (err) {
1416 		ASSERT_OK(err, "parse_range_cmp_log");
1417 		failed = true;
1418 	}
1419 
1420 	if (!assert_reg_state_eq(&fr1, &fe1, "false_reg1") ||
1421 	    !assert_reg_state_eq(&fr2, &fe2, "false_reg2") ||
1422 	    !assert_reg_state_eq(&tr1, &te1, "true_reg1") ||
1423 	    !assert_reg_state_eq(&tr2, &te2, "true_reg2")) {
1424 		failed = true;
1425 	}
1426 
1427 	if (failed || env.verbosity >= VERBOSE_NORMAL) {
1428 		if (failed || env.verbosity >= VERBOSE_VERY) {
1429 			printf("VERIFIER LOG:\n========================\n");
1430 			print_verifier_log(log_buf);
1431 			printf("=====================\n");
1432 		}
1433 		printf("ACTUAL   FALSE1: "); print_reg_state(&fr1, "\n");
1434 		printf("EXPECTED FALSE1: "); print_reg_state(&fe1, "\n");
1435 		printf("ACTUAL   FALSE2: "); print_reg_state(&fr2, "\n");
1436 		printf("EXPECTED FALSE2: "); print_reg_state(&fe2, "\n");
1437 		printf("ACTUAL   TRUE1:  "); print_reg_state(&tr1, "\n");
1438 		printf("EXPECTED TRUE1:  "); print_reg_state(&te1, "\n");
1439 		printf("ACTUAL   TRUE2:  "); print_reg_state(&tr2, "\n");
1440 		printf("EXPECTED TRUE2:  "); print_reg_state(&te2, "\n");
1441 
1442 		return failed ? -EINVAL : 0;
1443 	}
1444 
1445 	return 0;
1446 }
1447 
1448 /* Given setup ranges and number types, go over all supported operations,
1449  * generating individual subtest for each allowed combination
1450  */
verify_case_opt(struct ctx * ctx,enum num_t init_t,enum num_t cond_t,struct range x,struct range y,bool is_subtest)1451 static int verify_case_opt(struct ctx *ctx, enum num_t init_t, enum num_t cond_t,
1452 			   struct range x, struct range y, bool is_subtest)
1453 {
1454 	DEFINE_STRBUF(sb, 256);
1455 	int err;
1456 	struct subtest_case sub = {
1457 		.init_t = init_t,
1458 		.cond_t = cond_t,
1459 		.x = x,
1460 		.y = y,
1461 	};
1462 
1463 	sb->pos = 0; /* reset position in strbuf */
1464 	subtest_case_str(sb, &sub, false /* ignore op */);
1465 	if (is_subtest && !test__start_subtest(sb->buf))
1466 		return 0;
1467 
1468 	for (sub.op = first_op; sub.op <= last_op; sub.op++) {
1469 		sb->pos = 0; /* reset position in strbuf */
1470 		subtest_case_str(sb, &sub, true /* print op */);
1471 
1472 		if (env.verbosity >= VERBOSE_NORMAL) /* this speeds up debugging */
1473 			printf("TEST CASE: %s\n", sb->buf);
1474 
1475 		err = verify_case_op(init_t, cond_t, x, y, sub.op);
1476 		if (err || env.verbosity >= VERBOSE_NORMAL)
1477 			ASSERT_OK(err, sb->buf);
1478 		if (err) {
1479 			ctx->cur_failure_cnt++;
1480 			if (ctx->cur_failure_cnt > ctx->max_failure_cnt)
1481 				return err;
1482 			return 0; /* keep testing other cases */
1483 		}
1484 		ctx->case_cnt++;
1485 		if ((ctx->case_cnt % 10000) == 0) {
1486 			double progress = (ctx->case_cnt + 0.0) / ctx->total_case_cnt;
1487 			u64 elapsed_ns = get_time_ns() - ctx->start_ns;
1488 			double remain_ns = elapsed_ns / progress * (1 - progress);
1489 
1490 			fprintf(env.stderr_saved, "PROGRESS (%s): %d/%d (%.2lf%%), "
1491 					    "elapsed %llu mins (%.2lf hrs), "
1492 					    "ETA %.0lf mins (%.2lf hrs)\n",
1493 				ctx->progress_ctx,
1494 				ctx->case_cnt, ctx->total_case_cnt, 100.0 * progress,
1495 				elapsed_ns / 1000000000 / 60,
1496 				elapsed_ns / 1000000000.0 / 3600,
1497 				remain_ns / 1000000000.0 / 60,
1498 				remain_ns / 1000000000.0 / 3600);
1499 		}
1500 	}
1501 
1502 	return 0;
1503 }
1504 
verify_case(struct ctx * ctx,enum num_t init_t,enum num_t cond_t,struct range x,struct range y)1505 static int verify_case(struct ctx *ctx, enum num_t init_t, enum num_t cond_t,
1506 		       struct range x, struct range y)
1507 {
1508 	return verify_case_opt(ctx, init_t, cond_t, x, y, true /* is_subtest */);
1509 }
1510 
1511 /* ================================
1512  * GENERATED CASES FROM SEED VALUES
1513  * ================================
1514  */
u64_cmp(const void * p1,const void * p2)1515 static int u64_cmp(const void *p1, const void *p2)
1516 {
1517 	u64 x1 = *(const u64 *)p1, x2 = *(const u64 *)p2;
1518 
1519 	return x1 != x2 ? (x1 < x2 ? -1 : 1) : 0;
1520 }
1521 
u32_cmp(const void * p1,const void * p2)1522 static int u32_cmp(const void *p1, const void *p2)
1523 {
1524 	u32 x1 = *(const u32 *)p1, x2 = *(const u32 *)p2;
1525 
1526 	return x1 != x2 ? (x1 < x2 ? -1 : 1) : 0;
1527 }
1528 
s64_cmp(const void * p1,const void * p2)1529 static int s64_cmp(const void *p1, const void *p2)
1530 {
1531 	s64 x1 = *(const s64 *)p1, x2 = *(const s64 *)p2;
1532 
1533 	return x1 != x2 ? (x1 < x2 ? -1 : 1) : 0;
1534 }
1535 
s32_cmp(const void * p1,const void * p2)1536 static int s32_cmp(const void *p1, const void *p2)
1537 {
1538 	s32 x1 = *(const s32 *)p1, x2 = *(const s32 *)p2;
1539 
1540 	return x1 != x2 ? (x1 < x2 ? -1 : 1) : 0;
1541 }
1542 
1543 /* Generate valid unique constants from seeds, both signed and unsigned */
gen_vals(struct ctx * ctx)1544 static void gen_vals(struct ctx *ctx)
1545 {
1546 	int i, j, cnt = 0;
1547 
1548 	for (i = 0; i < ARRAY_SIZE(upper_seeds); i++) {
1549 		for (j = 0; j < ARRAY_SIZE(lower_seeds); j++) {
1550 			ctx->uvals[cnt++] = (((u64)upper_seeds[i]) << 32) | lower_seeds[j];
1551 		}
1552 	}
1553 
1554 	/* sort and compact uvals (i.e., it's `sort | uniq`) */
1555 	qsort(ctx->uvals, cnt, sizeof(*ctx->uvals), u64_cmp);
1556 	for (i = 1, j = 0; i < cnt; i++) {
1557 		if (ctx->uvals[j] == ctx->uvals[i])
1558 			continue;
1559 		j++;
1560 		ctx->uvals[j] = ctx->uvals[i];
1561 	}
1562 	ctx->val_cnt = j + 1;
1563 
1564 	/* we have exactly the same number of s64 values, they are just in
1565 	 * a different order than u64s, so just sort them differently
1566 	 */
1567 	for (i = 0; i < ctx->val_cnt; i++)
1568 		ctx->svals[i] = ctx->uvals[i];
1569 	qsort(ctx->svals, ctx->val_cnt, sizeof(*ctx->svals), s64_cmp);
1570 
1571 	if (env.verbosity >= VERBOSE_SUPER) {
1572 		DEFINE_STRBUF(sb1, 256);
1573 		DEFINE_STRBUF(sb2, 256);
1574 
1575 		for (i = 0; i < ctx->val_cnt; i++) {
1576 			sb1->pos = sb2->pos = 0;
1577 			snprintf_num(U64, sb1, ctx->uvals[i]);
1578 			snprintf_num(S64, sb2, ctx->svals[i]);
1579 			printf("SEED #%d: u64=%-20s s64=%-20s\n", i, sb1->buf, sb2->buf);
1580 		}
1581 	}
1582 
1583 	/* 32-bit values are generated separately */
1584 	cnt = 0;
1585 	for (i = 0; i < ARRAY_SIZE(lower_seeds); i++) {
1586 		ctx->usubvals[cnt++] = lower_seeds[i];
1587 	}
1588 
1589 	/* sort and compact usubvals (i.e., it's `sort | uniq`) */
1590 	qsort(ctx->usubvals, cnt, sizeof(*ctx->usubvals), u32_cmp);
1591 	for (i = 1, j = 0; i < cnt; i++) {
1592 		if (ctx->usubvals[j] == ctx->usubvals[i])
1593 			continue;
1594 		j++;
1595 		ctx->usubvals[j] = ctx->usubvals[i];
1596 	}
1597 	ctx->subval_cnt = j + 1;
1598 
1599 	for (i = 0; i < ctx->subval_cnt; i++)
1600 		ctx->ssubvals[i] = ctx->usubvals[i];
1601 	qsort(ctx->ssubvals, ctx->subval_cnt, sizeof(*ctx->ssubvals), s32_cmp);
1602 
1603 	if (env.verbosity >= VERBOSE_SUPER) {
1604 		DEFINE_STRBUF(sb1, 256);
1605 		DEFINE_STRBUF(sb2, 256);
1606 
1607 		for (i = 0; i < ctx->subval_cnt; i++) {
1608 			sb1->pos = sb2->pos = 0;
1609 			snprintf_num(U32, sb1, ctx->usubvals[i]);
1610 			snprintf_num(S32, sb2, ctx->ssubvals[i]);
1611 			printf("SUBSEED #%d: u32=%-10s s32=%-10s\n", i, sb1->buf, sb2->buf);
1612 		}
1613 	}
1614 }
1615 
1616 /* Generate valid ranges from upper/lower seeds */
gen_ranges(struct ctx * ctx)1617 static int gen_ranges(struct ctx *ctx)
1618 {
1619 	int i, j, cnt = 0;
1620 
1621 	for (i = 0; i < ctx->val_cnt; i++) {
1622 		for (j = i; j < ctx->val_cnt; j++) {
1623 			if (env.verbosity >= VERBOSE_SUPER) {
1624 				DEFINE_STRBUF(sb1, 256);
1625 				DEFINE_STRBUF(sb2, 256);
1626 
1627 				sb1->pos = sb2->pos = 0;
1628 				snprintf_range(U64, sb1, range(U64, ctx->uvals[i], ctx->uvals[j]));
1629 				snprintf_range(S64, sb2, range(S64, ctx->svals[i], ctx->svals[j]));
1630 				printf("RANGE #%d: u64=%-40s s64=%-40s\n", cnt, sb1->buf, sb2->buf);
1631 			}
1632 			cnt++;
1633 		}
1634 	}
1635 	ctx->range_cnt = cnt;
1636 
1637 	ctx->uranges = calloc(ctx->range_cnt, sizeof(*ctx->uranges));
1638 	if (!ASSERT_OK_PTR(ctx->uranges, "uranges_calloc"))
1639 		return -EINVAL;
1640 	ctx->sranges = calloc(ctx->range_cnt, sizeof(*ctx->sranges));
1641 	if (!ASSERT_OK_PTR(ctx->sranges, "sranges_calloc"))
1642 		return -EINVAL;
1643 
1644 	cnt = 0;
1645 	for (i = 0; i < ctx->val_cnt; i++) {
1646 		for (j = i; j < ctx->val_cnt; j++) {
1647 			ctx->uranges[cnt] = range(U64, ctx->uvals[i], ctx->uvals[j]);
1648 			ctx->sranges[cnt] = range(S64, ctx->svals[i], ctx->svals[j]);
1649 			cnt++;
1650 		}
1651 	}
1652 
1653 	cnt = 0;
1654 	for (i = 0; i < ctx->subval_cnt; i++) {
1655 		for (j = i; j < ctx->subval_cnt; j++) {
1656 			if (env.verbosity >= VERBOSE_SUPER) {
1657 				DEFINE_STRBUF(sb1, 256);
1658 				DEFINE_STRBUF(sb2, 256);
1659 
1660 				sb1->pos = sb2->pos = 0;
1661 				snprintf_range(U32, sb1, range(U32, ctx->usubvals[i], ctx->usubvals[j]));
1662 				snprintf_range(S32, sb2, range(S32, ctx->ssubvals[i], ctx->ssubvals[j]));
1663 				printf("SUBRANGE #%d: u32=%-20s s32=%-20s\n", cnt, sb1->buf, sb2->buf);
1664 			}
1665 			cnt++;
1666 		}
1667 	}
1668 	ctx->subrange_cnt = cnt;
1669 
1670 	ctx->usubranges = calloc(ctx->subrange_cnt, sizeof(*ctx->usubranges));
1671 	if (!ASSERT_OK_PTR(ctx->usubranges, "usubranges_calloc"))
1672 		return -EINVAL;
1673 	ctx->ssubranges = calloc(ctx->subrange_cnt, sizeof(*ctx->ssubranges));
1674 	if (!ASSERT_OK_PTR(ctx->ssubranges, "ssubranges_calloc"))
1675 		return -EINVAL;
1676 
1677 	cnt = 0;
1678 	for (i = 0; i < ctx->subval_cnt; i++) {
1679 		for (j = i; j < ctx->subval_cnt; j++) {
1680 			ctx->usubranges[cnt] = range(U32, ctx->usubvals[i], ctx->usubvals[j]);
1681 			ctx->ssubranges[cnt] = range(S32, ctx->ssubvals[i], ctx->ssubvals[j]);
1682 			cnt++;
1683 		}
1684 	}
1685 
1686 	return 0;
1687 }
1688 
parse_env_vars(struct ctx * ctx)1689 static int parse_env_vars(struct ctx *ctx)
1690 {
1691 	const char *s;
1692 
1693 	if ((s = getenv("REG_BOUNDS_MAX_FAILURE_CNT"))) {
1694 		errno = 0;
1695 		ctx->max_failure_cnt = strtol(s, NULL, 10);
1696 		if (errno || ctx->max_failure_cnt < 0) {
1697 			ASSERT_OK(-errno, "REG_BOUNDS_MAX_FAILURE_CNT");
1698 			return -EINVAL;
1699 		}
1700 	}
1701 
1702 	if ((s = getenv("REG_BOUNDS_RAND_CASE_CNT"))) {
1703 		errno = 0;
1704 		ctx->rand_case_cnt = strtol(s, NULL, 10);
1705 		if (errno || ctx->rand_case_cnt < 0) {
1706 			ASSERT_OK(-errno, "REG_BOUNDS_RAND_CASE_CNT");
1707 			return -EINVAL;
1708 		}
1709 	}
1710 
1711 	if ((s = getenv("REG_BOUNDS_RAND_SEED"))) {
1712 		errno = 0;
1713 		ctx->rand_seed = strtoul(s, NULL, 10);
1714 		if (errno) {
1715 			ASSERT_OK(-errno, "REG_BOUNDS_RAND_SEED");
1716 			return -EINVAL;
1717 		}
1718 	}
1719 
1720 	return 0;
1721 }
1722 
prepare_gen_tests(struct ctx * ctx)1723 static int prepare_gen_tests(struct ctx *ctx)
1724 {
1725 	const char *s;
1726 	int err;
1727 
1728 	if (!(s = getenv("SLOW_TESTS")) || strcmp(s, "1") != 0) {
1729 		test__skip();
1730 		return -ENOTSUP;
1731 	}
1732 
1733 	err = parse_env_vars(ctx);
1734 	if (err)
1735 		return err;
1736 
1737 	gen_vals(ctx);
1738 	err = gen_ranges(ctx);
1739 	if (err) {
1740 		ASSERT_OK(err, "gen_ranges");
1741 		return err;
1742 	}
1743 
1744 	return 0;
1745 }
1746 
1747 /* Go over generated constants and ranges and validate various supported
1748  * combinations of them
1749  */
validate_gen_range_vs_const_64(enum num_t init_t,enum num_t cond_t)1750 static void validate_gen_range_vs_const_64(enum num_t init_t, enum num_t cond_t)
1751 {
1752 	struct ctx ctx;
1753 	struct range rconst;
1754 	const struct range *ranges;
1755 	const u64 *vals;
1756 	int i, j;
1757 
1758 	memset(&ctx, 0, sizeof(ctx));
1759 
1760 	if (prepare_gen_tests(&ctx))
1761 		goto cleanup;
1762 
1763 	ranges = init_t == U64 ? ctx.uranges : ctx.sranges;
1764 	vals = init_t == U64 ? ctx.uvals : (const u64 *)ctx.svals;
1765 
1766 	ctx.total_case_cnt = (last_op - first_op + 1) * (2 * ctx.range_cnt * ctx.val_cnt);
1767 	ctx.start_ns = get_time_ns();
1768 	snprintf(ctx.progress_ctx, sizeof(ctx.progress_ctx),
1769 		 "RANGE x CONST, %s -> %s",
1770 		 t_str(init_t), t_str(cond_t));
1771 
1772 	for (i = 0; i < ctx.val_cnt; i++) {
1773 		for (j = 0; j < ctx.range_cnt; j++) {
1774 			rconst = range(init_t, vals[i], vals[i]);
1775 
1776 			/* (u64|s64)(<range> x <const>) */
1777 			if (verify_case(&ctx, init_t, cond_t, ranges[j], rconst))
1778 				goto cleanup;
1779 			/* (u64|s64)(<const> x <range>) */
1780 			if (verify_case(&ctx, init_t, cond_t, rconst, ranges[j]))
1781 				goto cleanup;
1782 		}
1783 	}
1784 
1785 cleanup:
1786 	cleanup_ctx(&ctx);
1787 }
1788 
validate_gen_range_vs_const_32(enum num_t init_t,enum num_t cond_t)1789 static void validate_gen_range_vs_const_32(enum num_t init_t, enum num_t cond_t)
1790 {
1791 	struct ctx ctx;
1792 	struct range rconst;
1793 	const struct range *ranges;
1794 	const u32 *vals;
1795 	int i, j;
1796 
1797 	memset(&ctx, 0, sizeof(ctx));
1798 
1799 	if (prepare_gen_tests(&ctx))
1800 		goto cleanup;
1801 
1802 	ranges = init_t == U32 ? ctx.usubranges : ctx.ssubranges;
1803 	vals = init_t == U32 ? ctx.usubvals : (const u32 *)ctx.ssubvals;
1804 
1805 	ctx.total_case_cnt = (last_op - first_op + 1) * (2 * ctx.subrange_cnt * ctx.subval_cnt);
1806 	ctx.start_ns = get_time_ns();
1807 	snprintf(ctx.progress_ctx, sizeof(ctx.progress_ctx),
1808 		 "RANGE x CONST, %s -> %s",
1809 		 t_str(init_t), t_str(cond_t));
1810 
1811 	for (i = 0; i < ctx.subval_cnt; i++) {
1812 		for (j = 0; j < ctx.subrange_cnt; j++) {
1813 			rconst = range(init_t, vals[i], vals[i]);
1814 
1815 			/* (u32|s32)(<range> x <const>) */
1816 			if (verify_case(&ctx, init_t, cond_t, ranges[j], rconst))
1817 				goto cleanup;
1818 			/* (u32|s32)(<const> x <range>) */
1819 			if (verify_case(&ctx, init_t, cond_t, rconst, ranges[j]))
1820 				goto cleanup;
1821 		}
1822 	}
1823 
1824 cleanup:
1825 	cleanup_ctx(&ctx);
1826 }
1827 
validate_gen_range_vs_range(enum num_t init_t,enum num_t cond_t)1828 static void validate_gen_range_vs_range(enum num_t init_t, enum num_t cond_t)
1829 {
1830 	struct ctx ctx;
1831 	const struct range *ranges;
1832 	int i, j, rcnt;
1833 
1834 	memset(&ctx, 0, sizeof(ctx));
1835 
1836 	if (prepare_gen_tests(&ctx))
1837 		goto cleanup;
1838 
1839 	switch (init_t)
1840 	{
1841 	case U64:
1842 		ranges = ctx.uranges;
1843 		rcnt = ctx.range_cnt;
1844 		break;
1845 	case U32:
1846 		ranges = ctx.usubranges;
1847 		rcnt = ctx.subrange_cnt;
1848 		break;
1849 	case S64:
1850 		ranges = ctx.sranges;
1851 		rcnt = ctx.range_cnt;
1852 		break;
1853 	case S32:
1854 		ranges = ctx.ssubranges;
1855 		rcnt = ctx.subrange_cnt;
1856 		break;
1857 	default:
1858 		printf("validate_gen_range_vs_range!\n");
1859 		exit(1);
1860 	}
1861 
1862 	ctx.total_case_cnt = (last_op - first_op + 1) * (2 * rcnt * (rcnt + 1) / 2);
1863 	ctx.start_ns = get_time_ns();
1864 	snprintf(ctx.progress_ctx, sizeof(ctx.progress_ctx),
1865 		 "RANGE x RANGE, %s -> %s",
1866 		 t_str(init_t), t_str(cond_t));
1867 
1868 	for (i = 0; i < rcnt; i++) {
1869 		for (j = i; j < rcnt; j++) {
1870 			/* (<range> x <range>) */
1871 			if (verify_case(&ctx, init_t, cond_t, ranges[i], ranges[j]))
1872 				goto cleanup;
1873 			if (verify_case(&ctx, init_t, cond_t, ranges[j], ranges[i]))
1874 				goto cleanup;
1875 		}
1876 	}
1877 
1878 cleanup:
1879 	cleanup_ctx(&ctx);
1880 }
1881 
1882 /* Go over thousands of test cases generated from initial seed values.
1883  * Given this take a long time, guard this begind SLOW_TESTS=1 envvar. If
1884  * envvar is not set, this test is skipped during test_progs testing.
1885  *
1886  * We split this up into smaller subsets based on initialization and
1887  * conditional numeric domains to get an easy parallelization with test_progs'
1888  * -j argument.
1889  */
1890 
1891 /* RANGE x CONST, U64 initial range */
test_reg_bounds_gen_consts_u64_u64(void)1892 void test_reg_bounds_gen_consts_u64_u64(void) { validate_gen_range_vs_const_64(U64, U64); }
test_reg_bounds_gen_consts_u64_s64(void)1893 void test_reg_bounds_gen_consts_u64_s64(void) { validate_gen_range_vs_const_64(U64, S64); }
test_reg_bounds_gen_consts_u64_u32(void)1894 void test_reg_bounds_gen_consts_u64_u32(void) { validate_gen_range_vs_const_64(U64, U32); }
test_reg_bounds_gen_consts_u64_s32(void)1895 void test_reg_bounds_gen_consts_u64_s32(void) { validate_gen_range_vs_const_64(U64, S32); }
1896 /* RANGE x CONST, S64 initial range */
test_reg_bounds_gen_consts_s64_u64(void)1897 void test_reg_bounds_gen_consts_s64_u64(void) { validate_gen_range_vs_const_64(S64, U64); }
test_reg_bounds_gen_consts_s64_s64(void)1898 void test_reg_bounds_gen_consts_s64_s64(void) { validate_gen_range_vs_const_64(S64, S64); }
test_reg_bounds_gen_consts_s64_u32(void)1899 void test_reg_bounds_gen_consts_s64_u32(void) { validate_gen_range_vs_const_64(S64, U32); }
test_reg_bounds_gen_consts_s64_s32(void)1900 void test_reg_bounds_gen_consts_s64_s32(void) { validate_gen_range_vs_const_64(S64, S32); }
1901 /* RANGE x CONST, U32 initial range */
test_reg_bounds_gen_consts_u32_u64(void)1902 void test_reg_bounds_gen_consts_u32_u64(void) { validate_gen_range_vs_const_32(U32, U64); }
test_reg_bounds_gen_consts_u32_s64(void)1903 void test_reg_bounds_gen_consts_u32_s64(void) { validate_gen_range_vs_const_32(U32, S64); }
test_reg_bounds_gen_consts_u32_u32(void)1904 void test_reg_bounds_gen_consts_u32_u32(void) { validate_gen_range_vs_const_32(U32, U32); }
test_reg_bounds_gen_consts_u32_s32(void)1905 void test_reg_bounds_gen_consts_u32_s32(void) { validate_gen_range_vs_const_32(U32, S32); }
1906 /* RANGE x CONST, S32 initial range */
test_reg_bounds_gen_consts_s32_u64(void)1907 void test_reg_bounds_gen_consts_s32_u64(void) { validate_gen_range_vs_const_32(S32, U64); }
test_reg_bounds_gen_consts_s32_s64(void)1908 void test_reg_bounds_gen_consts_s32_s64(void) { validate_gen_range_vs_const_32(S32, S64); }
test_reg_bounds_gen_consts_s32_u32(void)1909 void test_reg_bounds_gen_consts_s32_u32(void) { validate_gen_range_vs_const_32(S32, U32); }
test_reg_bounds_gen_consts_s32_s32(void)1910 void test_reg_bounds_gen_consts_s32_s32(void) { validate_gen_range_vs_const_32(S32, S32); }
1911 
1912 /* RANGE x RANGE, U64 initial range */
test_reg_bounds_gen_ranges_u64_u64(void)1913 void test_reg_bounds_gen_ranges_u64_u64(void) { validate_gen_range_vs_range(U64, U64); }
test_reg_bounds_gen_ranges_u64_s64(void)1914 void test_reg_bounds_gen_ranges_u64_s64(void) { validate_gen_range_vs_range(U64, S64); }
test_reg_bounds_gen_ranges_u64_u32(void)1915 void test_reg_bounds_gen_ranges_u64_u32(void) { validate_gen_range_vs_range(U64, U32); }
test_reg_bounds_gen_ranges_u64_s32(void)1916 void test_reg_bounds_gen_ranges_u64_s32(void) { validate_gen_range_vs_range(U64, S32); }
1917 /* RANGE x RANGE, S64 initial range */
test_reg_bounds_gen_ranges_s64_u64(void)1918 void test_reg_bounds_gen_ranges_s64_u64(void) { validate_gen_range_vs_range(S64, U64); }
test_reg_bounds_gen_ranges_s64_s64(void)1919 void test_reg_bounds_gen_ranges_s64_s64(void) { validate_gen_range_vs_range(S64, S64); }
test_reg_bounds_gen_ranges_s64_u32(void)1920 void test_reg_bounds_gen_ranges_s64_u32(void) { validate_gen_range_vs_range(S64, U32); }
test_reg_bounds_gen_ranges_s64_s32(void)1921 void test_reg_bounds_gen_ranges_s64_s32(void) { validate_gen_range_vs_range(S64, S32); }
1922 /* RANGE x RANGE, U32 initial range */
test_reg_bounds_gen_ranges_u32_u64(void)1923 void test_reg_bounds_gen_ranges_u32_u64(void) { validate_gen_range_vs_range(U32, U64); }
test_reg_bounds_gen_ranges_u32_s64(void)1924 void test_reg_bounds_gen_ranges_u32_s64(void) { validate_gen_range_vs_range(U32, S64); }
test_reg_bounds_gen_ranges_u32_u32(void)1925 void test_reg_bounds_gen_ranges_u32_u32(void) { validate_gen_range_vs_range(U32, U32); }
test_reg_bounds_gen_ranges_u32_s32(void)1926 void test_reg_bounds_gen_ranges_u32_s32(void) { validate_gen_range_vs_range(U32, S32); }
1927 /* RANGE x RANGE, S32 initial range */
test_reg_bounds_gen_ranges_s32_u64(void)1928 void test_reg_bounds_gen_ranges_s32_u64(void) { validate_gen_range_vs_range(S32, U64); }
test_reg_bounds_gen_ranges_s32_s64(void)1929 void test_reg_bounds_gen_ranges_s32_s64(void) { validate_gen_range_vs_range(S32, S64); }
test_reg_bounds_gen_ranges_s32_u32(void)1930 void test_reg_bounds_gen_ranges_s32_u32(void) { validate_gen_range_vs_range(S32, U32); }
test_reg_bounds_gen_ranges_s32_s32(void)1931 void test_reg_bounds_gen_ranges_s32_s32(void) { validate_gen_range_vs_range(S32, S32); }
1932 
1933 #define DEFAULT_RAND_CASE_CNT 100
1934 
1935 #define RAND_21BIT_MASK ((1 << 22) - 1)
1936 
rand_u64()1937 static u64 rand_u64()
1938 {
1939 	/* RAND_MAX is guaranteed to be at least 1<<15, but in practice it
1940 	 * seems to be 1<<31, so we need to call it thrice to get full u64;
1941 	 * we'll use roughly equal split: 22 + 21 + 21 bits
1942 	 */
1943 	return ((u64)random() << 42) |
1944 	       (((u64)random() & RAND_21BIT_MASK) << 21) |
1945 	       (random() & RAND_21BIT_MASK);
1946 }
1947 
rand_const(enum num_t t)1948 static u64 rand_const(enum num_t t)
1949 {
1950 	return cast_t(t, rand_u64());
1951 }
1952 
rand_range(enum num_t t)1953 static struct range rand_range(enum num_t t)
1954 {
1955 	u64 x = rand_const(t), y = rand_const(t);
1956 
1957 	return range(t, min_t(t, x, y), max_t(t, x, y));
1958 }
1959 
validate_rand_ranges(enum num_t init_t,enum num_t cond_t,bool const_range)1960 static void validate_rand_ranges(enum num_t init_t, enum num_t cond_t, bool const_range)
1961 {
1962 	struct ctx ctx;
1963 	struct range range1, range2;
1964 	int err, i;
1965 	u64 t;
1966 
1967 	memset(&ctx, 0, sizeof(ctx));
1968 
1969 	err = parse_env_vars(&ctx);
1970 	if (err) {
1971 		ASSERT_OK(err, "parse_env_vars");
1972 		return;
1973 	}
1974 
1975 	if (ctx.rand_case_cnt == 0)
1976 		ctx.rand_case_cnt = DEFAULT_RAND_CASE_CNT;
1977 	if (ctx.rand_seed == 0)
1978 		ctx.rand_seed = (unsigned)get_time_ns();
1979 
1980 	srandom(ctx.rand_seed);
1981 
1982 	ctx.total_case_cnt = (last_op - first_op + 1) * (2 * ctx.rand_case_cnt);
1983 	ctx.start_ns = get_time_ns();
1984 	snprintf(ctx.progress_ctx, sizeof(ctx.progress_ctx),
1985 		 "[RANDOM SEED %u] RANGE x %s, %s -> %s",
1986 		 ctx.rand_seed, const_range ? "CONST" : "RANGE",
1987 		 t_str(init_t), t_str(cond_t));
1988 
1989 	for (i = 0; i < ctx.rand_case_cnt; i++) {
1990 		range1 = rand_range(init_t);
1991 		if (const_range) {
1992 			t = rand_const(init_t);
1993 			range2 = range(init_t, t, t);
1994 		} else {
1995 			range2 = rand_range(init_t);
1996 		}
1997 
1998 		/* <range1> x <range2> */
1999 		if (verify_case_opt(&ctx, init_t, cond_t, range1, range2, false /* !is_subtest */))
2000 			goto cleanup;
2001 		/* <range2> x <range1> */
2002 		if (verify_case_opt(&ctx, init_t, cond_t, range2, range1, false /* !is_subtest */))
2003 			goto cleanup;
2004 	}
2005 
2006 cleanup:
2007 	/* make sure we report random seed for reproducing */
2008 	ASSERT_TRUE(true, ctx.progress_ctx);
2009 	cleanup_ctx(&ctx);
2010 }
2011 
2012 /* [RANDOM] RANGE x CONST, U64 initial range */
test_reg_bounds_rand_consts_u64_u64(void)2013 void test_reg_bounds_rand_consts_u64_u64(void) { validate_rand_ranges(U64, U64, true /* const */); }
test_reg_bounds_rand_consts_u64_s64(void)2014 void test_reg_bounds_rand_consts_u64_s64(void) { validate_rand_ranges(U64, S64, true /* const */); }
test_reg_bounds_rand_consts_u64_u32(void)2015 void test_reg_bounds_rand_consts_u64_u32(void) { validate_rand_ranges(U64, U32, true /* const */); }
test_reg_bounds_rand_consts_u64_s32(void)2016 void test_reg_bounds_rand_consts_u64_s32(void) { validate_rand_ranges(U64, S32, true /* const */); }
2017 /* [RANDOM] RANGE x CONST, S64 initial range */
test_reg_bounds_rand_consts_s64_u64(void)2018 void test_reg_bounds_rand_consts_s64_u64(void) { validate_rand_ranges(S64, U64, true /* const */); }
test_reg_bounds_rand_consts_s64_s64(void)2019 void test_reg_bounds_rand_consts_s64_s64(void) { validate_rand_ranges(S64, S64, true /* const */); }
test_reg_bounds_rand_consts_s64_u32(void)2020 void test_reg_bounds_rand_consts_s64_u32(void) { validate_rand_ranges(S64, U32, true /* const */); }
test_reg_bounds_rand_consts_s64_s32(void)2021 void test_reg_bounds_rand_consts_s64_s32(void) { validate_rand_ranges(S64, S32, true /* const */); }
2022 /* [RANDOM] RANGE x CONST, U32 initial range */
test_reg_bounds_rand_consts_u32_u64(void)2023 void test_reg_bounds_rand_consts_u32_u64(void) { validate_rand_ranges(U32, U64, true /* const */); }
test_reg_bounds_rand_consts_u32_s64(void)2024 void test_reg_bounds_rand_consts_u32_s64(void) { validate_rand_ranges(U32, S64, true /* const */); }
test_reg_bounds_rand_consts_u32_u32(void)2025 void test_reg_bounds_rand_consts_u32_u32(void) { validate_rand_ranges(U32, U32, true /* const */); }
test_reg_bounds_rand_consts_u32_s32(void)2026 void test_reg_bounds_rand_consts_u32_s32(void) { validate_rand_ranges(U32, S32, true /* const */); }
2027 /* [RANDOM] RANGE x CONST, S32 initial range */
test_reg_bounds_rand_consts_s32_u64(void)2028 void test_reg_bounds_rand_consts_s32_u64(void) { validate_rand_ranges(S32, U64, true /* const */); }
test_reg_bounds_rand_consts_s32_s64(void)2029 void test_reg_bounds_rand_consts_s32_s64(void) { validate_rand_ranges(S32, S64, true /* const */); }
test_reg_bounds_rand_consts_s32_u32(void)2030 void test_reg_bounds_rand_consts_s32_u32(void) { validate_rand_ranges(S32, U32, true /* const */); }
test_reg_bounds_rand_consts_s32_s32(void)2031 void test_reg_bounds_rand_consts_s32_s32(void) { validate_rand_ranges(S32, S32, true /* const */); }
2032 
2033 /* [RANDOM] RANGE x RANGE, U64 initial range */
test_reg_bounds_rand_ranges_u64_u64(void)2034 void test_reg_bounds_rand_ranges_u64_u64(void) { validate_rand_ranges(U64, U64, false /* range */); }
test_reg_bounds_rand_ranges_u64_s64(void)2035 void test_reg_bounds_rand_ranges_u64_s64(void) { validate_rand_ranges(U64, S64, false /* range */); }
test_reg_bounds_rand_ranges_u64_u32(void)2036 void test_reg_bounds_rand_ranges_u64_u32(void) { validate_rand_ranges(U64, U32, false /* range */); }
test_reg_bounds_rand_ranges_u64_s32(void)2037 void test_reg_bounds_rand_ranges_u64_s32(void) { validate_rand_ranges(U64, S32, false /* range */); }
2038 /* [RANDOM] RANGE x RANGE, S64 initial range */
test_reg_bounds_rand_ranges_s64_u64(void)2039 void test_reg_bounds_rand_ranges_s64_u64(void) { validate_rand_ranges(S64, U64, false /* range */); }
test_reg_bounds_rand_ranges_s64_s64(void)2040 void test_reg_bounds_rand_ranges_s64_s64(void) { validate_rand_ranges(S64, S64, false /* range */); }
test_reg_bounds_rand_ranges_s64_u32(void)2041 void test_reg_bounds_rand_ranges_s64_u32(void) { validate_rand_ranges(S64, U32, false /* range */); }
test_reg_bounds_rand_ranges_s64_s32(void)2042 void test_reg_bounds_rand_ranges_s64_s32(void) { validate_rand_ranges(S64, S32, false /* range */); }
2043 /* [RANDOM] RANGE x RANGE, U32 initial range */
test_reg_bounds_rand_ranges_u32_u64(void)2044 void test_reg_bounds_rand_ranges_u32_u64(void) { validate_rand_ranges(U32, U64, false /* range */); }
test_reg_bounds_rand_ranges_u32_s64(void)2045 void test_reg_bounds_rand_ranges_u32_s64(void) { validate_rand_ranges(U32, S64, false /* range */); }
test_reg_bounds_rand_ranges_u32_u32(void)2046 void test_reg_bounds_rand_ranges_u32_u32(void) { validate_rand_ranges(U32, U32, false /* range */); }
test_reg_bounds_rand_ranges_u32_s32(void)2047 void test_reg_bounds_rand_ranges_u32_s32(void) { validate_rand_ranges(U32, S32, false /* range */); }
2048 /* [RANDOM] RANGE x RANGE, S32 initial range */
test_reg_bounds_rand_ranges_s32_u64(void)2049 void test_reg_bounds_rand_ranges_s32_u64(void) { validate_rand_ranges(S32, U64, false /* range */); }
test_reg_bounds_rand_ranges_s32_s64(void)2050 void test_reg_bounds_rand_ranges_s32_s64(void) { validate_rand_ranges(S32, S64, false /* range */); }
test_reg_bounds_rand_ranges_s32_u32(void)2051 void test_reg_bounds_rand_ranges_s32_u32(void) { validate_rand_ranges(S32, U32, false /* range */); }
test_reg_bounds_rand_ranges_s32_s32(void)2052 void test_reg_bounds_rand_ranges_s32_s32(void) { validate_rand_ranges(S32, S32, false /* range */); }
2053 
2054 /* A set of hard-coded "interesting" cases to validate as part of normal
2055  * test_progs test runs
2056  */
2057 static struct subtest_case crafted_cases[] = {
2058 	{U64, U64, {0, 0xffffffff}, {0, 0}},
2059 	{U64, U64, {0, 0x80000000}, {0, 0}},
2060 	{U64, U64, {0x100000000ULL, 0x100000100ULL}, {0, 0}},
2061 	{U64, U64, {0x100000000ULL, 0x180000000ULL}, {0, 0}},
2062 	{U64, U64, {0x100000000ULL, 0x1ffffff00ULL}, {0, 0}},
2063 	{U64, U64, {0x100000000ULL, 0x1ffffff01ULL}, {0, 0}},
2064 	{U64, U64, {0x100000000ULL, 0x1fffffffeULL}, {0, 0}},
2065 	{U64, U64, {0x100000001ULL, 0x1000000ffULL}, {0, 0}},
2066 
2067 	/* single point overlap, interesting BPF_EQ and BPF_NE interactions */
2068 	{U64, U64, {0, 1}, {1, 0x80000000}},
2069 	{U64, S64, {0, 1}, {1, 0x80000000}},
2070 	{U64, U32, {0, 1}, {1, 0x80000000}},
2071 	{U64, S32, {0, 1}, {1, 0x80000000}},
2072 
2073 	{U64, S64, {0, 0xffffffff00000000ULL}, {0, 0}},
2074 	{U64, S64, {0x7fffffffffffffffULL, 0xffffffff00000000ULL}, {0, 0}},
2075 	{U64, S64, {0x7fffffff00000001ULL, 0xffffffff00000000ULL}, {0, 0}},
2076 	{U64, S64, {0, 0xffffffffULL}, {1, 1}},
2077 	{U64, S64, {0, 0xffffffffULL}, {0x7fffffff, 0x7fffffff}},
2078 
2079 	{U64, U32, {0, 0x100000000}, {0, 0}},
2080 	{U64, U32, {0xfffffffe, 0x100000000}, {0x80000000, 0x80000000}},
2081 
2082 	{U64, S32, {0, 0xffffffff00000000ULL}, {0, 0}},
2083 	/* these are tricky cases where lower 32 bits allow to tighten 64
2084 	 * bit boundaries based on tightened lower 32 bit boundaries
2085 	 */
2086 	{U64, S32, {0, 0x0ffffffffULL}, {0, 0}},
2087 	{U64, S32, {0, 0x100000000ULL}, {0, 0}},
2088 	{U64, S32, {0, 0x100000001ULL}, {0, 0}},
2089 	{U64, S32, {0, 0x180000000ULL}, {0, 0}},
2090 	{U64, S32, {0, 0x17fffffffULL}, {0, 0}},
2091 	{U64, S32, {0, 0x180000001ULL}, {0, 0}},
2092 
2093 	/* verifier knows about [-1, 0] range for s32 for this case already */
2094 	{S64, S64, {0xffffffffffffffffULL, 0}, {0xffffffff00000000ULL, 0xffffffff00000000ULL}},
2095 	/* but didn't know about these cases initially */
2096 	{U64, U64, {0xffffffff, 0x100000000ULL}, {0, 0}}, /* s32: [-1, 0] */
2097 	{U64, U64, {0xffffffff, 0x100000001ULL}, {0, 0}}, /* s32: [-1, 1] */
2098 
2099 	/* longer convergence case: learning from u64 -> s64 -> u64 -> u32,
2100 	 * arriving at u32: [1, U32_MAX] (instead of more pessimistic [0, U32_MAX])
2101 	 */
2102 	{S64, U64, {0xffffffff00000001ULL, 0}, {0xffffffff00000000ULL, 0xffffffff00000000ULL}},
2103 
2104 	{U32, U32, {1, U32_MAX}, {0, 0}},
2105 
2106 	{U32, S32, {0, U32_MAX}, {U32_MAX, U32_MAX}},
2107 
2108 	{S32, U64, {(u32)S32_MIN, (u32)S32_MIN}, {(u32)(s32)-255, 0}},
2109 	{S32, S64, {(u32)S32_MIN, (u32)(s32)-255}, {(u32)(s32)-2, 0}},
2110 	{S32, S64, {0, 1}, {(u32)S32_MIN, (u32)S32_MIN}},
2111 	{S32, U32, {(u32)S32_MIN, (u32)S32_MIN}, {(u32)S32_MIN, (u32)S32_MIN}},
2112 
2113 	/* edge overlap testings for BPF_NE */
2114 	{U64, U64, {0, U64_MAX}, {U64_MAX, U64_MAX}},
2115 	{U64, U64, {0, U64_MAX}, {0, 0}},
2116 	{S64, U64, {S64_MIN, 0}, {S64_MIN, S64_MIN}},
2117 	{S64, U64, {S64_MIN, 0}, {0, 0}},
2118 	{S64, U64, {S64_MIN, S64_MAX}, {S64_MAX, S64_MAX}},
2119 	{U32, U32, {0, U32_MAX}, {0, 0}},
2120 	{U32, U32, {0, U32_MAX}, {U32_MAX, U32_MAX}},
2121 	{S32, U32, {(u32)S32_MIN, 0}, {0, 0}},
2122 	{S32, U32, {(u32)S32_MIN, 0}, {(u32)S32_MIN, (u32)S32_MIN}},
2123 	{S32, U32, {(u32)S32_MIN, S32_MAX}, {S32_MAX, S32_MAX}},
2124 	{S64, U32, {0x0, 0x1f}, {0xffffffff80000000ULL, 0x000000007fffffffULL}},
2125 	{S64, U32, {0x0, 0x1f}, {0xffffffffffff8000ULL, 0x0000000000007fffULL}},
2126 	{S64, U32, {0x0, 0x1f}, {0xffffffffffffff80ULL, 0x000000000000007fULL}},
2127 };
2128 
2129 /* Go over crafted hard-coded cases. This is fast, so we do it as part of
2130  * normal test_progs run.
2131  */
test_reg_bounds_crafted(void)2132 void test_reg_bounds_crafted(void)
2133 {
2134 	struct ctx ctx;
2135 	int i;
2136 
2137 	memset(&ctx, 0, sizeof(ctx));
2138 
2139 	for (i = 0; i < ARRAY_SIZE(crafted_cases); i++) {
2140 		struct subtest_case *c = &crafted_cases[i];
2141 
2142 		verify_case(&ctx, c->init_t, c->cond_t, c->x, c->y);
2143 		verify_case(&ctx, c->init_t, c->cond_t, c->y, c->x);
2144 	}
2145 
2146 	cleanup_ctx(&ctx);
2147 }
2148